CONTENTS · By : Ir. Prof. Abang Abdullah bin Abang Ali, IEM President PRESIDENT’S CORNER CALL FOR CONTRIBUTIONS To all Members and Readers, The Editorial Board is planning for

JURUTERA, February 2005 3

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PRESIDENT’S CORNERThe Young Renaissance: Time To Let Go? ............................................. 4

COVER STORYLRT Launchers Did The Trick For Bridge Superstructure Over Jalan Kuching! .................................................................................. 6

FEATURESHot In-Place Recycling : An Introduction .............................................. 10“How Much Settlement Do You Allow For In Your Buildings?” ........................................................................................ 20Renewable Energy – The Need For Further Incentives ....................... 26Scaling Greater Heights After Retirement .............................................. 35

COMMENTThe Engineer’s Dilemma .......................................................................... 32

LETTER TO EDITOR .......................................................... 16

BLUE PAGESMembership ............................................................................................... 1ANNOUNCEMENTIEM Diary/Conference & Seminar ........................................................ 3Engineering Week 2005 ............................................................................ 3

REPORTReport On CETD Postgraduate Students Essay Competition ................................................................................................ 2One Day Seminar on “Acoustics & Noise Control In Buildings” ............................................................................................... 4The Seismic Refraction Technique In Engineering Applications ......................................................................... 5Talk On “Fundamentals And Application Of Adsorption Processes” .............................................................................. 6IEM Site Visit To Sistem Lingkaran Lebuhraya Kajang Sdn Bhd (SILK) ............................................................................. 6Talk On “Mechanical System Design For Large Shopping Mall” ............................................................................... 7New Books In The Library ....................................................................... 8

Brooklyn Bridge in New York City,opened in 1883. It took 14 years to

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also crowned the longestsuspension bridge in the world.

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JURUTERA, February 20054

The Institution of Civil Engineers(ICE), U.K. recently announced

the appointment of the youngestpresident, Colin Clinton, to take overthe 187 year old institution which hassome 70 000 members worldwide,including a good number in Malaysia.His predecessor on a tour of this region last year brought along arepresentative of the young engineersin addition to his Director ofKnowledge. During the last WFEOGeneral Assembly and WorldEngineering Convention in Shanghaiin November, a protem committee for aYoung Engineers Group was formedand in the recent CAFEO22 inMyanmar in December, the YoungEngineers literally stole the show,coming in full force and providingmuch enthusiasm and support to thegathering of some 1000 engineers in Yangon.

It appears the days of the youngengineers have finally arrived. Downin Malaysia, graduate engineersconstitute 75% of the total registeredengineers with the Board of Engineers,Malaysia. And in IEM, the Graduate &Student Section (G&S) is definitely onthe upswing, being one of the mostactive sections in the IEM andundertaking a number of new andinteresting initiatives and projects. Our IEM G&S is represented in theWFEO Young Engineers protemcommittee and were actively involvedin CAFEO22.

All these developments can onlybring a good omen to the engineeringprofession which is currently sufferingfrom loss of respect especially amongstschool leaving children compared withmany other professions. The muchneeded injection of young blood hasfinally come, to ensure the profession

as well as the institution are againimbued with the dynamism andcreativity that is so important to amodern organisation. It is easy to becomplacent, enjoying our comfort zoneand becoming oblivious of the fact thatthe world is moving on. Too manyorganisations had suffered from theold-men’s club syndrome wherecreativity and innovations are sent tothe back burners. Under a goodleadership, the young engineers canhave a better chance of returningengineering to its former glory.

A good leader is one who knowsthe time to let go gracefully andwithout leaving a bomb in his chair. Isincerely believe it is time to supportand slowly make way for theemergence of the younger generationwhile we remain ever ready to offerany advice or assistance that they mayneed in their endeavour. n

The Young Renaissance: Time To Let Go?...................................................................................................................................................................................

By : Ir. Prof. Abang Abdullah bin Abang Ali, IEM President

P R E S I D E N T ’ S C O R N E R

CALL FOR CONTRIBUTIONS

To all Members and Readers, The Editorial Board is planning for future issues of the Bulletin. Those interested in contributing

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Please submit contributions early tomeet our material deadline.

Apr 2005 Geotechnical Engineering

May 2005 Mobile Services & Devices

Jun 2005 Agriculture Engineering

Jul 2005 Computer Engineering

Aug 2005 Leading – Edge Technologies

Sep 2005 Disaster Management

MONTH THEME


Specialists and Early SpecialisationBy: Ir. Hj. Look Keman bin Sahari

Number 2 February 2005IEM Registered on 1st May 1959

Iwas a council member representing Chemical and Othersfrom the 1997-2000 session. Being a member of a smaller

discipline, I can see the problems facing members fromthese smaller specialised disciplines. We are not only welldistributed throughout the country thus making it difficultto congregate together to attend a meeting, it is alsodifficult to get a quorum for an AGM or even normalmeetings. We face the problems of being small and more orless specialised. A geological engineer for example can beconsidered as a subset of a civil engineer and has tocompete with them, but cannot practice as a civil engineer.

An explosive engineer like me has to compete withmining engineers, civil engineers and even mechanicalengineers to prepare explosives and blasting reports. Onegovernment department may accept a professional reportand plan from an engineer of a related discipline only butanother may accept a report from any engineer as long asthe engineer has a P.E. and the experience. This sometimesmake us wonder whether it is worthwhile to go for aspecialised degree early and find that the demand for suchengineers is very limited; or it may be better to go for acommon engineering first degree and a specialised degreelater. There are pros and cons on this subject and there is anever-ending debate on it.

The other subject of interest is: doctors who havepostgraduate degrees and training call themselvesspecialists or “doktor pakar” after a certain number of yearsof training. I don’t understand why engineers with severaldegrees and fellowships dare not call themselvesspecialists while many expatriates who come to Malaysiato work do call themselves as such. Are we so humble orwe dare not take responsibility of being called “expert”? Itis a high time that we should consider this particular route.It will help differentiate between the real expert and a jack-of-all-trade engineer who can do a little bit of everythingbut is a master of nothing. I know there are many engineerswho are experts in many fields but if they don’t declarethemselves as such how would a potential client knowwho should he go for consultation. This could also be areason why many local contractors go for foreignengineering consultants. I think we should be braveenough to tell others that we are an expert in our particularfield. Then we can go and compete with others as expertslocally and also overseas. Maybe we should set a rule onwhen we can call ourselves expert (jurutera pakar).

How about those who go for early specialisation suchas geological engineers, aeronautic engineers, andpetroleum mining and mineral engineers. Can we callthem expert after a certain qualifying training andexperience? After all, the job market for early specialisationis so limited.

I hope this will be food for thought to those engineersfrom specialised disciplines like mine and also others whoare really specialists. n

THE INSTITUTION OF ENGINEERS, MALAYSIABangunan Ingenieur, Lots 60 & 62, Jalan 52/4, P.O. Box 223,

(Jalan Sultan) 46720 Petaling Jaya, Selangor.Tel: 03-7968 4001/4002 Fax: 03-7957 7678

E-mail: [email protected] Homepage: http://www.iem.org.my

MAJLIS BAGI SESI 2004/2005 (IEM COUNCIL SESSION)YANG DIPERTUA / PRESIDENT:Ir. Prof. Abang Abdullah bin Abang Ali

TIMBALAN YANG DIPERTUA / DEPUTY PRESIDENT:Ir. Prof. Dr Ow Chee Sheng

NAIB YANG DIPERTUA / VICE PRESIDENTS:Ir. P.E. Chong, Ir. Vincent Chen Kim Kieong, Ir. Chee Meng Sang, Ir. Mohd Aman bin HjIdris, Ir. Choo Kok Beng, Ir. Neoh Cheng Aik, Ir. Prof. Ishak bin Abdul Rahman

SETIAUSAHA KEHORMAT / HON. SECRETARY:Ir. Oon Chee Kheng

BENDAHARI KEHORMAT / HON. TREASURER:Ir. M.C. Hee

WAKIL STRUKTUR / STRUCTURAL REPRESENTATIVE: Ir. David Ng Shiu Yuen

WAKIL AWAM / CIVIL REPRESENTATIVE: Ir. Gunasagaran a/l Krishnan

WAKIL ELEKTRIK / ELECTRICAL REPRESENTATIVE:Ir. Dr Muhammad Fuad bin Abdullah

WAKIL MEKANIK / MECHANICAL REPRESENTATIVE:Ir. Loh Lim Huat

WAKIL KIMIA & DISIPLIN LAIN / CHEMICAL & OTHERS REPRESENTATIVE: Ir. Ahmad Nordeen bin Mohd. Salleh

COUNCIL MEMBERS:Ir. Dr Ahmad Suhaimi bin Abd Rahim, Ir. Prof. Madya Dr Ibrahim bin Kamaruddin,Ir. Assoc. Prof. Megat Johari bin Megat Mohd. Noor, Ir. Hj. Mohamad Ali bin Yusoff,Ir. Bahardin bin Baharom, Ir. Prof. Dr Chuah Hean Teik, Ir. Dr Wong Chin Chaw,Ir. Lee Weng Onn, Ir. Prof. Dr Siti Hamisah Tapsir, Ir. Chin Mee Poon,Y. Bhg. Dato’ Ir. Hj Abdul Rashid bin Maidin, Ir. Tan Yean Chin, Ir. Peter Tan Hoh You,Ir. Kukanesan a/l Sakthiveil, Ir. Assoc. Prof. Dr Mohd Zamin bin Jumaat,Ir. Prof. Dr Amir Hashim bin Mohd Kassim, Ir. Dr Mohd Yusof bin Abdul Rahman,Ir. Adnan bin Zulkiple, Ir. David Lai Kong Phooi, Ir. Manogaran a/l K. Raman,Ir. Hj Mohd Hassin @ Mohd Hashim bin Daud, Ir. Mohd Nizar bin Hassan,Ir. Assoc. Prof. Lt. Kol. Mohd Hazani bin Hj Shafie, Ir Mohd Rasid bin Osman,Ir. Prof. Dr Ruslan bin Hassan, Ir. Woo Ah Keong, Ir. Yeo Boon Kah, Ir. Yusouf binAhmad,Y. Bhg. Tan Sri Dato’ Ir. Mohd Radzi bin Mansor, Y. Bhg. Tan Sri Datuk Dr Ahmad Tajuddin bin Ali, Y. Bhg. Datuk Abdul Hadi bin Mohd Deros

BEKAS YANG DIPERTUA TERAKHIR / IMMEDIATE PAST PRESIDENT: Ir. Dr Gue See Sew

BEKAS YANG DIPERTUA / PAST PRESIDENT:Y. Bhg. Tan Sri Ir. (Dr) J. G. Daniel, Ir. Chiam Teong Tee, Y. Bhg. Dato’ Ir. Pang Leong Hoon,Y. Bhg. Academician Dato’ Ir. Lee Yee Cheong, Y. Bhg. Dato’ Ir. Abdul Rashid bin Ahmad,Ir. Dr Ting Wen Hui, Ir. Hj Mohd Mazlan, Y. Bhg. Datuk Ir. (Dr) Hj. Ahmad Zaidee Laidin

WAKIL CAWANGAN / BRANCH REPRESENTATIVES:Pulau Pinang - Ir. Vincent Tan Huei MengSelatan - Ir. Steve Chong Yoon OnPerak - Y. Bhg. Dato’ Ir. Hj. Abdul Rahman bin DahanTimur - Ir. Hj. Annies bin Md AriffTerengganu - Y. Bhg. Dato’ Ir. Hj. Mohamad bin HusinNegeri Sembilan - Ir. Hj. Jamil bin IbrahimMelaka - Ir. Hj. Abd Rahim bin ShamsudinSarawak - Y. Bhg. Datu Ir. Hubert Thian Chong HuiSabah - Ir. Lee Tet FonMiri - Ir. Dr Edwin Jong Nyon TchanKedah-Perlis - Y. Bhg. Dato’ Ir. Hj. Abdullah bin Hj. Abbas

LEMBAGA PENGARANG / EDITORIAL BOARD:Ketua Pengarang / Chief Editor – Ir. Assoc. Prof. Megat Johari bin Megat Mohd. NoorPengarang (Bulletin) / Bulletin Editor – Sdr. K.H. ManPengarang (Jurnal) / Journal Editor – Ir. Mohd. Rasid bin OsmanSetiausaha / Secretary – Ir. Mohd. Khir bin MuhammadAhli-Ahli / Committee Member – Y. Bhg. Dato’ Ir. Hj. Abdul Rashid bin Maidin,Prof. Dr Asbi bin Ali, Dr Chuah Teong Guan, Assoc. Prof. Dr Deepak Kumar Ghodgaonkar

AHLI JAWATANKUASA PENERBITAN / STANDING COMMITTEE ONPUBLICATIONS:Pengerusi / Chairman: Ir. Chee Meng SangNaib Pengerusi / Vice Chairman: Ir. Prof. Dr Ruslan bin HassanSetiausaha / Secretary: Ir. Mohd. Khir bin MuhammadPengerusi (Perpustakaan) / Library Chairman: Dr Chuah Teong GuanAhli-Ahli / Committee Member: Ir. Chin Mee Poon, Ir. Mohd. Nizar bin Hassan,Ir. Assoc. Prof. Dr Mohd. Zamin bin Jumaat, Y. Bhg. Dato’ Ir. Hj. Abdul Rashid bin Maidin,Ir. Assoc. Prof. Dr Amir Hashim bin Mohd. Kassim, Ir. Lim Eng Hwa, Ir. Low Ah Peng,Ir. Loh Lim Huat, Ir. Mah Soo, Ir. Look Keman bin Hj. Sahari, Ir. Assoc. Prof. Megat Joharibin Megat Mohd. Noor, Ir. Mohd. Rasid bin Osman, Sdr. K.H. Man, Prof. Dr Asbi bin Ali,Sdr. Karthigesu Muniyandi.

JURUTERAE D I T O R I A L

IntroductionThough challenging, the constructionof any bridge over a heavily traffickedroad can be a nightmare, more so whenthe road is a principal artery leading toand in the vicinity of the city centre.That was exactly what the project teamhad to face when the company wasawarded the job in April 2002 to buildthe 45m span separate deck, dualcarriageway twin-celled box-girderbridge over Jalan Kuching, leading tothe Antah Towers.

The original concept for con-structing the bridge superstructureinvolved mid-deck support andnarrowing of lanes along JalanKuching but this option was soondiscarded owing to the anticipatedmassive inconvenience to the publiccaused by traffic upheaval.

Through creative thinking, the teamcame up with a viable alternativesolution to the problem. It was decidedthat the cobwebs should be dustedaway from the launching gantriespreviously used for constructing thePUTRA Light Rail Transit System Two (LRT2) concrete viaducts and have them adapted for use. Ifsuccessful it would mean no hindranceto traffic flow, no central supports, safeoperation and clean appearancethroughout construction, with a little free advertisement added in as a bonus!

This turned out to be exactly thecase and even though some additionalstrengthening to the boxes wererequired and the bridge deck had to bebuilt in stages (it was not possible forthe pair of steel gantry boxes to fullycarry the 1000 odd tonnes self-weightof the cast insitu deck) the effort wasworth it.

Proposed Vs Adopted DeckConstruction OptionOriginally, constructing the decksuperstructure involved thepositioning of a central support at themedian and reducing the road widthalong Jalan Kuching (Figure 1).

Assembly of heavy duty scaffoldings, placing of steel support beams bycranes, and traffic mana-gement are features of thiserection method.

In the adopted solution, thepast successful performanceof the launching gantries(when they were used toconstruct the entire elevatedportions of the 29.1km LRT2 System, crossing overlive traffic at major roads and railways in the city e.g. at NKVE, LDP, FederalHighway, Jalan Bangsar) was

once again relied upon, albeit now not with full regalia. Only certaincomponents of the launcher, mainly thegirder boxes with the element supportrails and the accompanying launchingnoses, were utilised.

Details of Adopted OptionFigure 2 depicts overall the variouscomponents that make up thelaunching gantry when used forerecting LRT2 viaduct concretesegments. For current usage, only theitems indicated in solid lines wereselected. Basically, two rectangularboxes and two truss end noses whenconnected together form a single line of girder, and the self-launchingcapability of these steel box girders wasmade use of to span them over the busyhighway, and the mode of use of theseboxes was then modified to allow them to act as temporary supports for building the bridge.

Launching SequencePrior to launching, the boxes for eachline of girder were supported ontemporary concrete blocks and joined.The noses were then added and thewhole assembly systematically andcarefully checked, particularly at thebolted connections, to ensure that thegirder was ready for launching. Due tospace constraint, the northernmostgirder had to be pushed and guidedinto position through a curve, whichwas more difficult, while the remaining

LRT Launchers Did The Trick For BridgeSuperstructure Over Jalan Kuching!...............................................................................................................................................................................................

By: Dr Yap Weng Fatt, PATI Sdn. Bhd. (A UEM Builders Berhad Company),BSc. (Jt Hons.), PhD, FIEM, MIES, P.Eng. (M), FICE, AIStructE, CEng.


Figure 1 : Scaffolding option

Figure 2 : LRT2 Launching Gantry

C O V E R S T O R Y


three girders werestraight. The variousstages of thelaunching process areshown in Figure 3.

Launching thegirders over JalanKuching took about a day each time but because of thegradual process andthe non-necessity fortraffic diversion orthe presence of bigmobile cranes, themotorists were large-ly unaware of whatwas going on abovethem and onlynoticed when the boxgirders were in placeand supported on theabutments (Figure 4).

Erection of DeckSupport SystemTo support thefalsework for thebridge deck, steel I-beams were placedby a crane sited atabutment A to spantransversely on theelement support railsof the two box girders(Figure 5). Because of the curved soffit of the deck and the minimum 5.0mheight restrictionrequirement above

the road, the bridge deck had to bebuilt above its final position. To do so,the transverse beams near to both endsof the bridge had to be erected belowthe element support rails. Safetynettings were placed on top of thetransverse beams before plywoodboards were installed to cover fully thewhole area between girders and up toboth abutments. Effectively a totallysealed and safe working platform hadbeen created to allow subsequentworks on the deck superstructure toproceed (Figure 6).

Construction of Concrete BoxDeckAs stated earlier, the two girders werenot strong enough to support fully theconcrete deck superstructure. As suchthe webs had to be constructed asindividual curved base I-beams,starting first with one of the edge websbeing cast at the centre, stressed tocarry its own self-weight, and thenjacked sideways to its final position.This procedure was repeated with theother edge web, and finally the centreweb was cast in position without any

Figure 4 : LRT launcher in position

Figure 5 : Positioning of transverse beams

C O V E R S T O R Y

Figure 3 : The launching process

Stage 1 : ASSEMBLE LAUNCHER

PLAN VIEW

PLAN VIEW

PLAN VIEW

PLAN VIEW

PLAN VIEW

PLAN VIEW

PLAN VIEW

ELEVATION

ELEVATION

STAGE 2 : LAUNCHING THROUGH THE CURVE

STAGE 3 : LAUNCHER’S NOSE REACH JLN KUCHING’S MEDIAN

STAGE 4 : LAUNCHER’S NOSE AT ABUTMENT B

STAGE 5 : COMPLETION OF LAUNCHING

STAGE 6(a) : REMAINING LAUNCHING GIRDERS TO BE LAUNCHED OVER IN SIMILAR

STAGE 6(b) : ALL LAUNCHING GIRDERS IN POSITION


need to shift. The bottom slabs and enddiaphragms were cast next, and finallythe top slabs and cantilever wings toform the twin-celled box decksuperstructure. The whole sequence isdetailed in stages 1 to 7 (Figure 7).Because two pairs of gantry girderswere used, work on both decks couldbe carried out almost concurrently.Once completed, the timber forms andfalsework were removed, followednext by the transverse I-beams usingchain blocks. The box girders wereretracted one by one over the highway(stage 8), and finally the completedbridge deck had to be lowered veryslowly about 1 metre to its finalposition (stage 9).

ConclusionCurrently the bridge is fully completedand vehicles have started plying overit. Construction had been verychallenging but, most important of allto the project team, the objectives thatthey had set out to achieve were fullymet. At least by now, without thegantry boxes blocking the view, thecurious public is aware of what wewere doing as initially, when the steelboxes were first launched over JalanKuching, many people were under theimpression that PATI was constructinganother LRT System in KL! n

Acknowledgement

The author wishes to acknowledge thestrong effort put in by the project teamto resolve the various unexpectedproblems and issues that had surfacedduring the works and complimentsthem on a job well done. Thanks arealso due to our client Ideal AppraisalSdn Bhd for giving us the opportunityto work on this project and for placingtheir trust in our construction method.

Figure 7 : Deck construction sequence

STAGE I : CAST EDGE WEB

STAGE II : SLIDE WEB TO POSITION STAGE IV : SLIDE WEB TO POSITION

STAGE V : CAST MIDDLE WEB

STAGE VI : CAST BOTTOM SLABS AND END DIAPHRAGMS

STAGE VII : CAST DECK AND WINGS

STAGE VIII : REMOVE TRANSVERSE BEAMS& RETRACT LAUNCHING GIRDERS

STAGE IX : LOWERING OF COMPLETEDBRIDGE TO FINAL LEVEL

STAGE III : CAST OTHER EDGE WEB

C O V E R S T O R Y

Figure 6 : Full working platform


IntroductionHot in-place recycling (HIPR) is analternative method of pavementrehabilitation whereby the existingdeteriorated wearing course is remediedby recycling the layer and rejuvenatingits binder properties by adding a smallamount of recycling agent. In addition, acertain amount of fresh asphaltic mixmay be added to improve its aggregategradation or to make-up the quantitydeficiency due to rut depressions.

HIPR method has been previouslyused on the North-South Expressway inthe 1990’s but its use on other roads inMalaysia is almost unknown except forseveral trial demonstrations. In the year2003, the method was introduced onFederal Route 181 (road leading towardsPulau Indah, Kelang) and it is expectedthat several other roads are to berehabilitated with this method.

This article attempts to provide abrief introduction to the HIPR process,equipment for the process, selectioncriteria for the suitable pavementcandidate, mix design, constructionprocess, quality control and finally, theadvantages and disadvantages of thisprocess.

Hot In-Place Recycling ProcessIn general, the HIPR process involves (1)the softening of the existing surface byheating, (2) mechanical removalof the softened pavement surface byscarifying, (3) mixing it with rejuvenator/recycling agent and/or addition of virgin hot mix asphalt (HMA) and (4) placing the recycled material on the original pavement site before (5)compacting it with normal rollers (Figure 1).

There are three types of HIPR processaccording to the American Recycling andReclaiming Association [1], namely:• Surface Recycling/Heater

Scarification – The process involves:(1) heating the existing pavementsurface, (2) scarifying the softenedsurface, (3) adding a recycling agent,(4) mixing the loose recycled material,

(5) spreading and placing therecycled mix with a free floatingscreed, and (6) compacting the mixwith conventional rollers andprocedures. Depths of 20mm to25mm are common for this type ofrecycling method.

• Remixing – The remixing processconsists of the following steps: (1)Heating the pavement to a depth of37.5mm to 50mm; (2) scarificationand collection of RAP in windrow; (3)addition of virgin aggregate,recycling agent, or fresh HMA mix;(4) mixing in a pugmill; and (5)spreading recycled mix andcompacting.

• Repaving – surface recycling iscombined with a simultaneousoverlay of new HMA to form athermal bond between recycled andnew layers. The recycled depthgenerally ranges from 25 to 50mm.

In Malaysia, the most commonmethod presently used is the remixingmethod with a recycled depth of 50mm,as described earlier.

EquipmentHistorically, an equipment using theheater scarification process wasoriginally developed in the 1930s inUtah, U.S.A. However, it is generally

accepted that the first boom of HIRequipment and processes occurredin the 1950s and 1960s, with the advent ofthe repaving process invented by Cutler.The modern era of recycling was initiatedin the mid-1970s, whereby more complexand technologically advanced machinerywere manufactured such as the useof infrared type heaters and the use of stationary teeth or rotating millingheads for the removal of the softenedpavement [2].

The development of HIPR equipmentand process (particularly the remixprocess) have been rapid since late 1980sand early 1990s, enabling existingpavement to be recycled deeper and anacceptable high quality asphaltpavement laid down which iscomparable to other similarrehabilitation methods. Presently, amongthe latest innovations include the use of acombined heating system whereby acombination of hot air under forcedconvection and an indirect low-levelinfrared heaters is used to reduceexcessive heat (Figure 2). This is becauseexcessive heat can damage the asphaltbinder due to accelerated oxidation of thebinder in the pavement [2].

A typical HIPR equipment train(remix process) consists of a preheater,remixer, tipper truck, tandem and tyre

Hot In-Place Recycling: An Introduction..............................................................................................................................................................................

By: Ir. Ahmad Kamil bin Arshad, BEng, MSc, MBA, LLB, P.Eng, MIEM

Figure 1: HIPR Equipment Train: Preheater, Remixer, Tipper, Rollers(Source: http://www.propel.com)

F E A T U R E


roller. The preheater, which is equippedwith clusters of infrared heaters fed withpropane gas, softens the wearing courseby heating the pavement to between140°C to 170°C.

The remixer includes a receivinghopper for additional mix, infraredheaters and a rotating scrarifier (Figure3). The scarifier unit scarifies the softenedpavement and the rejuvenator is sprayed on the reclaimed material.It is then augered to the center of themachine where it enters a pugmillmixer and is mixed thoroughly with thevirgin mix. After thorough mixing, thematerial is discharged from the mixer asa windrow in front of the auger andscreed [3].

The blended mix is then placed on theoriginal pavement site by a compactingscreed. Normal compaction is carried outwith a steel tandem roller and rubbertired roller.

Selection Criteria of PavementCandidateThe HIPR process is used to treat surfacedistress such as surface cracking, minorrutting and raveling. It is not suitable forbase or subgrade related distresses. It isbasically a preventive maintenancetreatment whereby the damaging effectsof surface distresses is mitigated earlyto prevent further deterioration of thepavement structure. A good candidatepavement for rehabilitation with HIPR isany hot mix asphalt pavement witha stable base, adequate drainage,and does not have the followingcharacteristics:1) Failures that are base/subgrade

related.2) Rutting more than 50% of the depth

to be recycled.3) Mat thickness of less than 75mm.4) Cracks deeper than the scarifying

depth.5) Low binder content – less than 4%.6) Poor or soft aggregates.7) Large aggregates – larger than 19mm

diameter.8) Evidence of stripping9) Existence of geofabrics material such

a petro-mat at the scarified depth.

To determine a candidate pavementfor HIPR, the following must be carriedout:1) Structural evaluation and visual

inspection of the candidatepavement.

2) Obtaining cores of the roadwaysurface to determine:

a) Mat thickness.b) Aggregate size, hardness and

gradation.c) Percent of asphalt.d) Existence of geo-fabric material

such a petro-mat and its depth.e) Evidence of stripping.

3) Reviewing records from the “as-built” drawings of the roadway.

4) Interviewing field maintenancepersonnel.

After a candidate pavement has beenselected, a qualified materials engineershould conduct further testing at his/herdiscretion.

Mix DesignHIPR mix designs are generallyperformed to restore the characteristics ofthe existing aged asphalt pavementsimilar to those of virgin HMA. The twomajor steps in mix design procedure arematerial evaluation and mix design.

The objective of the materialevaluation step is to determine theimportant properties of the componentmaterials. The steps involved aresampling, determination of properties ofin-situ asphalt pavement material orRAP and recycling agent.

The mix design step consists of using the Marshall Design Method to determine the type and percentage of recycling agent required. In summary, the overall mix design process involves the following steps:• Evaluation of the existing aged

asphalt pavement including asphaltbinder, aggregate gradation and mixproperties.

• Determining whether the existingasphalt binder needs rejuvenation.

• Selecting the type and amount ofrecycling agent.

• Determining the need for andamount of admixture includingaggregate gradation, type andamount of asphalt binder.

Figure 2: HIPR machine using combination of hot air under forced convection and low levelinfra-red heating system [2]

Figure 3: Various components of a typical remixer machine [3]

F E A T U R E


• Preparing and testing both asphaltbinder and mix specimens in thelaboratory.

• Evaluating tests results anddetermining the optimumcombination of admixture andrecycling agent.

ConstructionPrior to the HIPR process, areas withisolated base and/or subgrade failures isreconstructed first up to the binder layer.The pavement surface is then cleaned ofany loose and deleterious material suchas silt, dirt and other debris by broomingor other cleaning methods.

The pavement is heated with apre-heater (Figure 5) to a temperature ofabout 130°C to 150°C but not more than160°C to 170°C to prevent burning andcharring of the pavement surface. Theheated pavement is then immediatelyscarified using the remixer machine(Figure 6), before being added with thespecified quantity of recycling agent andfresh ashphaltic mix. The recycledmaterial and the fresh mix is blended inthe remixer’s pugmill before being laidon the existing pavement with theattached paving screed on the remixermachine.

The HIPR surface is then compactedusing the normal compaction proceduresused in the conventional laying method.The JKR Specifications specified thatthe minimum temperature before thestart of rolling must be 110°C toprevent stiffening of the mix duringcompaction. According to the asphaltInstitute, below 85°C, the mix hasstiffened to such extent that compactionis no longer effective. CSIR of SouthAfrica recommends that rolling shall takeplace between 90°C to 130°C for 80/100penetration grade bitumen mix.

Joints poses aspecial problemfor the HIPRprocess as certainprocedures have tobe followed toachieve therequired finishedHIPR surface. TheJKR Specificationsrequire that heatingshall extend at least100mm intoadjacent mat toenable a hot-on-hotlongitudinal joint tobe constructed [5].

Sometimes this isnot possible due to space constraints (e.g.in a dual-two road, requirements to open one lane to traffic may preventthe extension of heating). Propercompaction at the joints is vital to prevent joint cracks and also to achievea neat surface finish.

Quality Control In general, three types of specificationsare used: (1) method, (2) end-result, and(3) a combination of method and end-result. JKR Malaysia currently adopts aspecification which is a combination ofmethod and end-result specification [5],This ensures that proper equipment andwork procedures are followed by thecontractor and at the same time thespecified performance of the end productis achieved.

Some recommended guidelines forquality control (QC)/quality assurance(QA) of the recycled mix in HIPR processare as follows [4]:• Depth of scarification is measured to

ensure adequate thickness of therecycled layer.

• Application rate of recycling agent –the quantity used is calculated andthe asphalt content before and afteradding recycling agent is calculatedto ensure that it is within thespecified range (generally 5–7%).

• Fresh bituminous mix addition rate is calculated from the quantity used.

• Temperature of the recycled mixbehind the screed is measured toensure that a minimum temperatureof 110°C is achieved beforecompaction commences.

• Coring of laid recycled wearingcourse to determine the compactedthickness, Marshall Density andbinder penetration.

Advantages and Disadvantagesof HIPR

Advantages of HIPRThe advantages of hot in-place recyclingare the following: (1) conservation ofenergy and materials, (aggregates,asphalt and transport fuel) (2) no millingwaste disposal (3) pavement geometricsare preserved or restored, (4) surfacedistresses such as cracks and minorrutting not caused by structuralinadequacy can be corrected, and (5)existing surface mixes can be modified.

The other advantages of hot in-placerecycling are: (6) surface frictionalresistance can be improved, (7) theprocess is relatively cheap, (8) themethod needs less traffic controlcompared to the other rehabilitation andtechniques.

Disadvantages of HIPRThe disadvantages of HIPR include thefollowing: (1) high acquisition cost of theHIPR equipment, (2) a dedicated andskilled team of operators/workers isrequired, (3) existing pavementproperties must be relativelyhomogenous for the process, (4) wherethere are manholes and bridge joints,manual paving operations must becarried out, (5) four legged intersectionsmay not be suitable as there is difficultyof obtaining the proper crossfall usingthe HIPR equipment, (6) excessive smokeparticularly where there is dirt andpaintwork, (7) length of the HIPRequipment may be unsuitable for placeswith limited access and sharp turningradius such as urban areas.

Conclusion The HIPR process is an alternative toother conventional methods such asmill and pave in addressing surfacedistresses as explained above. The mainattraction of this process is that resources

Figure 5: Heating the pavement surface witha preheater

Figure 4: The actual remixer machine (back view) [3]

F E A T U R E


are saved by the use of recycled materials and cost savings is also possible as compared to the conventional mill and pave method. However, there are limitations to this process as it is less flexible in addressing pavement with irregular shape orwidth and require a dedicated team of skilled operators andsupport workers. An understanding of the limitations of theprocess and machinery is essential in choosing the correctpavement candidate for this method. n

Figure 6: Sacrifying the sftened heated pavement [4]

REFERENCES

[1] Marti, Michael M. & Mielke, Andrew, “Synthesis of Asphalt Recycling in Minnesota,” Minnesota Department of Transportation, St. Paul, Minnesota,June 2002.

[2] Terrel Ronald L. et al., “Progress In Hot In-Place Recycling Technology,” Paper prepared for 8th International Conference on Asphalt Pavements, Seattle, August 1997.

[3] Wirtgen, “Materials and Process Procedure Principles for The Hot Recycling Process,” Wirtgen, Windhagen, 2003.

[4] Kandhal, Prithvi S. & Mallick, Rajib B., “Pavement Recycling Guidelines for State and Local Governments,” Publications No. FHWA-SA-98-042, Federal Highway Administration, Department of Transportation, December 1997.

[5] JKR Malaysia, Specifications for Hot In-Place Recycling, 2003 (unpublished).

[6] Sholar, Gregory A. et. al., “Evaluation of Two Hot In-Place Recycling Projects”, Research Report No. FL/DOT/SMO/02-455, State Materials Office, Florida Department of Transportation, July 2002.

F E A T U R E


Dear Chief Editor,

SOIL NAILING & GUNITING

I read with intense interest the seminarreport on soil nailing & guniting written by Ir.Yee Yew Weng in the October 2004 issue of theJurutera Bulletin. I’d like to commend the highquality of the report writing. Although I didnot have the opportunity of attending theevening lecture due to reason of distance,there are several points I’d like to add whichmight be of benefit to the reader.

The statement “Soil nails need to extend tosufficient length beyond the active zone or anyplane of weakness to overcome externalstability…” may best be comprehended in thefollowing manner: The soil in front of thelikely failure plane is termed the active zoneand that behind the failure plane the passivezone. Essentially soil nailing can be employedto tie these two zones together and thusprevent failure. The design process assumes acertain shape of failure plane which can takethe form of a single plane, a twin plane (twinwedge), circular, log spiral or others. Differentgeometries take slightly different calculationsbut all in all the methods require an out-of-balance force or moment to be calculated anda system of nails deployed to resist it. Inessence, the two strength aspects of soil nailperformance are the inherent rupture strengthof the nails themselves and the pull-outresistance of the soil nails from the resistant(passive) zone of the soil.

Eurocode 7 gives some guidance on thegeotechnical matters relating to soil nailingand the pullout resistance partial factors fordesign are discussed in Section 2 and in AnnexB. Valuable design information can also befound in the respective BBA Certificate of thesoil nail product. The BBA Certificate willnormally include technical information withregards to the design, materials specification

(tensile strength, design strength, pull-outresistance, chemical resistance, hydrolysis,effects of temperature and durability), andconstruction methods of soil nailingapplications.

The stabilisation of slopes using soil nailprinciples differs considerably from theground anchoring approach. Groundanchorages are founded outside any potentialslip planes or slip circles and are prestressedagainst a major structure to distribute the soilretaining force at the slope face. The facing ofthe soil-nailed structure is not a majorstructural load-carrying element but ratherensures the local stability of the soil betweenreinforcement layers and protects the groundfrom surface erosions and weathering effects.

Soil nails are installed at a much higherdensity and generally remain passive. Theyremain unstressed until nominal soilmovement mobilises the tensile capacity of thesoil reinforcement. Subject to adequate soildensity, nail lengths, strength and bondcapacity, the nailed soil volume may belikened to a reinforced gravity structureretaining and stabilising the slopes.

The designer must always remember thatsoil nailing is an in-situ technique and that heshould consider the possible options formodifying the design should unforeseenground conditions be encountered on site andas construction proceeds from the “topdown”. Ground water and infiltration ofrainfall have a profound effect on soil nailing.This is especially the case when increasedporewater pressure may reduce both thestability of the soil and the pull-out resistanceof the nails. The designer should always try tominimise the ingress of water to the structureand also include provision for an increase inporewater pressure at some time during thelife of the structure. Where inundation couldoccur special consideration is required toverify the suitability of the location for soil

nailing. Examples of this include a wall belowa major water main and main open drain for amajor development.

The nails are generally made of steel,although other materials, in particularglassfibres are now becoming moreacceptable. Designer should therefore lookinto all options on the selection of soil nail fora particular site.

Currently, most reinforced slope designhas been carried out per HA68/94 orBS8006:1995. HA68/94 was published in 1994in the UK DOT/HA design manual for roadsand bridges (Volume 4, Section 1, Part 4). Themanual gives design methods for thereinforcement of highway slopes by reinforcedsoil and soil nailing techniques. It is a limitstate design standard with 60 year design lifeand caters for slopes exclusively ≤ 70°.

HA68/94 is the first “unified” designmethod for slopes reinforced by geosyntheticsor soil nails. The design method givesreinforcement layout but assumes a competentfoundation. If the foundation is notcompetent, or if the bearing material is notsignificantly better than the slope material,then underlying slip mechanisms should bechecked by alternative means (Bishop’sMethods, etc.) and independently improved.

Like HA68/94, BS8006:1995 is a limit statedesign standard code of practice forstrengthened/reinforced soils and other fills.BS8006:1995 is based on modern soilmechanics principles with partial safetyfactors back-calculated from existingexperience. It is however viewed asincompatible with the upcoming Eurocode 7.

HA68/94 is better preferred by mostdesigners as it uses a simple two-part wedgemechanism. It is a full design method givingan economical reinforcement layout. n

IR. ALBERT TAM KIN WAHIEM MEMBERSHIP: F05941

Dear Chief Editor,

MY VIEW TO IMPROVEOUR ‘PROGRESSIVE’ SOCIETY

I was travelling on the PLUS highway onthe way to Singapore when I encountered avery bad experience on the road. It wasChristmas eve and there were quite a lot ofcars on the road. I was especially taken abackwhen a car which I wanted to overtake kept onhogging the fast lane and blocking my way toovertake. All I did was flashing my lights toalert the driver of that car that I was coming‘fast’ and wanted to overtake. The driverblocked the road and went faster when I triedto overtake from the left. He purposedly didthat because the driver allowed other cars toovertake but not me.

This is a bad attitude of Malaysian drivers.Sometimes we drive according to ourtemperament and emotions. This happensespecially on busy and jammed roads.

Motorists are getting impatient and restless.No wonder we have road bullies on our roads.

As a reponsible citizen and engineer, I amaccountable to society. We have a socialreponsibility. How we behave can actuallychange society. It is a tall order. Don’t thinkthat we are just a fraction of the Malaysianpopulation. See, if we as reponsibleindividuals and intellectuals try to changesociety, others will follow if they see what wedo is good. The proper ‘way of life’ will slowlysip into society. Remember there are otherprofessional institutions as well which arepropagating good values as well. They are theaccountant’s association, the medicalassociation, etc. We could be taking the leadinto doing all these. But, what is wrong withthat?

Malaysia is gearing towards a progressiveand an improved society. So let the seeds of‘civilisation’ grow in our heart. One day, weare going to be a developed country. Does our

standards and quality of life meet thestandards of other developed nations? Let'sponder over it. Together we can make thedifference. Well, of course here, I am not onlytalking about attitude in using the roads, thereare many other things associated with civic-consciousness. For example, throwing ofrubbish and unused plastics bags, spitting,abuse of public amenities (vandalism),scratching and knocking on others car whenparking, etc.

So, as engineers, let us start instilling theright attitude and values in ourselves so thatthe nation can be propelled to a greater height.Some of us are policy makers and holdresponsible positions. We can educate peopleby using our authority in this sense. Just askyourself, don't you want a better tomorrow forour children and future generations! n

SDR. NG KENG PENGIEM MEMBERSHIP: G15739

L E T T E R T O E D I T O R


AbstractOver the years, there is an increasingoccurrence of damage to buildings in thecountry caused by ground settlement.Some of the cases are due to inexperienceand the failure to understand thefundamentals of engineering.

The intention of this paper is toprovide awareness to young engineerson the need to consider the allowablesettlement of the building and structure-soil interaction behaviour. Engineersshould recognise potential problemsassociated with building on difficultground conditions. Not too long ago theterm negative friction was uncommonbut now, engineers are more aware of theeffects of negative friction. As casehistories of failures are highly sensitive,none are mentioned in this paper.

IntroductionWith the tremendous growth of theconstruction industry in Malaysia overthe last two decades, buildings are nowincreasingly being built on weakergrounds. There is a need for engineers toconsider the allowable settlements of thestructures in their designs andunderstand the basic structure-soilinteraction behaviour. Engineers have toestimate or predict the amount ofmovements and whether the structurecan tolerate it.

Traditionally the structural engineerdesigns both the super-structure and the foundation of the proposed building. Most foundation designs are socalled routine designs with littleconsideration for allowable settlements.Experienced geotechnical engineersshould be employed to designfoundations of complex nature andimportant structures. In recent yearsthere have been a growing numbers ofthese experts.

Settlement problems are not confinedto high rise buildings and importantstructures and indeed a number of singlestorey houses in this country haveexperienced excessive differentialsettlements, which resulted in very

expensive repair works. Many werebeyond repair and had to be rebuilt.

Building on weak soil or difficultgrounds does not always have to meanhigh safety factors. If the superstructureand foundation are studied in relation tothe ground movements, an economicaldesign may be possible.

Total and differentialsettlementsDesign engineers should consider boththe total and differential settlements butit is the differential settlement that isreally of concern. Often a uniform totalsettlement of not more than 300mm doesnot cause any damage to a buildingexcept to its utility services. A classicexample is the “Palacio de las BellasArtes” or the “Palace of Fine ArtsBuilding” in Mexico City (Lambed andWhitman) where the building has settledby more than 3m and is still serviceable.Silos and tanks for storage of fluids cantolerate large total settlements.

Differential settlement is basicallywhen one part of the building settlesmore than the other part. When thedifferential settlement is excessive,building will distort (Figure 1) and sufferdamage, which may sometimes bedevastating. The most famous case ofdifferential settlement is the LeaningTower of Pisa, where the South side of the tower settles more than the North side.

Differential settlement is normallyexpressed as the angular distortion,which is defined as ratio where isthe difference in settlement between twopoints and is the distance between thepoints.

Allowable settlementsIt is generally acknowledged that threecriteria should be satisfied whenconsidering the limiting movements of abuilding (i) visual appearance; (ii)serviceability or function; and (iii)stability or structural failure (Figure 2).However, the amount of allowablesettlements is usually governed by theavoidance of cracks in walls and finishes. Any jamming of doors andwindows, breaking-up of sidewalks and drains, may signify possibledifferential settlements. Unsightly

“How Much Settlement Do You Allow For In Your Buildings?”...............................................................................................................................................................................................

By : Ir. Yap Keam Min, FIEM, MICE, MIEAust, P.Eng, C.Eng

Figure 1 : Distortion of building due to excessivedifferential settlement

Figure 2 : Structural failure

Figure 3 : Severe cracks due to differentialsettlement in the living room is not

a welcomed sight

F E A T U R E


cracks are definitely not welcomed in ourliving room (Figure 3). Besides, any crackwhether structural or not will causeconcern and alarm to the layman.

The amount of allowable settlementdepends on many factors and due to itscomplexity, most researchers have reliedon studying and observing theperformance of actual buildings todevelop empirical methods to determinethe magnitude of settlements allowed.Perhaps one of the most famous workson the topic of allowable settlements isby Skempton and MacDonald (1956) whostudied the performance of ninety-eightbuildings of load bearing wall, reinforcedconcrete and steel frame constructionfounded on various foundation systems.Not all buildings that had differentialsettlement sustained damages, only fortybuildings had been damaged in varyingdegrees as the result of settlements. Thedamages were classified into functionalor serviceability, architectural andstructural damage. Skempton andMacDonald gave the angular distortionlimits for the cracking of walls or panels

in conventional frame buildings or load bearing brickwall buildings as1/300 and for structural damage tocolumns and beams as 1/150. Theirrecommendations for the allowablesettlements are given in Table 1.However, the frame structures and load bearing brickwall buildings shouldhave been treated separately as the load bearing brickwall is very muchmore sensitive to movement.

Bjerrum (1963) gave a range ofangular distortion limits for variousconditions (Figure 4). The values for thecrack in the panel walls and structuraldamage are in good agreement withSkempton and MacDonald.

Sowers (1962) summarised hisstudies into three modes of settlements:(i) total settlement, (ii) tilting and (iii)differential movement (Table 2). It showsthat simple steel frames can tolerate largedifferential settlements, whereas highcontinuous brick walls are highlysensitive to movement. The settlementlimit for buildings with sensitivemachine operations is stringent.

Terzaghi (1938) studied theperformances of many buildings andconcluded that most ordinary structurescan tolerate a differential settlement of20mm between adjacent columns.Terzaghi and Peck (1967) also suggestedthat the differential settlement is unlikelyto exceed 75% of the maximumsettlement, which means the totalsettlement the frame building canwithstand is 25mm. This may beprobably why most of the buildingfoundations are designed so that the totalsettlements do not exceed 25mm

Few building codes give specificvalues for allowable settlements. It isinteresting to note that the old U. S. S. R.(1955) building code (Table 3), which isbasically from the work by Polshin andTokar (1957) in the former Soviet Uniongave permissible differential settlementswhich are still relevant today.

The subject of allowable settlementshas to be considered in difficult groundconditions and some of the typicaldifficult grounds in Malaysia are asfollows:1. Ex-mining land - Normally consists of

tin mining residuals, which is verysoft silty clay commonly called slime(Figure 5). These grounds are highlycompressible and as it is man-made,

Figure 4 : Limiting angular distortions (Bjerrum, 1963)

Figure 5 : Typical slime in ex-mining land. Lookssolid but is very soft just below the surface.

TABLE 1 : DAMAGE LIMITS FOR LOAD BEARING WALLS OR WALL PANELS IN FRAME BUILDINGS(SKEMPTON AND MACDONALD, 1956)

Criterion Isolated foundations Rafts

Angular distortion 1/300

Greatest differential settlement : Clays 45mm

Sands 30mm

Maximum settlement : Clays 75mm 75mm to 125mm

Sands 50mm 50mm to 75mm

Considerable cracking in panel walls and brick walls.

Safe limit for flexible brick walls, h/l < 1/4

Limit where structural damage of general buildings is to be feared.

Limits where difficulties with machinery sensitive to settlements are to be feared.

Limit of danger for frames with diagonals.

Safe limit for buildings where cracking is not permissible.

Limit where first cracking in panel walls is to be expected.

Limit where difficulties with overhead cranes are to be expected.

Limit where tilting of high, rigid buildings might become visible.

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Note l = distance between adjacent columns that settle different amounts, or between any two point that settle differently. Higher values are forregular settlements and more tolerant structures. Lower values are for irregular settlements and critical structures.

TABLE 3 : PERMISSIBLE DIFFERENTIAL SETTLEMENT BY U. S. S. R. BUILDING CODE (1955)(FROM POLSHIN AND TOKAR)

Description of standard value On sand or hard clay On plastic clay

Slope of crane runway 0.003 0.003

Difference in settlement of civil and industrial building column foundations :

for steel and reinforced concrete structures, 0.002l 0.002lfor end rows of columns with brick cladding, 0.0007l 0.001lfor structures where auxiliary strain does not arise during nonuniform 0.005l 0.005lsettlement of foundations (l = distance between column centres)

Relative deflection of plain brick walls :

for multi-story dwellings and civil buildings at l/H ≤ 3 0.0003 0.0004at l/H ≥ 5 0.0005 0.0007

(l = length of deflected part of wall; H = height of wall from foundation footing)

for one-story mill buildings 0.001 0.001

Pitch of solid or ring-shaped foundations of high rigid structures 0.004 0.004(smoke stacks, water towers, silos, etc.) at the most unfavourable combination of loads

TABLE 2. ALLOWABLE SETTLEMENTS (SOWERS, 1962)

Type of movement Limiting factor Maximum Settlement

Drainage 15-30cmAccess 10-60cm

Total Settlement Probability of nonuniform settlement : Masonry walled structure 2.5-5cmFramed structures 5-10cmSmokestacks, silos , mats 7.5-30cm

Stability against overturning Depends on Height and WidthTilting of smokestacks, towers 0.004lRolling of trucks, etc. 0.01l

Tilting Stacking of goods 0.01lMachine operation - cotton loom 0.003lMachine operation - turbo generator 0.0002lCrane rails 0.003lDrainage of floors 0.01 - 0.02l

High continuous brick walls 0.0005-0.001lOne-story brick mill building, wall cracking 0.001-0.002lPlaster cracking (gypsum) 0.001l

Differential movement Reinforced-concrete-building frame 0.0025-0.004lReinforced-concrete-building curtain walls 0.003lSteel frame, continuous 0.002lSimple steel frame 0.005l

F E A T U R E


can be very variable. The worstcondition is where limestone bedrockis overlain with very soft slime.

2. Marine soil - The top 20m of the soilstrata usually consist of highlycompressible silty clay with SPT Nvalues of zero. The weak compressiblesoil makes foundation design verytricky. The apron and services areoften overlooked and although thestructure is stable, settlement of apronand drains are common.

3. Backfill - Deep fill can be a concernespecially if poorly compacted.Indiscriminately filling with rock andboulders can cause serious problemsfor the foundation engineer (Figure 6).Modern day construction schedulesdo not seem to allow any time fornormal consolidation. There areinstances where piles are driven whilethe mining pools are being filled.

4. Landfills – Contains loose waste andorganic matter. The decomposition oforganic matter makes the landfillhighly compressible and veryvariable.

5. Cut and fill – Often in constructionwork, buildings have to beconstructed on cut and fill ground.

The part of the building sitting on thefill portion may settle more than thaton the cut area resulting in differentialsettlement.

The allowable settlement depends on thefollowing:1) Type of structure or construction

material - A steel frame structure cantolerate a much larger differentialsettlement than a loading bearingbrick wall building. A lot of houses inearthquake-prone areas are made ofwood, which is flexible.

2) Use of the building - Cracks in afactory may be acceptable whereasany crack in a house is often ofconcern. Water retaining structuresand reinforced concrete flat roofscannot bear much differentialsettlement because of theirrequirements for water tightness.Important structures are also designedfor less settlement.

3) Rigidity of the structure - Flexiblestructures can tolerate greaterdistortions. For example, simple steelframes are more flexible thancontinuous steel frame although theyare constructed of the same materials.

4) Type of foundation - Raft foundationscan tolerate greater amounts ofdifferential settlements and are oftenused in highly variable grounds toreduce settlements.

5) Location - Construction of newbuildings especially those involvingdeep excavation and piling worksmay lead to additional settlement ofthe adjacent buildings. It is importantto study if the nearby structures cantolerate the additional settlements. Forinstance the design of a temporarystructure may allow for a larger totalsettlement that may not be toleratedby adjacent buildings.

Structure-soil InteractionAs mentioned previously, it is necessaryto understand the basic structure-soilinteraction behaviour when designingfor buildings located on difficultgrounds. Structural engineers do notwant any settlement on their buildingsand obviously that's not really possibleespecially where buildings are to be builton weak ground. The foundationengineer has to estimate the mode andamount of settlements based on theground condition and the structuralengineer has to predict how muchdistortion the structure can tolerate. Thefoundation engineer and structuralengineer have to work closely to producethe best possible design for the building.

One of the most important factors inthis relationship is the rigidity of thestructures. A flexible structure has littleload transfer and can take greaterdistortion than a stiff structure. However,a rigid structure has larger capacity totransfer load and hence reducedifferential settlements. An example of aflexible structure is a simple steel frameand a steel frame structure with manydiagonal bracing is very rigid. (Coduta1994)

Obviously it is costly to stiffen astructure, which may be done withbracing, shear wall and ground beams.Little (1969) gave an example of aparticular building where the cost ofpreventing cracks by resistingmovements in the structure andfoundation can be easily more than tenpercent of the total cost of the building.With a flexible structure, it is best toavoid having finishes and machinery,which are sensitive to movements,although such machinery can be foundedon a separate foundation.

The question of whether to design aflexible structure to accommodate themovements or a rigid structure to reduce differential settlements should bebased on experience and engineeringjudgement.

Load bearing brickwall construction,which is highly sensitive to movements(Figure 7), may not be a suitable form ofconstruction in highly compressible soils.Skempton and MacDonald (1956) gavean example of a five-storey building ofload bearing brickwall constructed on a1.2m raft in filled ground. Damage wassevere, with cracking of all the walls eventhough the building was founded on athick raft. Another example of loadbearing brickwall failure in Malaysia isthe construction of single storey houses,

Figure 6 : Backfill indiscriminately filled withboulders can be a nightmare for foundation

engineers

Figure 7 : Brickwall is highly sensitive tomovements

Figure 8 : Settlement of walkway and apron,common occurence in soft ground such as

marine soil

F E A T U R E


built on reclaimed land which haverequired expensive underpinning repairworks. With the introduction of manynew building systems such aslightweight concrete, precast concrete tiltup panels, etc, engineers should evaluatethe effect of movements on thesesystems.

Every construction is a full-scale test;therefore the engineers can learn a lotfrom studying the behaviour of similarconstruction, especially from case ofhistories of failures.

Construction works such as deepexcavation, dewatering, pile driving andtunnelling will benefit from experience ofprevious works. The design engineershould be aware of possible movementsof the soil and its effect on the adjacentproperties.

ConclusionWhat is the allowable settlement of abuilding? This question was raised tomany local design engineers and theauthor got a variety of answers, e.g. zerosettlement, 12mm, 25mm; and someengineers never considered. The answeris that there is no fixed value but dependson many factors, the most importantbeing the type and use of the buildingand the stiffness of the structure.

The values of the settlement limitsgiven in the tables and figure provide a good guide to the design engineer but should be followed with goodengineering judgement. It can beconcluded that for a typical concreteframe building, the limit of the angulardistortion for cracking in the walls is1/300 and for structural damage, 1/150.

According to Terzaghi (1938), mostordinary buildings can tolerate a

differential settlement of 20mm and atotal settlement of 25mm. This isprobably the basis of our foundationdesign where the static load test for piles normally allows for a maximumsettlement of 25mm at twice the working load.

The problem of differentialsettlements may be solved either bydesigning the structure to accommodatethe movement or to resist it. Whendesigning a building where largesettlements are expected, it may also beworthwhile to study the performance ofexisting nearby structures. You do notwant to allow for large settlement whenthe adjacent building is a historicalbuilding.

The steel structure is most tolerable tomovements whereas the load bearingbrickwall is the least and thereforeshould be avoided in difficult soils. Theengineer should also recognise the needto design for the possible settlement ofthe apron, walkways and drains in softsoil (Figure 8 & 9). With knowledge of theallowable settlement, it may be possiblefor engineers to choose the properfoundation and type of structure for aneconomical and safe design.

A number of building failures hadoccurred because of incorrect choice offoundation or structural system. Thedesign engineer should be aware ofpossible settlement problems beforedeciding on the type of structure andfoundation. As a wise man once said,identifying the problem is half the battle won. n

REFERENCES

Bjerrum, L. (1963). "AllowableSettlements of Structures,"Proceedings of European Conferenceon Soil Mechanics and FoundationEngineering, vol. 2, Wiesbaden,Germany, pp. 135-137.

Burland, J.B., Broms, B.B., DeMello,V.F.B. (1977). "Behaviour ofFoundations and Structures: State ofthe Art Report." Proceedings of theNinth International Conference onSoil Mechanics and FoundationEngineering, Japanese GeotechnicalSociety, Tokyo, vol. 2, pp. 495-546.

Coduta, D. P. (1994). FoundationDesign, Principles and Practices.Prentice-Hall, Englewood Cliffs, N. J.,796 pp.

Day, R.W. (1999). Geotechnical andFoundation Engineering. McGraw-Hill, New York

Lambe, T. W., and Whitman, R. V.(1969). Soil Mechanics. John Wiley &Sons, New York, 553 pp.

Little, M.E.R (1969): Discussion -Session 6. on Design for movement inBuildings. The Concrete, London.

Peck, R.B., Hanson, W.E., andThornburn, T.H (1974). FoundationEngineering. John Wiley & Sons,New York, 514 pp.

Polshin, D.E., and R.A. Tokar (1957),"Maximum Allowable Non-UniformSettlement of Structures," Proc. 4thIntern. Conf. on Soil Mech. AndFoundation Engineering, i, 402-5.London.

Skempton, A. W., and MacDonald, D.H. (1956). "The Allowable Settlementof Buildings." Proceedings of TheInstitution of Civil Engineers, PartIII. The Institution of Civil Engineers,London, no. 5, pp. 727-768.

Sowers, G. F. (1962). "ShallowFoundations," Chap. 6 fromFoundation Engineering, G. A.Leonards, ed. McGraw-Hill, NewYork.

Terzaghi, K. (1938). "Settlement ofStructures in Europe and Methods ofObservation, " Transactions, ASCE,vol. 103, p. 1432.

Terzaghi, K., and Peck, R.B. (1967).Soil Mechanics in EngineeringPractice, 2nd ed. John Wiley andSons, New York, 729 pp.

Wayne C. Teng (1976). FoundationDesign. Prentice-Hall of India, NewDelhi.

Figure 9 : Settlement of drain and services in soft soil

F E A T U R E

In May 2001, the MalaysianGovernment announced the Small

Renewable Energy Power (SREP)Programme, targeting 5% of thecountry’s total electricity generation tocome from renewable energy (RE)sources by the year 2005. This wassupposed to alter the make-up of thecountry’s fuel dependency on hydro,coal, gas and fuel oil, by accommodatinga new fifth fuel source.

The Ministry of Energy,Communications and Multimedia,Malaysia, forecasts our total maximumelectricity demand in the year 2005 to beabout 15,417 MW [1]. Thus there isessentially a target of about 770 MW to begenerated from RE sources, initially.

Under the provisos of the currentSREP programme, however, each REpower plant may only sell up to 10 MWto the grid, hence there are potentially atleast 77 such power plants that need to beinstalled nationwide to meet the policyobjective.

However, it has been reported thatthe government has so far only approved48 SREP projects with total capacityamounting to only 304 MW [2], whichfalls far short of the goal. Out of thereported 48 approved projects, TNB hasdisclosed that only two REPPAs (RE Power Purchase Agreements) had been signed at the end of the year2003, totaling only 5.2 MW of capacity, with another 15 MW from twoother developers in Sabah undernegotiation [3].

Thus, it appears most likely thatelectricity generated from RE sources inMalaysia will thus fall very far short ofthe target set by the government.

So, what are the reasons for theapparent failure to build up renewableenergy capacity, and what needs to bedone to overcome it?

EFB Biomass – Malaysia’s MostPromising Renewable EnergyResourceThere are many sources of renewableenergy such as wind, wave, solar-

photovoltaic, biomass, biogas, municipalwaste, and mini-hydro, which are allabundantly available in Malaysia.Harnessing each of these energy sourcesfor economical electricity generationhowever, poses different challenges dueto the nature of the RE source, or rawmaterial.

Currently most SREP developershave been preoccupied with setting upRE power plants based on palm oilempty fruit bunch (EFB) biomass, due tothe abundance of EFBs, the easilydeployable and manageable powergeneration technology for this type ofmaterial, and the large number ofpotentially viable sites available witheasy access to the grid.

EFB Biomass Power PlantTechnologyPalm oil empty fruit bunches (EFBs) arealready burned in most of the existingpalm oil mills, generating heat which isrecovered in a heat recovery boiler toproduce steam, which in turn drives asteam turbine coupled to a generator.However, the electricity generated inthese mills is not grid connected, and isused solely to meet the mill’s powerrequirements.

As these units have been designed, atinception, with the purpose of providingcaptive power for the mill’s operationsalone, they are generally not suited, noreasily adaptable, for grid connectedelectricity supply on a competitivecommercial basis.

Grid connected power generators arerequired to have a high rate ofavailability (typically 8000 hrs perannum), and be despatchable on a 24hour basis, if they are to operate as acommercially viable independent powergenerator, in much the same way asIndependent Power Producers (IPPs).

The majority of palm oil mills operatewith varying capacities on a seasonablebasis, running 12 hours a day, resulting inpoor availability. Furthermore low costdesign approaches at the onset result inlow operating levels of efficiency.

As a result, palm oil millers buildingnew facilities and wishing to partici-pate in the SREP programme need to incorporate design features to ensure high efficiency, high availabilityand suitability to electricity despatchrequirements, which generally resultsin comparatively higher capitalinvestment cost.

Project Viability ConsiderationsPower project developers will generallyseek opportunities to ideally build aplant at the lowest acceptable cost,utilising the lowest cost fuel, completeplant construction within the shortesttime frame, and sell electricity at thehighest price obtainable.

Contributing factors to the success ofthe project are discussed further below.

a) Plant Investment CostA 10 MWe capacity standalone EFBbiomass power plant is estimated to cost around RM50–60 million. Gridinterconnection costs may add another RM2–3 million to the projectcosts, from the need to construct a transmission line to the nearestavailable grid interconnection point. The owner’s project management and administration costs, land costs, as well as financing costs add further tothe total project cost.

b) Fuel CostsAs with most power plants, fuel cost hasdirect bearing on electricity productioncost. Palm oil millers tend to regard EFBsas available free of cost since it is a wasteproduct from the milling process. If thebiomass power plant was built adjacentto the mill, then perhaps this assumptionmay be acceptable. However, this is notnecessarily always the case for tworeasons.

Raw EFB consumption for a 10 MWebiomass power plant is in the order of upto 650 tonnes per day (24 hour plantoperation basis). Smaller mills may notbe able to generate enough waste EFB tomeet this daily requirement. Thus thewaste EFB may need to be imported from

Renewable Energy – The Need For FurtherIncentives ..................................................................................................................................................................................................................

By: Ir. Johan Alimin bin Samad, FIEM, P.Eng. C.Eng., FIChemE, MCFArb, ASEAN Eng., Int PE, APEC Eng.


F E A T U R E


other mills in the vicinity, incurringadditional transportation costs.

The transport cost added may beinsignificant however there are otherreasons not to assume that EFB isavailable at too low a cost. Recently EFBwaste has emerged as a possible valuableresource for other downstreamindustries. EFB waste can now be used tomake furniture products, fibre boardpanels, auto interiors, and biodegradablecontainers, to the extent that it is perhapsno longer a waste product but anemerging commodity. With theintroduction of other value added uses ofthe material, EFB may become a properlytraded commercial resource. Withoutproper introduction of market controlson the material, allowing its value to floatfreely according to market supply anddemand forces may result in pricefluctuations that can have pronouncedeconomic effects on an EFB biomasspower plant investment.

There is no standard price for EFBs,and so to protect an investment frombeing exposed too much to marketfluctuations in raw material price it isprudent to have in place long termarrangements for delivery of the materialat pre-determined prices as far aspossible. For a 10MWe EFB biomasspower plant requiring approximately200,000 tonnes per annum of EFB thisrequires considerable commitment froma raw EFB supplier.

Current EFB biomass power planteconomic models apparently assume thecost of EFB at between RM5–15 per tonneof raw EFB delivered to the consumer. As

the demand for EFB rises, and if supplyremains stagnant, then it is reasonable toassume the possibility of an inevitableincreasing trend in the price.

c) Plant O&M CostsPlant operation and maintenance (O&M)costs are predictable and are based onestablished power industry rates.Essentially the majority of the utilitiessection that make up an EFB biomasspower plant is similar to most thermalcycle power plants, with the exception ofperhaps the raw EFB moisture reductionprocess and ash handling (although thelatter is common also in coal powerplants.)

Moisture reduction processes are notuncommon. There are biomass powerplants in the USA, India and Europe thatalso deploy moisture reductiontechniques to lower moisture content inthe biomass feed stream to the boiler.However, palm oil EFB biomass is ratherunique to Malaysia and the knowledgebase for moisture reduction techniquesfor this material is largely home-grown.

The current moisture reductiontechnology deployed for EFB involves arather crude process of cutting thematerial to a smaller size and squeezingthe mass of cut pieces to drain it ofmoisture. The size reduction allows thesqueezing process to be more effectiveand the resultant treated biomass is in theform of fibre strands similar to coconuthusk.

The fibre form is also helpful forboiler combustion efficiency since thecombustible surface area of the materialis increased considerably.

Current technology providers for themoisture reduction process have spentconsiderable R&D efforts to successfullyaddress moisture and size reductiontargets for compatibility with commercialboilers, but the process itself is a largeelectrical consumer, taking up almost30% of the total biomass power plantauxiliary electrical load.

For a 10 MWe net capacity EFBbiomass power plant, the plant auxiliaryelectrical load approaches 2 MW,resulting in the need to build a plant withtotal gross capacity of 12 MWe, adding toplant investment cost.

Thus, more effort needs to be spent on further improving the moisture reduction technology on the energy demand side, to raiseefficiency in this section of the EFBBiomass power plant.

d) Electricity Sales PriceIt has been reported that TNB is willingto purchase electricity from EFB Biomasspower plants at around 17 sen/kWh in Peninsular Malaysia and 21 sen/kWhin Sabah and Sarawak. This puts EFB biomass power plants at the higher end of the cost scale whencompared with the more establishedfossil fuels.

It is however not evidently clear howthe price has been determined as thereare no mainstream market indicatorprices for raw EFB as opposed to coal,natural gas and diesel. Thus the questionremains as to whether it is a fair price or merely positioned by workingbackward from the end-consumer tariffcharge, minus delivery costs, to anaccommodated price.

e) Waste Streams ReutilisationThere are essentially two waste streamsfrom an EFB biomass power plant – oilywater and EFB ash.

The oily water comes from thesqueezing of the raw EFB in the moisturereduction stage, since apart from waterthe raw EFB contains residual palm oil.Based on EFB moisture reduction plantsalready in operation, the oil content inthe water is typically 8%.

A 600 tonne/day raw EFB moisturereduction plant, reducing moisture from65% to 50%, would generate 390tonne/day of oily water. At 8% oil inwater content there would be anequivalent of about 30 tonne/day of oil.Assuming the oil in water is only 80%recoverable, it would still yield a 24

F E A T U R E

tonne/day by-product stream ofunprocessed low grade palm oil that maystill be accepted by palm oil refineries.

Even if sold at a discounted priceover current CPO prices, the investmentcost of an oil recovery plant to reclaim thewaste oil can be justified and moreimportantly it provides an additionalrevenue stream for the power plant.

There is not enough published dataon the useful benefits of EFB ash,although it is postulated that there maybe further valuable uses similar to coalash and other biomass ash residues. Itcan otherwise be returned to the generalplantation environment as it is no moreharmful as is ash from the naturalburning of the palm oil tree and fruitbunch.

f) Project EconomicsTo stimulate growth in biomass powerplants the government further enhancedthe initial incentives for this sector. Thecurrent incentives as announced in the2004 Budget, allow a 100% allowance ontaxable gain for the first 10 years, and100% exemption on duty for importeditems meant for a biomass plant.

With these incentives, financialanalysis indicates that an IRR of 13.5%after tax is achievable (see Table 1),making an EFB biomass power plantonly marginally acceptable for a typicalinvestor. It should be noted, however,that the IRR model postulated is rathersimplified and does not take into accountthe cost for land, owner’s projectmanagement costs, and loan interest,thus making the overall investmentscenario, thereafter, much less attractive.

The main constraints in the financialmodel are the price of raw EFB and theelectricity sales tariff.

Assuming the electricity sales tariffremains at a maximum of 17 sen/kWhbut raw EFB costs increase by 50%, theIRR after tax reduces further to about10%, making project investment largelyunattractive.

Thus the uncertainty over the price ofEFB over the long term is a real cause forconcern and an easily evident factor thatcan hinder development of biomass EFBpower plants.

Considering that it is likely that rawEFB costs will rise over the long term,then the next constraint to success – theelectricity sales tariff – needs to beaddressed, and re-positioning the costprice above the current level needs to beexplored.

Proposed New Considerationsfor the Renewable EnergyPower Sector There are a number of factors, as follows,that perhaps now, more than ever, needto be considered to make the renewableenergy power sector a viable mainstay ofthe fifth fuel policy.

a) Review the limit for electricity sales from RE power generators

The current SREP programme onlyallows for up to 10 MW to be sold to thegrid from any one facility. As economiesof scale apply just as much to powerplants, the larger it is, and the moreelectricity it can sell, the better itseconomic viability tends to be.

As already mentioned previously the current limit also results in the need for perhaps too many plants than are necessary, or are even suitablefor the limited number of sitesgeographically that have viable access to a grid interconnection point, coupled with proximity to RE fuelsupply sources.

b) Establish cost benchmarks forbiomass fuel sources

Biomass fuels such as EFBs currently donot have an established pricing

mechanism or reliable benchmark. Asother uses emerge for each particularform of biomass, whether it is EFB, ricehusk or other forms of biomass, marketdemand and shrinking supply sourceswill force an increase in the base cost ofthe material.

In the long term a price escalation isprobably inevitable, however there aremore serious concerns that in the shortterm without control mechanisms, therewill be large opportunistic pricefluctuations.

c) Unbundle the cost of gridinterconnection

From the plant developer’s view,external infrastructure costs such astransmission lines should not have to beborne in full by the power plantdeveloper. The case for argument existsfrom the fact that the transmission linedistributor adds a wheeling charge to thecost of electricity which is finally paid bythe end consumer, thus the distributorshould also partake in some of theburden of cost for delivery.

A similarity exists with infrastructurecosts related to gas pipelines brought to anatural gas fired power plant. Powerplant developers in such case are onlyasked to pay a certain contribution to thefull cost of the infrastructure provided.

d) Review the electricity sales tariffat the interconnection point

The current level of 17 sen/kWh(Peninsular Malaysia), at which TNB iswilling to purchase electricity from a REpower developer should be reviewed.

Firstly, there are a number of differentRE sources or fuels. The tariff under theREPA needs to properly reflect the REsource or fuel, i.e. whether solar, hydro,wind, or biomass. Within the biomassclassification there will also be merits fordifferent tariff rate considerationsdepending on the type of biomass, i.e.EFB, rice husk, or other.

As has been mentioned earlier thereappears to be no evident basis on howthe current level of 17 sen/kWh forelectricity from an EFB biomass powerplant has been derived, especially whenthere is no established benchmark pricefor raw EFBs.

A re-evaluation of the tariff based on a detailed quantitative analysis(benchmarking EFB against all other fuels), and comprehensiveeconomic modeling, should provideproper justification and positioning of the tariff.


Figure 1 : Moisture laden Empty Fruit Bunches (EFBs)

Figure 2 : Processed EFB Fibres

F E A T U R E

e) Offer Green Energy as analternative for end-consumers

Malaysia has not yet offered GreenEnergy as an alternative tariff for end-consumers to opt for, despitelaunching Renewable Energy as ageneration source.

Green Energy is offered by a numberof countries now as an eco-friendlyalternative for consumers wishing to disassociate themselves withconventional fossil or nuclear fuels.Essentially consumers can elect topurchase Green Energy, which iselectricity specifically generated from RE sources. The tariff rates are slightly higher than conventional fuelsbut there are those fully committed to being environmentally conscious to make it a viable alternative to be offered.

With Green Energy available, there should also be a conscious effort to persuade conglomerates withlarge compound electricity bills toapportion some spending towards Green Energy, to support it and aid in its sustainability.

f) Further R&D initiativesThere is a need for further research on theuses of wastes generated from the use ofbiomass in power generation.

As mentioned earlier, there is littleknown published data on the possiblevaluable use of EFB ash. By contrast, ricehusk ash generated from rice huskbiomass power plants in Thailand is soldat a premium due to specific valuableproperties of the ash.

Further efforts are also needed to improve the efficiency of plant sub-systems, in particular improvingelectrical demand efficiency in the EFBmoisture reduction process.

CONCLUSIONFor Renewable Energy to remain as aviable fifth fuel in the electricity marketraw material resource base, moremeaningful and effective incentives needto be introduced.

Malaysia is not the only country thatwill most likely not meet its currenttarget for electricity generated fromRenewable Energy sources. The UK isalso set to announce a revised target anddeadline to provide greater incentive forinvestment in renewables [4].

EFBs remain as the most promisingRE source fuel for Malaysia but fairerelectricity sales tariffs, or betterincentives are required to ensurecommitment to investment in gridconnected EFB biomass power plants. n


Export Baseload (21 yrs) 10,000 kWPlant Availability 8,000 hrs/yrRaw EFB requirement (100% Load) 650 tonne/dayYear1 0 1 5 10 15 21

Investment (RM Thousands):Plant Capex 55,000

Revenue (RM Thousands):Electricity Sales 0.17 RM/kWh 13,600 13,600 13,600 13,600 13,600Total Revenue 13,600 13,600 13,600 13,600 13,600

O&M Costs (RM Thousands):Raw EFB 15 RM/tonne 3,250 3,250 3,250 3,250 3,250Labor, O&M Consumables & Spares 1,778 1,803 1,803 1,803 1,878Total Operating Costs 5,028 5,053 5,053 5,053 5,128Operating Profit/Loss (55,000) 8,572 8,547 8,547 8,547 8,472Applicable Tax 28% Tax2 – – – 2,393 2,372Profit/Loss after Tax (55,000) 8,572 8,547 8,547 6,154 6,100IRR before tax 14.7%IRR after tax 13.5%

Notes: 1. Intermediate years not shown2. Tax exemption – 100% of Taxable Gain for first 10 yrs.

Courtesy: Epitechnics Sdn Bhd

Table 1 : 10MWe EFB Biomass Power Plant IRR Analysis

REFERENCES

[1] “Energy – Industry Policies –Planting-up Programme inMalaysia, Forecasted ReserveMargin 2000 – 2005 ForMalaysia.” URL:http://www.ktkm.gov.my

[2] “Power industry to invest RM30bin next 5-10 years,” New StraitsTimes, July 24, 2003.

[3] “Tenaga Nasional Berhad AnnualReport 2003, President and ChiefExecutive Officer’s Review.” URL:http://www.tnb.com.my/tnb/ar2003/tnbar2003/NewFiles/mdreview.html

[4] “UK sets new renewables target,”The Chemical Engineer, February2004.

F E A T U R E


C O M M E N T

“To be or not to be” is the question ofthe day. Let me assure you that the

topic on one’s dilemma is not limited toengineers alone. It applies to many facets oflife. Well-renowned and famous authorshave written many books on the dilemmafaced by politicians and practitioners of themany professional disciplines. This isespecially true when one is at thecrossroads trying to find the right directionto go forward.

With this article, the writer would liketo share his two cents’ worth in response tothe request for a Real Engineer to stand upand wish to be counted. As the term, a“Real Engineer”, has not been clearlydefined, the writer declines to exposehimself to sarcastic criticisms by implyingto be a “Real Engineer” in the eyes of theengineering fraternity. The intention of thisarticle is to lighten the burden of self-skepticism on being a member of theengineering profession.

Many of us Homo sapiens, at one time orthe other, would have pondered on thequestions, “Why are we here?” and “Whatis our purpose in life?” People have chosentheir professional disciplines during theirstudent days. During their working life,some dreamed of achievements, some haveachieved something and some haveachievements thrust upon them. Thissounds familiar as the quotation is anadaptation from Shakespeare’s TwelfthNight.

So we must look at ourselves and askourselves, “What do we want in life?”Money though is important, is noteverything. One will find bliss if one iscontented and satisfied with what one haswhilst one will forever live in envy if one isinsatiable. Not every lawyer, accountant,engineer, or any other profession as amatter of fact, is a millionaire. Some will bevery rich and famous, some comfortable togo by and some will be still struggling tomake ends meet. It takes all sorts of peopleto make the world go round. With this thewriter hopes that this would have lightenedthe burden and anxiety of not being theleader of the rat race pack.

The writer hopes that the practicingengineers of today is one by his or her ownchoice and not of circumstances or forprestige’s sake. It must be the love of thesubject, in acquiring knowledge and

applying them in the course of our duty.This love should have eased the pain, tearsand sweat whilst going through the mill inbecoming an engineer.

With dedication and loyalty to theengineering profession, one would havedeveloped some sort of esprit de corpsamong other fellow engineers and eachwould lend a helping hand to one anotherin facing any acid test on the doubts of thereputation of an engineer. With thisunderstanding based on dedication andloyalty, members of different professionaldisciplines would form a congregation,organisation or institution to representthem in society. IEM is one suchorganisation representing the engineeringfraternity. How valuable IEM in socialstatus, commercial terms or in any otherway depends on its image and perceptionin the eyes of its members and the public atlarge. The image of IEM depends largely onits members. If the members themselves donot respect IEM as their one and onlyrepresentative, then their own bodylanguage would give themselves away,emanating negative vibes to anyone theycome in contact with. The attendantconsequence will be that the public at largewill not in turn show respect to IEM in duecourse. So IEM is what its members make itto be. Members should stand up and becounted in giving whatever contributionsrequired to make IEM a reputableorganisation in representing theengineering fraternity. Ask what you can dofor IEM and not what IEM can do for you.It is through voluntary support from itsmembers that IEM can function well andportray a respectable image. As the oldChinese saying goes, “Local ginger is notspicy,” the same image is being perceivedby the local public to a certain extent andIEM members themselves at large. Thewriter happened to be wearing an IEM tiewhile on assignment in conducting coursesoverseas. Some of the participants askedabout the IEM emblem on the tie. Theyshowed great respect when told that thewriter is a member of IEM which is aninstitution representing practicingengineers in Malaysia. So whether IEM hasany commercial value or not has to bedecided by each and everyone and by thepeople they come into contact with. Thewriter feels that it is the confidence one

shows in the line of duty that createswhatever value that could be attached to it.

Leadership is the next important issueat hand. Once a leader has been chosen, allmembers should close ranks and supportthe leader in promoting the image of IEM.Many voluntary organisations faces theproblem of always having armchair criticswho will give negative comments and findfault at every nook and corner. If they havebetter ideas, they should have offered theirservices to serve and contribute.Constructive criticisms are welcome as theyact as a check and balance for futureimprovement.

Legacy is a better reward for one’sactions instead of huge monetary gains. Thewriter has retired twice; the first time fromTenaga Nasional Berhad followed by a fouryear tenure with one of the IndependentPower Producers. During the said period,the writer did not become a multi-millionaire but felt contented and satisfiedin knowing that he has given his fullprofessional services answering the call ofduty in contributing towards the twocompanies’ performance. The legacy ofestablishing certain good systems of workpractices and gaining recognition amongpeers in having good working ethics andcompetency in knowledge sharing gives thewriter great satisfaction. This is especiallyso when one knows that during one’stenure, one’s services have contributedtowards the good performance as shown bymeasurable results. It is sad to know thatsome in management do not believe inproven legacy resulting in performancetaking a deflection southwards after a lapseof only one and a half years down the line.Anyway the people who are presently incontrol will have to face the music.

The writer hopes that this article willhelp fellow engineers banish negativethoughts when they have chosenengineering as their profession, eventhough one might not be driving a fancy carsuch as a Ferrari or own big bungalows bythe sea or in posh residential areas just yet.It is always better to look at the positiveside of everything. Who knows goodfortune may be smiling on you just aroundthe corner.

The writer hopes that engineerswhether they are in the top management orat the working level should showprofessionalism in their work especially inthe core values and ethics and in mentoringthe budding young ones to nurturesuccession towards a professionalengineering fraternity. Last and not least,the writer sincerely hopes that all engineerswould join IEM and contribute voluntarilyboth in effort and in kind towards makingIEM an institution that all engineers inMalaysia could be proud of. n

The Engineer’s Dilemma............................................................................................................

By: Ir. Mah Soo (F11102)


ANNOUNCEMENTISO ACHIEVEMENTS INENGINEERING

Dimension Publishing - the officialpublisher of the Institution of Engineers,Malaysia (IEM) - is proud to bring you theall-new ISO IN ENGINEERING publication.This special issue will be focusing on thecountry’s leading engineering companiesand organisations that have acquired theprestigious International Organisation forStandardisation (ISO) certifications foreither their respective services or products,or for both.

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WIDER COVERAGEBy being a part of ISO IN ENGINEERING,your products and services are not onlyreaching out to the readily-available targetaudience of highly-skilled professionalengineers who truly understands yourexpertise, but it also has a critical regionalpresence. More critically, we believe thatyou will stand to benefit from:• A circulation of over 15,000 professional

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2March 2004 was a big day for Ir. TohAh See, better known as A.S. Toh. On

that day, he received an MBR award fromour Prime Minister Dato’ Seri AbdullahAhmad Badawi.

MBR? It’s the Malaysia Book ofRecords. It may not carry the sameprestige as the Guinness Book ofRecords, but it’s not easy to get oneselflisted in it, except perhaps by attemptingto consume the greatest volume of tehtarik within a specific time or things likethat. Yet Ir. Toh has got, not one, but twolistings in the Book: for being the oldestto trek the Mt. Everest North Face, andfor doing the highest altitude trekking at5,807m above sea level.

Mountain trekking is in the blood ofIr. Toh. With his trademark gray hair, hehas the look of a wise philosopher, butunless you know him well, you won’t beable to imagine that within his slightbuild he has the will power and tenacityto conquer great heights that many atougher-looking guy may dread to tread.

Yet Ir. Toh is a late starter in mountaintrekking. He has a natural inclinationtowards outdoor activities andadventures, having close acquaintancewith the forest as a small boy. However,his busy schedule as a consultingengineer kept him away from his hobbiesuntil 1995 when he sold off his entirestake in Bina Runding Sdn. Bhd., theconsulting engineering company hefounded in 1971. Once freed of the hustleand bustle of business life, he began toindulge in all the things he had alwayswanted to do dearly, such as driving afunny looking white ball into a tiny hole(and they call it golf), and drinking toeach other’s health with a group offriends in a pub. Soon the 18 holes as wellas the 19th hole failed to give him enoughexcitement. He then picked up, first,scuba diving, and later, mountaintrekking. I happen to be one of hisregular diving buddies, though my urgefor the mountains is not as strong as his.

Since 1999, Ir. Toh has trekked Mt.Kinabalu in Sabah, Mt. Kilimanjaro inTanzania, part of the Annapurna circuitin Nepal, the north face of Mt. Everest in

Tibet, the Aconcagua BaseCamp in Argentina, and thegreat steppes of Mongolia.

I first got to know Ir. Tohalmost 30 years ago when Iwas working in JKR in JohorBaru. I got to know him betterwhen I joined Pre-StressedConcrete (Malaysia) Sdn.Bhd. in 1978 after completingmy term of contract in JKR.However, it was after hisretirement and my discoverythat we had some commoninterests that we really got toknow each other well.

Born in Muar in 1939, Ir.Toh received his earlyeducation in Chung HwaPrimary School and St.Andrew Secondary School in Muar. Hedid his Sixth Form in St. John’sInstitution in Kuala Lumpur. Hegraduated with a civil engineeringdegree from the University of Malaya in1965.

After spending one year with aprivate firm, Ir. Toh joined JKR in 1966.He left JKR in 1971 to start his ownbusiness. He was so enterprising that hein fact started two businesses at the sametime: Bina Runding Sdn. Bhd. and Pre-Stressed Concrete (M) Sdn. Bhd. He wasactually a pioneer as one of the firstengineers in the country to have one legin consultancy and the other inconstruction. But true to his character, heavoided any conflict of interest in all hisdealings in both areas. The rest, as theysay, is history.

Ir. Toh has other interests as well. Helikes to travel and is a keenphotographer. These two hobbies gotogether very well and he takes a lot ofpictures when he travels. He has alsotaken up underwater photography tocapture images of the enchantingdenizens of the coral reefs.

Ir. Toh writes well. He does not writetravel stories only but on issues of publicinterest as well. Most of his writings werepublished in local dailies.

He has established a personalwebsite, www.nakedeyeview.com.my, tokeep his writings and photographs in aplace that is easily accessible not only tohimself but to his friends and anyonewho may be interested.

There is a soft spot in Ir. Toh’s heart.He cannot stand mother nature and ourliving environment being abused bymindless beings. He cannot even standthe sight of beasts such as camels andhorses being subject to unduly heavyburden. He considers this as a form oftorture.

Scaling Greater Heights After Retirement...................................................................................................................................................................................

By: Ir. Chin Mee Poon, Standing Committee on Publications

Ir. Toh receiving an MBR award from the PM

Ir. Toh at Camp 2, Mt. Everest North Face, Tibet

F E A T U R E


Ir. Toh and his beloved wife Lucyhave two children. Son Wei Ming is anelectrical & electronic engineer. He ismarried to Selina Yong, an accountant. SuMei the daughter is more like the father.She is such a staunch environmentalistthat she refuses to drive in order not topollute the air.

At the age of 65, Ir. Toh has manyplans. He wants to take up ice climbing.He is planning to climb Mt. Rainier inWashington State in the USA to brush upthe skill. After that he will climb amountain in Antarctica. His goal is toclimb in every continent. He also plans toorganise a trekking event to raise fundsfor charities.

Ir. Toh likes to see more young people taking up mountain trekking. He believes the sport not only bringspeople closer to nature to enjoy crisp air, the pristine environment andspectacular views, it also strengthensone’s willpower and rewards trekkerswith the most profound sense of achievement and satisfaction uponovercoming the challenges in scalinggreater heights. nIr. Toh trekking on ice in Mt. Aconcagua

F E A T U R E

Documents

CONTENTS · By : Ir. Prof. Abang Abdullah bin Abang Ali, IEM President PRESIDENT’S CORNER CALL FOR CONTRIBUTIONS To all Members and Readers, The Editorial Board is planning for