Tall Building MKA Jan 2011

BLD 510 Construction Technology III BSc (Hons) Construction Management

Mals MKays 1Building Department, UiTM

BLD 510 Construction Technology III

Prepared and Presented By:

MUHAMMAD KAMAL AHMADBuilding Department

Faculty of Architecture, Planning and

Surveying

University of Technology MARA

TALL TALL BUILDINGSBUILDINGS

CONTENTS1.0 INTRODUCTION2.0 EVOLUTION OF TALL BUILDING3.0 WORLD TALLEST BUILDING4.0 PLANNING CONSIDERATION5.0 DESIGN FACTORS 6.0 LOAD ACTION ON TALL BUILDING7.0 TALL BUILDING STRUCTURAL SYSTEM8.0 VERTICAL LOADING SYSTEMS9.0 HORIZONTAL LOADING SYSTEMS10.0 FLOOR SYSTEM FOR TALL BUILDING11.0 WALLS SYSTEM FOR TALL BUILDING12.0 FOUNDATION SYSTEM FOR TALL BUILDING13.0 CONSTRUCTION ASPECT OF TALL BUILDING14.0 SAFETY SYSTEM FOR TALL BUILDING



1.0 INTRODUCTION1.0 INTRODUCTION1.0 INTRODUCTION1.0 INTRODUCTION� The term ‘tall buildings’ is not defined in specific term

related to height or the number of storeys. A building isconsidered tall when its structural analysis and designare in some way affected by the lateral loads,particularly sway caused by such loads.

� According to Emporis Standards Committee (ESC) TallBuilding is defined as a building 35 meters or greater inheight, which is divided at regular intervals intooccupiable levels. To be considered a high-rise buildinga structure must be based on solid ground, andfabricated along its full height through deliberateprocesses (as opposed to naturally-occurringformations).

� According to the regulations of Danish, German andsome other European countries, the 72ft. (21.6m = 8stories buildings), having fire-fighting equipment, areknown as tall buildings.

� Definitions represented by the U.S. Council on tallbuildings and urban settlement refers to tall buildingsas these in which the height, influences the planning,construction and spaces application aspects of thebuilding considerably without specifying the number ofstories.

1.1 REASON FOR USING TALL BUILDING1.1 REASON FOR USING TALL BUILDING1.1 REASON FOR USING TALL BUILDING1.1 REASON FOR USING TALL BUILDING

SPACE LIMITATION PRESTIGE

• the process urbanmigration

• increase in thepopulation density of cities

• increasing land pricesmake it necessary tomaximise space utilisationby building upwards.

• free imposing advertisementsfor their owners and even thecity it is sited.

• as a show of political oreconomic power

• dominate the landscape andeasily become landmarks

•human ego and competition



2.02.02.02.0 EVOLUTION OF TALL BUILDINGEVOLUTION OF TALL BUILDINGEVOLUTION OF TALL BUILDINGEVOLUTION OF TALL BUILDING

Masonry wall bearing structures with thick and messy walls.

The horizontal and lateral loads of these structures were mainly

Resisted solely by the load bearing masonry walls.

Steel structures and sophisticated services such as mechanical lifts

and ventilation, limitations on the height of buildings were removed.

Reinforced concrete established. Architectural emphasis on

reasons, functional and technological facts. Transition of structural

systems from rigid frame to more efficient structural systems

1

2

3

Reliance Building

Chicago, 1894

Guaranty Building,

Buffalo, 1895.

Carson Pirie Scott

Department Store,

Chicago, 1904

The First Evolution of Tall BuildingsThe First Evolution of Tall BuildingsThe First Evolution of Tall BuildingsThe First Evolution of Tall Buildings



Woolworth Building,

New York, 1930

Chrysler Building,

New York, 1930

Empire State Building,

New York, 1931 (highest

structure in 19th

century)

The Second Evolution of Tall BuildingsThe Second Evolution of Tall BuildingsThe Second Evolution of Tall BuildingsThe Second Evolution of Tall Buildings

World Trade Centre,

New York, 1972

Sears Tower,

Chicago, 1974

Petronas Twin Tower,

Kuala Lumpur, 1996.

The Third Evolution of Tall BuildingsThe Third Evolution of Tall BuildingsThe Third Evolution of Tall BuildingsThe Third Evolution of Tall Buildings



3.0 WORLD TALLEST BUILDINGS3.0 WORLD TALLEST BUILDINGS3.0 WORLD TALLEST BUILDINGS3.0 WORLD TALLEST BUILDINGS

* * *



List of World Tallest BuildingsList of World Tallest BuildingsList of World Tallest BuildingsList of World Tallest Buildings

� Refer to Appendix 1.

� Refer to Appendix 2

4.0 PLANNING CONSIDERATIONS4.0 PLANNING CONSIDERATIONS4.0 PLANNING CONSIDERATIONS4.0 PLANNING CONSIDERATIONS� The selection of a tall building structure isnot based merely on understanding thestructure in its own context.

� The selection may be more function offactors related to cultural, social,economical and technological needs.

� Some of the factors:a. General Economic Considerationsb. Soil Conditionc. Height to width Ratio of a Buildingd. Fabrication and Erection Consideratione. Mechanical Systems Considerationsf. Fire Rating Considerationsg. Local Considerationsh. Availability and Cost of Main

Construction Materials



a. General Economic Considerationsa. General Economic Considerationsa. General Economic Considerationsa. General Economic Considerations� How much the projects costs to build.� How much the finished project costs to operate (e.g.expenses associated with utilities, maintenance, insurance,taxes, interest on borrowed money)

� As the height of the building increases, more and more spaceis needed for structure, mechanical systems and elevators,leaving less rental space.

� The costs of elevators and mechanical systems increase withheight.

� Cost for sophisticated construction equipment as building gettaller.

b. Soil Conditionb. Soil Conditionb. Soil Conditionb. Soil Condition� The performance of a building is dependent on thestrength of the soil which it is founded.

� The foundation or substructure binds the superstructure tothe soil.

� If the bearing capacity of the soil is rather low, piles orcaissons may be required to reach the proper foundationsupport.



c. Height c. Height c. Height c. Height ––––totototo---- Width Ratio of BuildingWidth Ratio of BuildingWidth Ratio of BuildingWidth Ratio of Building

� As the minimum height-to-width ratio increases, soshould the building’sinherent stiffness

� The stiffness of the buildingstructure is dependent onsize and number of bays,structural systems andrigidity of members andconnections.

� The general height-to-widthfor a plane frame structurein the range of 5 to 7.

d. Fabrication and Erection Considerationsd. Fabrication and Erection Considerationsd. Fabrication and Erection Considerationsd. Fabrication and Erection Considerations

� The planning of fabrication anderection procedures may indicateimportant factors concerningstructural systems selection.

� Should be a minimum number ofstructural pieces to shortenconstruction time, complicatedclosed form shapes should beavoided and field welding should beminimized.



e. Mechanical Systems Considerations

� Average more than one-third of total tall building costs.

� Effects on the building overall appearance and economic selection of a structural systems.

f. Fire Rating Considerationsf. Fire Rating Considerationsf. Fire Rating Considerationsf. Fire Rating Considerations

� Almost all floors are beyond thereach of fire truck ladders, firefighting and rescue action are fromthe inside of a building.

� Total emergency evacuation isimpossible within a reasonably shortperiod of time.

� Must be able to ensure the following:* structural integrity for a certain

period of time.* confinement of the fire, to

prevent it from spreading tocertain building areas.

* adequate exit systems.* effective smoke and fire

detection systems.* sprinklers and necessary smoke

and heat venting.



g. Local Considerationsg. Local Considerationsg. Local Considerationsg. Local Considerations

� For example, height limitation, zoning regulations.

h. Availability and Cost of Main h. Availability and Cost of Main h. Availability and Cost of Main h. Availability and Cost of Main

Construction MaterialsConstruction MaterialsConstruction MaterialsConstruction Materials

� If a desired material is hard to acquire, it may delay the building schedule and add significantly to building costs.



DESIGN AND CONSTRUCTION

CONSIDERATION

Mobility

Materials

Heat

SpeedWind

Earthquakes

Evacuatian

5.0 DESIGN5.0 DESIGN5.0 DESIGN5.0 DESIGN

TOTAL DESIGN APPROACH

requires a team approach between

the various disciplinesof design, material

fabricationand building construction

building mustcope with verticalforces of gravityand horizontalforces of windabove grund andthe seismic forcesbelow ground

building envelope hasto accommodate thedifferences intemperature, airpressure andhumidity betweenexterior and interiorenvironments

the structural elements of the building must responds to allthis forces where members must be arranged andconnected to one another in such manner as to absorb theforces and guide them safely with a minimum effort to theground.



Design ParametersDesign ParametersDesign ParametersDesign Parameters

Design Process and ToolsDesign Process and ToolsDesign Process and ToolsDesign Process and Tools



Design Elements of Tall Building FormDesign Elements of Tall Building FormDesign Elements of Tall Building FormDesign Elements of Tall Building Form

6.0 LOAD ACTION ON TALL BUILDINGS6.0 LOAD ACTION ON TALL BUILDINGS6.0 LOAD ACTION ON TALL BUILDINGS6.0 LOAD ACTION ON TALL BUILDINGS

� Dead Loads� Live Loads� Wind Loads� Seismic Loading� Construction Loads� Loads Due to Restrained Volume Changes of Materials

� Rain, Snow & Ice Loads� Water and Earth Pressure Loads� Impact and Dynamic Loads� Blast Loads� Combination of Loads



a. Dead Loada. Dead Loada. Dead Loada. Dead Load

� Static forces caused by theweight of every elementwithin the structure.

� The forces resulting in deadload consists of the weightsof the load bearing elementsof the building, floor andceiling finishes, permanentpartition walls, façadecladding, storage tanks,mechanical distributionsystems etc.

b. Live Loadb. Live Loadb. Live Loadb. Live Load� ‘Occupancy Loads’ : Loadscaused by the contents ofobjects within or on abuilding. Not part of thestructure

� Include weights of people,furniture, movablepartitions, mechanicalequipments (e.gcomputers, businessmachines) etc.

� Variable andunpredictable. Change inlive loads not only overtime but also as a functionof location.



c. Wind Loadsc. Wind Loadsc. Wind Loadsc. Wind Loads� Lateral action caused bywinds.

� Wind velocity in generalincreases with height. Thetaller the building is, themore exposed the building tostrong winds.

� Can cause the parts of theexternal wall or roof to beblown off.

� If the building is slender, itwill sway or vibrate in thewind.

� Major problem for thedesigner of tall buildings.

d. Seismic Loadingd. Seismic Loadingd. Seismic Loadingd. Seismic Loading

� The earth’s crust is notstatic; its subject toconstant motion.

� Seismic motion acts onthe building by shakingthe foundation back andforth.

� The mass of the buildingresists this motion,setting up inertia forcesthroughout the structure



e. Construction Loadse. Construction Loadse. Construction Loadse. Construction Loads

� Loads during constructionof a building – examplecontractors commonlystockpile heavyequipment and materialson a small area of thestructure.

� Causes concentratedloads that are muchlarger than the assumedlive loads which thestructure was designed.

7.0 TALL BUILDING STRUCTURAL SYSTEMS7.0 TALL BUILDING STRUCTURAL SYSTEMS7.0 TALL BUILDING STRUCTURAL SYSTEMS7.0 TALL BUILDING STRUCTURAL SYSTEMS

Linear

Elements

Surface

Elements

Spatia

Elements

- Column and Beam- Capable of resistingaxial and rotationalbeam

- Wall : either solid withpeforation or trussed,capable of carrying axial and rotationalforces

- Façade envelope or core for example, tying the building together to act as aunit

- Floor : solid or ribbed,supported on floorframing, capable of supporting forces in and perpendicular to the plane



- types of structural systems

� Parallel Bearing Walls

� Cores and Façade Bearing Walls

� Self Supporting Boxes

� Cantilevered Slab

� Flat Slab

� Interspatial

� Suspension

� Staggered Truss

� Rigid Frame

� Rigid Frame and Core

� Trussed Frame

� Belt-Trussed and Core

� Tube in Tube

� Bundled Tube

a. Parallel Bearing Walls

� Comprised of plannarvertical elements that areprestressed by their ownweight, thus efficientlyabsorb lateral forceaction.

� Used mostly forapartment building aherelarge free spaces are notneeded and mechanicalsystems do notnecessitate corestructures.



b. Cores and Facades Bearing Walls

� Planar vertical elementsform exterior wallsaround a core structure.

� This allows for openinterior spaces, whichdepend on the spanningcapacities of the floorstructure.

� The core housesmechanical and verticaltransportation systemsand adds to the stiffenesof the building

c. Rigid Frame� Rigid joints are used betweenan assemblage of linearelements to form vertical andhorizontal planes.

� The vertical planes consistsof columns and girdersmostly on a rectangular grid

� A similar organizational gridis used is used for thehorizontal planes consistingof beams and girders.

� With the integrity of thespatial skeleton depending onthe strength and rigidity ofthe individual columns andbeams, story height andcolumn spacing becomecontrolling designconsiderations



d. Rigid Frame and Core

� As rigid frame butintroducing a corestructure to increasethe lateral resistanceof the building as aresult of the core andframe interaction.

� The core systemshouse the mechanicaland verticaltransportationsystems.

e. Self Supporting Boxes

� Boxes are prefabricatedthree dimensional unitsthat resemble thebearing wall when theyare place and joinedtogether.

� The boxes are stackedlike bricks in the’English pattern bond’resulting in a crisscrossed wall beamsystem.



f. Cantilevered Slab

� Supporting the floorsystems from a centralcore allown for acolumn-free space withthe strength of the slabas the limit of thebuilding size.

� Large quantities of steelare required especiallywith large slabprojections.

� Slab stiffenes can beincreased by tackingadvantage ofprestressing techniques.

g. Flat Slab

� Generally consists ofuniformly thickconcrete floor slabssupported oncolumns

� No deep beamsallowing for amimimum storyheight



h. Interspatial

� Cantilevered story highframed structures areemployed on everyother floor to createusable space withinand above the frame.

� The space within theframed floor is used forfixed operations, andthe totally free spaceabove the frame canadapt to any type ofactivity.

i. Suspension

� Employing hangers instead of columns to carry the floor loads.

� The cables carry the gravity loads to trusses cantilevering from a central core.



j. Staggered Truss

� Story-high trusses arearranged so that eachbuilding floor restsalternatively on thetop chord of one trussand the bottom of thenext.

� Besides carrying thevertical loads, thistruss arrangementminimizes windbracing requirementsby transferring windloads to the basethrough web membersand floor slab.

k. Trussed Frame� Combining a rigid (orhinged) frame withvertical shear trussesprovides an increase instrength and stiffenesof the structure.

� The design of thestructure may bebased on using theframe for theresistance of gravityloads and the verticaltruss for wind loadssimilar to the riogidframe and core case.



l. Belt Trussed Frame and Core

� Belt trusses tie the façade columns to the core, thus eliminating the individual action of frame and core.

� The bracing is called cap trussing when it is on the top of the building and belt trussing when around lower sections.

m. Tube in Tube� The exterior columnsand beams are spacedso closely that thefaçade has theappearance of a wallwith perforated windowopenings.

� The entire building actsas a hollow tubecantilevering out of theground.

� The interior core (tube)increases the stiffenesof the building bysharing the loads withthe facade tube.



n. Bundled Tube

� An assemblage ofindividual tubesresulting in amultiple-cell tube.

� The increase instiffnes is apparentand allows for thegreates height andthe most floor area.

STRUCTURAL SYSTEMS FOR TALL BUILDINGS OF DIFFERENT HEIGHTS





Efficiency of structural systems of tall buildings

Building Cases Year Stories Slender kN/m2 Structural

Empire State Building, New York 1931 102 9.3 2.02 Braced rigid frame

John Hancock Centre, Chicago 1968 100 7.9 1.42 Trussed tube

World Trade Centre, New York 1972 110 6.9 1.77 Frame tube

Sears Tower, Chicago 1974 109 6.4 1.58 Bundled tube

Chase Manhattan, New York 1963 60 7.3 2.64 Braced rigid frame

US Steel Building, Pittsburgh 1971 64 6.3 1.44 Shearwalls+outrigger+belt trusses

IDS Centre, Minneapolis 1971 57 6.1 0.86 Shearwalls+outrigger+belt trusses

Boston Co. Building, Boston 1970 41 4.1 1.01 K-braced tube

Alcoa Building, San Francisco 1969 26 4.0 1.24 Latticed tube

U.S Steel TowerJohn Hancock Centre

Empire State Building

Alcoa Building, San

Francisco

Boston Co. Building,

Boston

8.0 VERTICAL LOADING SYSTEMS OF TALL BUILDINGSVERTICAL LOADING SYSTEMS OF TALL BUILDINGSVERTICAL LOADING SYSTEMS OF TALL BUILDINGSVERTICAL LOADING SYSTEMS OF TALL BUILDINGS

� The main function of the verticalloading systems is to transfer the deadand live loads of the superstructure tothe substructure.

� Systems of transferring the loads:

- Structural Wall System

- Skeleton frame System

- Suspension System

- Composite Wall Frame System

- Cantilevered Floor System

- Transfers System



a. Structural Wall System� Loads are transmitted to the ground via floor and

wall (designed as load bearing wall).� Masonry and brick load bearing were common

during the late 19th and late 20th century.� Now load bearing walls are made from reinforced

concrete ;high performance concrete (HPC) .� Usually of precast concrete panels systems and

cast in situ concrete buildings using ‘tunnel forms’.� Usually residential type because the internal wall

layout do not need to be changeable such as inoffice building.

b. Skeleton Frame System

� Loads are transferred to thebeam and column grid to theground.

� Using RC or Steel frame.

� Faster to erect especiallywhen structural steel is used



c. Suspension System

� The floors of thebuilding aresuspended over a longspan.

� Ability to provide acolumn free floor.

� Three types:

i. Hanger system

ii. Bridge System

iii. Catenary System

i. Hanger System� Loads are transmittedupwards through verticaltensile members to outriggerarms.

� The loads are thentransferred from theoutriggers to one or morepiers that transmit the loadsto the ground.

� The tensile members can behangers or cables and thepier tower are eithermonolithic reinforcedconcrete load bearing wallsor steel framed tower.

� e.g Sabah FoundationBuilding ; Hong Kong &Shanghai Bank Building,Hongkong.

Central Pier Tower

Curtain Wall Facade

Hanger Elements

Tension Ring

Sabah Foundation Building Structural System



Hongkong & Shanghai Bank Building, Hong Kong

ii. Bridge System

� The floor slabs aresuspended between two ormore towers or megacolumns.

� No intermediate columnsused to support the floorslabs.

� e.g ; Tabung Haji Building,Petronas Twin Towers,OCBC Singapore.

Knights of Columbus Building

Corner core RC tower ; contains either stairs or risers and toilets

Floor slab structural girder and beams

Central core RC tower; contains lifts shafts

Tabung Haji BuildingOCBC Singapore



iii. Cantenary System

� Example: FederalReserve bank ofMinneapolis

� Consisted of a pair ofcatenary membersthat span betweentwo towers.

� Both catenarymembers lie on thelong facades of thebuilding



d. Composite Wall-Frame System� The skeleton frame and structural load

bearing walls are used together.� Several arrangements:

i. - the wall are arranged to form a core.- the frame surrounds the core walls.- tubes configuration.

ii.- the walls are located at opposite ends of square shaped plan; generally C-shaped.- the frame is located between the endwalls.

iii.- the walls are located at the corners ofsquare shaped or rectangular shapedplan.- the corner walls are L-shaped.- the frame is located within the planand four corner walls.



e. Cantilevered Floor System� Floor slabs rest on beams cantilevering

from a central tower.� The loads of the building is transferred

to the foundation through the centraltower.

� E.g: Nagakin Capsule Tower, MarinaBuilding, Miami & Turnig Torso Malmo





f. Transfer System

� For building where lower floorshave lesser columns than therest of the building.

� The transfer is in the form of ahorizontal elements.

� Consists of mega column andmega beams at lower floor

� Skeleton frame is positionedabove the transfer megastructures.

� The loads are transferred fromthe transfer mega beams to themega columns and then to thefoundation.

8.1 Minimizing Vertical Loads8.1 Minimizing Vertical Loads8.1 Minimizing Vertical Loads8.1 Minimizing Vertical Loads� Foundations costs may be lower if the total vertical loads can be reduced

� Some of the ways are:

- reducing the floor plan area as the building increases

- using lighter materials in the upper floors

- using steel instead of R.C for the structural system

- reducing the cross-section area of the structural members in the upper floors

- placing the heavier M&E plant in an adjunct building e.g using district cooling system.



9.0 HORIZONTAL LOADING SYSTEM9.0 HORIZONTAL LOADING SYSTEM9.0 HORIZONTAL LOADING SYSTEM9.0 HORIZONTAL LOADING SYSTEM

� Horizontal (lateral)forces act on thesuperstructure andsubstructure ofbuildings.

� Two types ofhorizontal forces:

i. Wind Forces

ii. Earthquake Forces

WIND FORCES

� Wind is variable both indirection and strength.

� Wind exerts loads on thetall structure causing it tooscillate or sway like apendulum.

� Oscillations must be keptto a minimum:- to ensure occupants’

psychological andphysical comfort.

- to preventdeterioration of jointsin the curtain wallingand building services.

� Earthquakes create lateralforces on a tall buildingcausing it to sway.

� Cause the ground tomove horizontally andvertically

� Earthquake-resistantbuilding has to absorb orcounteract the forces.

EARTHQUAKES



9.1 Preventing Oscillation of Tall Building

Three main ways:

1. Structural methods by eitherstiffening or having heaviermass.- Shear Walls- Moment Resistant Frame

Systems : eg tubesystems

- Bracing- Diagrid systems

2. Counteracting the oscillationby either damping devices ortop-to-bottom structural tiemembers.- Guying methods- Damping Devices :

Passive dampers orActive dampers

3. Aerodynamic methods.

a. Structural Methodsi. Shear Walls

� Structural elements to inducestiffenes in the building.

� Monolithic walls of reinforcedconcrete, brick or masonrycan be used to providestiffenes ; walls with amoment resistant frame.

� Location of the shear wallsare:

- Central core of building

- Ends or corners ofbuilding

- At certain wall positioninside the building



a. Structural Methodsii. Moment Resistant Frame

Systems (also known asSkeleton Frame)

� Three dimensional grid oflinear column and beams –connected each other usingrigid or semi rigidconnections.

� Usually used ‘tubes systems’– load bearing columns ofthe exterior perimeterare placed togetherto form a ‘tube’.

- single tube ; tube withintube; bundling oftubes; braced tubes

� e.g : Xerox Building USA,Sears Towers USA





a. Structural Methodsiii. Bracing� Adding braces to the frame.� The bracing can be in different locations in

the structure.� The bracing configurations includes:

- some vertical and/or horizontal bays of the frame are braced.

- solid beam bracing- used to brace shear walls together.

- vertical truss – consists of mega column, mega beam and mega brace single plane truss arrangement that is located along the height of the moment resistant frame.

- a mega space truss that housed floor slabs, minor columns and beams.

� E.g: Bank of China, Hong Kong, John Hancock Building, USA, Hong Kong Shanghai bank, Hong Kong







a. Structural Methodsiv. Diagrid Systems

� Consists of a grid of diagonal members that cross each other.

� The distrubution of the load is similar to that experienced in a single layer grid dome.

� The diagrid is tied to the core by the floor elements along the height of the building.

� At the top of the building the diagrid terminates to either a ring beam or the core itself.

� Hearst Tower ; Swiss Re Building, London; Hubbell Lighting Headquarters -Greenville, S.C



b. Counteracting The Oscillationi. Guying Method� Top-to-bottom

structural tie membersare installed to the mainvertical structure toprevent swaying of thestructure.

� The structural tiemembers are eithersteel cables that arestretched or monolithicR.C Fins that areextended between theground and the top ofthe tall buildings.

� Usually used for towers.

b. Counteracting The Oscillationii. Damping Services� The devices are used in the structure of lighter tall

buildings (normally of steel frame construction) and tall‘pencil’ thin towers and spires of super tall buildings.

� Several types of dampers”* Passive Dampers : is tuned to react to the movementof the building- viscoelastic dampers- passive tuned mass dampers- pendulum tuned mass dampers- liquid tuned mass dampers- viscous liquid dampers

* Active Dampers : require sensors to detect themovement and initiate the mechanical hydraulic pistonactuators that push against the damper mass andstructure.



Passive Dampersi. Viscoelastic Dampers� Viscoelastic material isplaced at various pointsin the structure ; oftena rubber or neoprenepad sandwichedbetween the faces oftwo steel members.

� The pad provide shearresistance to theoscillations forces.

� Eg. Former WorldTrade Centre NewYork.

ii. Passive Tuned Mass Dampers� These are sliding or horizontal

moving mass of steel or concretetuned to move in reaction to thehorizontal movement of thebuilding.

� The slab lies on a bed of oil andheld in position by heavy springs(or hydraulic pistons) attached tothe structural frame of thebuilding.

� The movement of the buildingcauses the mass to compresssome spring and extend theothers.

� The extended springs pulls on thebuilding frame while thecompressed springs pushes onthe time.

� This counteracts the movementof the building

� Usually located at top of buildingwhere the swing of the oscillationis most.

Passive Dampers



iii.Pendulum Tuned Mass Dampers� A suspended mass acting as pendulum is used.� The pendulum mass is held by pistons.� Act similar to the passive tuned mass damper.� Need high head room� E.g : Taipei 101 building.

Passive Dampers

iv.Liquid Tuned MassDampers

� Consists of two largetanks or more whosewater contents flow fromtank to tank in responseto lateral forces thatsway the building.

� The sloshing forces of thewater on the sides of thetanks as it moves fromone tank to anothercounteract the swayingforces.

� Water tank forfirefighting or airconditioning system ofthe building can be usedfor this purpose.

Passive Dampers



v. Viscous Liquid Dampers.

� Similar to the use ofhydraulic pistons incars to absorbvibrations from theroad.

� Special hydraulicpistons containsviscous liquid areplaced at suitablelocations throughoutthe buildings.

� E.g: Torre MayorBuilding, Mexico City

Passive Dampers

Active Dampers� Require sensors to detect the movement and initiate themechanical hydraulic piston actuators that push againstthe damper mass and structure.

� Require external mechanisms and electricity to move them inresponse to the horizontal movement of the building.

� Computers are used to fine tune the responses to the swayingof the building.



Hybrid Damper� Passive active damper that have both the passive damper and active

damper� The passive damper is used to for the initial movement up to a dynamic

movement point where it turns off and the active damper activates torespond to the movement.

� Now used as an earthquake measure rather than resist wind inducedoscillation.

� E.g: Fukuoka Building, Japan.

c. Aerodynamics Methods� The building cross sectional plan is

designed to have minimum airturbulence that could causeoscillation.

� The reduction or air turbulence canbe obtained by:i. have circular plan rather

than rectangular or squareplan of the building.

ii cutting or rounding off thecorners of the building.

iii. Providing for perforation atthe corners of the building orin the building.

iv. Having channels in thebuildings silhouette thatallow the wind to bechanneled away from theface of the building

� e.g: Shanghai World FinancialCentre

1 2 3 4 5



10.0 FLOOR SYSTEM FOR TALL BUILDING10.0 FLOOR SYSTEM FOR TALL BUILDING10.0 FLOOR SYSTEM FOR TALL BUILDING10.0 FLOOR SYSTEM FOR TALL BUILDING� Tall buildings has many floors.� Have to fulfill several functions – bearing of loads, fire resistance, sound insulation, heat insulation and aesthetics.

� Divided to three parts:- floor structural- floor finish- ceiling (soffit of floor) finish



10.1 Floor Structural System

� Parts of the building that contribute to the structural stability of the building.

Two structural functions:

Vertical Loading Function Horizontal Loading Function

•To carry the live loads and deadloads .

•Has to transfer loads to eithersupport beams of the structuralframe or supporting structural walls.

•Must stiff enough as to neithernoticeably deflect due to the loadnor felt to oscillate when repetitiveimpact loads are applied.

•To act as internal ‘struts’ of thebuilding’s horizontal loadingstructural systems.

•Depth of the slab and its supportingjoists/girders influences the degreeof stiffness of the overall building;but more materials and increasesthe loads exerted on the foundation– foundation costs will increased

Dilemma to the designer ; use of lighter materials (steel or lightweight reinforced concrete, using trusses and creating cavities in the structure ) to reduce loads and costs but building tend to sway in the wind.

Types of Floor Structures:

LIGHT WEIGHT OR NORMAL CONCRETE FLOOR STRUCTURES

-the main and structural materialis reinforced concrete

-the floor plate is supported by r.cjoists that span between theperimeter beams of the floor bay.

-generally use cast-in-situconcrete floors but sometimesprecast concrete is used for thefloors.

-if have long spans withoutintermediate supporting columns,prestressed concrete slabs oreither prestressed concrete jointsare used.



Types of Floor Structures:

COMPOSITE FLOOR STRUCTURES

-

- combination of steel and concrete- may be one of the following:* cast in situ concrete slab oncorrugated metal deck.

* precast concrete planks on beams* steel joists embedded in concrete



10.2 Floor Finishes

� Screed Floor– usually cement screed

which is laid on theconcrete slab.

- tiling or membrane typecovers are laid on thescreed.

- access boxes for the m &Educts laid in the floor slabare positioned relevantto the layout of the floor.

� Raised Floor- proprietary raised floor are

installed onto the floorcreating a false floor.

- space within the raised flooraccommodate M & E ducts,cables etc and allows theuse of under floor airconditioning plenums.

10.3 Ceiling Finishes� Wet Construction

- either plastered or sprayfinished or cemented acoustictiling that are clad directly tothe floor soffit.

- usually for residential building.

� Dry Construction- dry boards or tiles fastened on

a frame either suspendedfrom the floor soffit or fixeddirectly to the floor soffit.

- dry boards are made fromgypsum, wood cement etc

- ceiling are either attacheddirectly to the floor orsuspended with hanging wiresor rods from the floors.



� Walls enclose space and serves thefunctions of weather exclusion, thermaland sound insulation.

� It also provides adequate strength,stability, durability, fire resistanceaesthetic appeal, etc.

11.0 WALL SYSTEM FOR TALL BUILDING11.0 WALL SYSTEM FOR TALL BUILDING11.0 WALL SYSTEM FOR TALL BUILDING11.0 WALL SYSTEM FOR TALL BUILDING

11.1 Factors of External Walls System

� Visual- panel, shape and size- joint locations, joint sizes- daylighting, nightlighting- blinds, shades- materials, colours, finishes- integration with interior design, e.g

cabling behind partitions.� Integrity

- air and water tightness ; sealing,drainage, indoor air quality

- loading; static, dynamic, fatigue- movements ; loads, thermal,

moisture- exceptional loads; blast, intrusion,

impact- fire ; resistance, reaction, spread

verticality and horizontally



� Physics/Environment/Comfort- heat transfer- lighting- sound transmission ; noise from street,

next room- ventilation- moisture ; rainwater, humidity,

condensation, degradation, mouldgrowth.

� Buildability- tolerance- pre-assembly – stick, unitised, panelised- quality ; QA, factory work, site work

� Maintenance- access ; cleaning, inspection, repair,

replacement- life cycle ; component life, inspection

cycle, repair, replacement- serviceability ; cleaning, repairability,

replaceability

11.1 Factors of External Walls System

11.2 Type of Walls

� Load Bearing walls

- function as shear walls;generally of reinforcedconcrete.

� Non Load Bearing Walls

- most walls used in tallbuildings are non loadbearing.

- can be reinforced concrete,brick, composite materials,glass, metal sheets etc.

- used to enclose the buildingstructure and provide a‘face’ or façade.



11.3 Type of External Walls

a. Curtain Walling

b. Infill Panels

c. Cladding

a. Curtain Walling� A form of external lightweight claddingattached to a frame structure forming acomplete envelope or sheath aroundthe structural frame.

� Non load bearing claddings which haveto support only their own deadweightand imposed wind loadings which aretransferred to the structural framethrough connectors which are usuallypositioned at floor levels.

� A series of vertical mullions spanningfrom floor to floor interconnected byhorizontal transoms forming openeingsinto which can be fixed panels of glassor infill panels of apaque materials.

� Constructed by using a patent orproprietary systems produced by profilemetal fabricators.



- curtain walling details



- type of curtain walling

� ‘Stick’ curtain walling

� ‘Stick and unit’ curtain wall

� Unitised or panel curtain wall

i. Stick System� Uses site assembledframing members,mullions (verticals)and transoms(horizontal)

� Glazing and infillpanels are fixedinto the carrierframing grid byclamping them intoa glazing rebate

� The infill panelsconsists of mineralwool insulation.

� The carrierframework remainsvisible.

� E.g. Sears Tower.



ii. Stick and unit system

� The panelsare attachedto a sticktype or gridtype or trusstype carrierframeworkfixed to thebuildingstructure.



iii. Unitised system� Large, integralfactory assembledunits, sometimesone storey highincoporatingmineral woolinsulations,windows,ventilators, doorsand opaque facing.

� The panels areonly anchoredeither to thebuilding structureor to both thestructure andadjacent panels.



iv. Structural Glazing� Structural glass panels that are supported by a framework of

moveable spider connectors steel trusses and outriggers.� Popular for the façade of the podium annexes for many tall

buildings� The system allow for high head room as the glass can be span

up to four stories high by an appropriately design framework







b.Infill Panel� The wall is installed between the

exterior floor slab and columnsof the structural frame.

� The panel layout can be soarranged to expose some or allof the structural memberscreating various opticalimpressions.

� Wide variety of materials orcombinations of materials can beemployed such as glass, pre castconcrete, aluminium etc.





c. Cladding

� The wall (in the formof large panel) isattached directly tothe structural frameof the buildings or abacking wall.

� The panels are one totwo storey high andspan one or morehorizontal bays ofstructural frame.

� Require large fixingsand anchors to holdthem on the building.





12.0 FOUNDATION SYSTEM FOR TALL BUILDING12.0 FOUNDATION SYSTEM FOR TALL BUILDING12.0 FOUNDATION SYSTEM FOR TALL BUILDING12.0 FOUNDATION SYSTEM FOR TALL BUILDING

� Refer to foundation notes BLD310 (Diploma in Building) andbasement notes BLD 410(Degree)

� Types of foundation used forTall Building- Piling

: Displacement Piles –Steel H Pile,Spun Pile

: Replacement Piles –Bored Pile,Barretts Pile

- Drilled Caisson- Buoyancy Raft Foundation

a. Bored Pile



b. Drilled

Caisson



c. Spun Pile



d. Barretts Pile

e. Buoyancy Raft Foundation



13.0 CONSTRUCTION OF TALL BUILDINGS

� Nature of Tall BuildingConstruction- Working at Heights: increases the risks of injury ordeaths from falling or being hitby falling objects.

: personnel and materials haveto lifted to their working areaslocated at elevated heights.

- Operating in RestrictedWorking Area: usually in built up areas onsmall sites

: not much working space atground level.

- Repetitive Work Activities: usually repeating a cycle ofactivities associated witheach floor.

13.1 Method of Construction

� Conventional

- In Situ Reinforced Concrete

� Industrialised Building System (IBS)

- Prefab System

- Industrialised Formwork System

- Steel Structures



a. Conventional – reinforced concrete

� Refer to Diploma Notes and Encik Kamran Notes in BLD 460 (Bach of Construction Management)

b. IBS – Prefab System

� Refer to PM Mafozah Murad Notes in BLD 460 (Bach Construction Management)



� Refer to PM Mafozah Murad Notes in BLD 460 (Bach of Construction Management)

b. IBS – Steel Structures

Types of Formwork� Prefabricated Job Built Forms that can be reused, usually

referred to as gang or gang forms.� Manufactured Forms, generally purchased or leased,

sometimes as a total system.

b. IBS - formwork



i. prefabricated job-built forms� prefabricated forms are usually constructed substantiallyfor the purpose of frequent reuse, commonly used for wallforming, and also for deck forming where multiple floorsare being erected.

� these forms can either be ready made or custom made.

� Gang or Ganged Forms

� Flying forms

- gang or ganged forms• are built by assembling a number of small prefabricated panel forms into one large form.

• can be used on all types of work, their size being limited only by job conditions and the

means for moving them. These large sections are erected, stripped and moved to the

next location by cranes.

• provides good reuse of equipment, larger concrete placements and decreased erection

and stripping time because the sections stay intact.

• no dismantling and reassembly of each individual panel for each concrete placement.





- flying / table forms• are large prefabricated forms for multi-storey building slabs.

• contain their own supporting system and levelling jacks, and are easily dropped

away from the floor slab when the concrete reaches the specified strength.

• the form is then moved to the edge of the building, picked up by a crane, and

moved to the next floor for setting and levelling.

• the name ”flying formwork” is used because forms are flown from story to story

by a crane



ii. manufactured forms� speciality manufactured forms that reduce the time andlabour formerly required at job sites

� these systems and panels are durable enough for manyreuses.

� each proprietary panel systems has its own special tiesand other accessories.



- pan forms• made of metal, fibreglass or plastic are used for floor slabs in multi-storey

building .

• waffle slab floors have waffle-like indentations on the bottom surface formed

by rectangular pans in the same manner as in the pan joist floor system.

• these forms are reusable and can be either rented or bought.

• they come in a wide range of sizes and depths.





- internal forms• are round or rectangular laminated fibre

and cardboard forms placed in deep

(or thick) floors or beams and left in

place to lighten the dead weight of

member

• these produce a floor slab similar to the

pan joist floor except both top and

bottom surfaces are flat.

• the duct like void create a space

between the joists, inside of the

element.

• the ends of the tubes and boxes are

closed off so that concrete will not flow

into them

• expanded polystyrene can also be used

to create internal voids

- tunnel forms

� combined the walls on either side of a room and the slab overhead soffit

from into a single unit.

� typically, the wall forms hinge to allow the slab soffit form to be stripped,

and the entire assembly is hoisted to the subsequent area to be formed



- column forms•square or rectangular columns can

be built using the same system of

form panels as used for walls.

•forms for round columns are

available in laminated fiber, metal

and glass fiber reinforced plastic

as complete units



- slipforms

• Slipforms place concrete by extrusion.

• The concrete is placed in the forms, which are then pulled or jacked vertically

or horizontally, extruding the concrete, in the shape of the forms.

• The most spectaculars use of slipforms is for tall towers, silos, elevator shafts

in tall buildings and building walls.

• The movement of the forms is slow enough for concrete to gain the strength to

keep its shape and support its weight.



- jump forms / climbing forms• similar to slipforms except that rather than extruding the concrete, the form is

filled with concrete, stripped and then ‘jumped’ to the next level after the

concrete has set.

• these gang forms may be lifted by crane or self raised (electrically or

hydraulically).

• properly designed, they minimize the number of pieces to be handled and

simplify the task of resetting the forms while meeting the tolerances specified



Jump form operation



Jump form operation

- stay-in-place forms• these forms are often steel or thin precast, prestressed concrete units that

are placed on supporting formwork (when used for floors) and bonded to

become the bottom of the concrete element.

• become part of the completed structure.

• they are often used for concrete floor and roof slabs cast over steel joists or

beams, for bridge decks, for a top slab over a pipe trench or for other

inaccessible locations where it is impractical and expensive to remove

forms.



13.2 Vertical Transportation& Handling / Elevated Access

� Access to the interior and exterior of the building is neededfor workers, materials and even plant or machinery.

� Workers have to be lifted to their work areas within thebuilding being built so that they do not tire themselvesclimbing stairs.

� Materials have to be lifted to their installation positionswithin the building being built.

� The common equipment or machineries used are:- Scaffolding- Cranes- Derricks- Gondolas/Swinging Stage- Hoists- Elevator (lifts)- Helicopters- Rubbish Chute

a. Scaffolding� A temporary working platform

erected around the perimeterof a building structure usuallyconstructed from steel oraluminium alloy tubes clippedor coupled together to providea means of access to highlevel working areas as wellproviding a safe platform fromwhich to work.

� Supported from the ground or on a floor slab or platform

� Remain static and difficult to move.

� Types of Scaffolding:

� Putlog scaffolds� Independent scaffolds� Cantilevered Scaffolds� Truss-out scaffold� Gantries



- component parts of tubular scaffold:

i. putlog scaffolds

These are scaffoldswhich have an outerrow of standardsjoined together byledgers which in turnsupport thetransverse putlogswhich are built intothe beds joints orperpends as the workproceeds, they areonly suitable for newwork in bricks orblocks.



ii. independent scaffolds

� These are scaffoldswhich have two rowsof standards each rowjoined together withledgers which in turnsupport thetransverse transoms.

� The scaffold iserected clear of theexisting or proposedbuilding but is tied tothe building orstructure at suitableintervals.

� Tying-in� All putlog andindependent scaffoldsshould be tied securelyto the building structureat alternate lift heightsvertically and not morethan 6m centreshorizontally.

� Suitable tying-inmethods includeconnecting to tubesfitted between sides ofwindow openings or tointernal tubes fittedacross windowopenings.



iii. cantilever scaffolds� These are a form ofindependent tiedscaffold erected oncantilever beams andused where it isimpracticable,undesirable oruneconomic to use atraditional scaffoldraised from groundlevel.

� Requires special skillsand should thereforealways be carried outby trained andexperienced personnel.

iv. truss-out scaffold

� A form of independenttied scaffold used whereit is impracticable,undesirable oruneconomic to build ascaffold from groundlevel.

� The supporting scaffoldstructures is known asthe truss out.

� Requires special skillsand should thereforealways be carried out bytrained and experiencedpersonnel.



v. gantries� These are elevatedplatforms used whenthe building beingmaintained or underconstruction isadjacent to a publicfootpath.

� A gantry over afootpath can be usedfor storage ofmaterials, housingunits ofaccommodation andsupporting anindependent scaffold.

b. Cranes� These are lifting devices designed to raise materials by means of rope operation and move the load horizontally within their limitations of any particular machine.

� The range of cranes available is very wide and therefore choice must be based on the loads to be lifted, height and horizontal distance to be covered, time periods og lifting operations, utilisation factors and degree of mobility required

� Types of crane:

�Mobile Crane� Static Crane� Tower Crane



- types of crane

i. Mobile Crane – Self Propelled Cranes

Mobile cranesmounted on awheeled chassisand have onlyone operatorposition fromwhich the craneis controlledand the vehicledriven



i. Mobile Crane – Lorry Mounted Cranes

� Mobile cranes consistsof a lattice or telescopicboom mounted on aspecially adapted truckor lorry.

� Have two operatingpositions: the lorrybeing driven from aconventional front caband the crane beingcontrolled from adifferent location.

� The lifting capacitiescan be increased byusing outriggerstabilizing jacks.



i. Mobile Crane – Lorry Mounted Lattice Jib Cranes

� These cranes followthe same basicprinciples as thelorry mountedtelescopic cranesbut they have alattice boom andare designed asheavy duty craneswith liftingcapacities in excessof 100 tones.



i. Mobile Crane – Track Mounted Cranes

� These machines can be auniversal power unitrigged as a crane or apurpose designed trackmounted crane with orwithout a fly jibattachment.

� The latter type areusually more powerfulwith lifting capacities upto 45 tonnes.

� Can travel and carry outlifting operations on mostsite without the need forspecial road andhardstands provisions butthey have to be riggedon arrival after beingtransported to site on alow loader lorry.

ii. Static Crane - Mast Cranes

� Similar in appearance tothe familiar towercranes but they haveone major difference inthat the mast or toweris mounted on theslewing ring and thusrotates whereas a towercrane has the slewingring at the top of towerand therefore only thejib portion rotates.

� Self erecting, ofrelatively low liftingcapacity and are usuallyfitted with luffing jib.



iii. Tower Cranes� Most tower cranes have to be assembled and erected on site prior

to use and can be equipped with a horizontal of luffing jib.� Wide range of models available often makes it difficult to choose

a crane suitable for any particular site but most tower cranes canbe classified into one of four basic groups:� Self Supporting Static Tower Cranes� Supported Static Tower Cranes� Travelling Tower Cranes� Climbing Cranes

Example of Tower Cranes Details:



iii. Tower Cranes – Self Supporting

Static Tower Crane

� High liftingcapacity withthe mast ortower fixed toa foundationbase.

� Suitable forconfined andopen sites.

iii. Tower Cranes – Supported Static

Tower Cranes

� Similar inconcept to selfsupportingcranes and areused where highlifts are required,the mast ortower being tiedat suitableintervals to thestructure to giveextra stability.





iii. Tower Crane – Travelling (Rail

Mounted) Tower Crane

� Mounted on powerbogies running ona wide gaugerailway track togive greater sitecoverage.

� Only slightgradients can beaccommodatedtherefore areasonably levelsite or speciallyconstructedrailway supporttrestle is required.

iii. Tower Crane – Climbing Cranes

� Used in conjunctionwith tall buildings andstructures.

� The climbing mast ortower is housedwithin the structureand raised as theheight of thestructure isincreased.

� Upon completion thecrane is dismantledinto small sectionsand lowered downthe face of thebuilding



- parts of a Tower Crane� All tower cranes consist ofthe same basic parts:� The base is bolted to alarge concrete pad thatsupports the crane.

� The base connects to themast (or tower), whichgives the tower crane itsheight.

� Attached to the top of themast is the slewing unit-- the gear and motor --that allows the crane torotate:



� On top of the slewing unit arethree parts:� The long horizontal jib (orworking arm), which is theportion of the crane that carriesthe load. A trolley runs alongthe jib to move the load in andout from the crane's center:

� The shorter horizontalmachinery arm, whichcontains the crane's motors andelectronics as well as the largeconcrete counter weights:

� The operator's cab:

� The machinery arm contains themotor that lifts the load, along withthe control electronics that drive itand the cable drum, as shown here:

� The motors that drive the slewingunit are located above the unit'slarge gear:

� Tower cranes arrive at the construction site on 10 to 12 tractor-trailer rigs.

� The crew uses a mobile crane to assemble the jib and themachinery section, and places these horizontal members on a 40-foot (12-m) mast that consists of two mast sections.

� The mobile crane then adds the counterweights. The mast risesfrom this firm foundation. The mast is a large, triangulated latticestructure, typically 10 feet (3.2 meters) square. The triangulatedstructure gives the mast the strength to remain upright.

- how do they grow?



� To rise to its maximum height, thecrane grows itself one mast sectionat a time! The crew uses a topclimber or climbing frame that fitsbetween the slewing unit and the topof the mast. Here's the process:� The crew hangs a weight on the jib tobalance the counterweight.

� The crew detaches the slewing unitfrom the top of the mast. Largehydraulic rams in the top climberpush the slewing unit up 20 feet (6m).

� The crane operator uses the crane tolift another 20-foot mast section intothe gap opened by the climbingframe. Once bolted in place, thecrane is 20 feet taller!

� A typical tower crane has the followingspecifications:� Maximum unsupported height - 265 feet (80

meters)The crane can have a total height much greaterthan 265 feet if it is tied into the building as thebuilding rises around the crane.

� Maximum reach - 230 feet (70 meters)� Maximum lifting power - 19.8 tons (18 metric

tons), 300 tonne-meters (metric ton = tonne)� Counterweights - 20 tons (16.3 metric tons)

� The maximum load that the crane can lift is 18metric tons (39,690 pounds), but the cranecannot lift that much weight if the load ispositioned at the end of the jib. The closer theload is positioned to the mast, the more weightthe crane can lift safely. The 300 tonne-meter rating tells you the relationship. Forexample, if the operator positions the load 30meters (100 feet) from the mast, the cranecan lift a maximum of 10.1 tonnes.

- how much weight can they lift?



� The crane uses two limit switches tomake sure that the operator does notoverload the crane:� The maximum load switch monitors thepull on the cable and makes sure that theload does not exceed 18 tonnes.

� The load moment switch makes sure thatthe operator does not exceed the tonne-meter rating of the crane as the load movesout on the jib.

� A cat head assembly in the slewing unitcan measure the amount of collapse in thejib and sense when an overload conditionoccurs.

- why don't they fall over?� The first element of the towercrane's stability is a largeconcrete pad that theconstruction company poursseveral weeks before thecrane arrives.

� This pad typically measures 30feet by 30 feet by 4 feet (10 x10 x 1.3 meters) and weighs400,000 pounds (182,000 kg)-- these are the padmeasurements for the craneshown here.

� Large anchor boltsembedded deep into this padsupport the base of the crane:



c. Derricks

� The Derricks crane is asimple and inexpensivesolution for lifting heavyweights (10 tonnes ormore) at long radius (up to30m)

� Two types:

�Guy Derrick

�Scotch Derrick

i. Guy Derrick� Guy Derrick hasseveral guys (cableties) that holding upthe mast and to helpslewing of the cranesboom.

� The other ends of theguys are anchored tothe building structure.

� The boom is hinged tothe base of the mast.

� Winches located atthe mast base.: useto derrick the boomand hoisting the load



ii. Scotch Derrick

� Similar in designto the guy derrickexcept that it hasno guys (cableties), has a shortermast and a longerboom.

� It is stabilized byhaving its twobackstays to beloaded withballast.



d. Gondolas or Swinging Stage� These consists of a working

platform in the form of a cradlewhich is suspended fromcantilever beams or outriggersfrom the roof of a tall building togive access to the façade forcarrying out light maintenancework and cleaning activities.

� The cradles can have manual orpower control and be in singleunit or grouped together to forma continuous working platform. Ifgrouped together they areconnected to one another at theirabutment ends with hinges toform a gap of not more than25mm wide.

� Many high rise building have apermanent cradle systeminstalled at roof level and this isrecommended for all buildingsover 30m high.



e. Hoists� These are designed for thevertical transportation ofmaterials, passengers ormaterials and passengers.

� Materials hoists are designedfor one specific use (i.e. thevertical transportation ofmaterials) and under nocircumstances should theybe used to transportpassengers.

� Most material host are of amobile format which can bedismantled, folded onto thechassis and moved toanother position or siteunder their own power ortowed buy a haulage vehicle.

� Passenger hoists aredesigned to carrypassengers althoughmost are capable oftransporting acombined load ofmaterials andpassengers within thelifting capacity of thehoist.

� A wide selection ofhoists are availableranging from a singlecage with ropesuspension to twincages with rack andpinion operationmounted on two sidesof a static tower.



f. Elevators (lifts)

� These move on tracks.

� They are more stable and have higher capacitiesas compared with a gondola.



g. Helicopters� When it is not possible touse crane to lift thetopmost part of thebuilding (such astelecommunication towermast) helicopterbecomes a viablesolution despite its veryhigh cost.

g. Rubbish Chutes� Used to direct disposals ofdebris from various floor tothe bin on the ground floor

� The simple concept ofconnecting severalperforated dustbins.

� The tapered layeredcylinders are producedfrom reinforced rubberwith chain linkage forcontinuity. Overall lengthare generally 1100mm,providing an effectivelength of 1m.

� Hoppers and side entryunit are mede for specialapplications.



13.3 Working Space

� Space is limited.

� Among approaches to provide sufficient work space so that work can be done safely and efficiently:

� multistory site accommodation.

� elevated site accommodation and platforms.

� use part of uncompleted structure.

� use nearby properties and public spaces.

� maximising prefabrication and standardisation



a. Multi story site accommodation

� Usually portable container cabins -stacked up.

b. Elevated site accommodation and

platform

� site accommodationbuild upon scaffolding /gantry such that thesite accommodationopens up to the streetlevel.

Gantry to support

cabin



c. Use part of uncompleted structure

� When the building is partially complete, it may be feasible to use some of the completed floor as site accomadation.

d. Use nearby properties and public spaces

� Rent space in an adjacent building for site accommodation.



e. Maximising prefabrication and

standardisation

� If the contractor usesprefabricatedcomponents for thebuilding, there is noneed for space at siteto store the rawmaterials.

� The components arebuilt off site andtransported to the siteto be assembled intotheir final positions

14.0 Safety System For Tall Building Construction

� The great heights, strong winds at heights and constricted working space make fatal falls and collisions very possible.

� Most accidents in a worksite are categorized under :� “falls of person”

� “workers struck by falling objects”

� Accidents may result in high direct and indirect costs:� Direct Costs : medical costs, workers’ compensation and other insurance benefits.

� Indirect Costs : reduced productivity, job schedule delays, damage to equipment and facilities, low morale among workers and possible additional liability claims.



14.1Falls of Person� Measures against fall of persons:� A working platform shouldbe provided to workerswhenever practicable :should be of adequatewidth, carrying capacity andwith sufficient guardrails toafford a safe and steadyfoothold and handhold. Thewidth should not be lessthan 635mm and toe-boardsmust be provided.

� Safety belts and lifelines;in the case where platformcannot be provided forreasons of space constraint.

Safety Belt



14.2 Falling Objects

� Measures against person struck byfalling objects include:� Good housekeeping and minimizing debrisbeing generated, hence less falling materials.

� Systematic and regular disposal ofaccumulated debris, provisions of perimeteroverhead shelter.

� Access and egress shelters to building:provision of safety nets and provision ofpedestrian walkway or hoarding

� The compulsory wearing of safety helmets.

Safety Helmet

Sidewalk Shed Protection Safety Netting



Safety Net Catch Platform

CASE STUDY:� PETRONAS TWIN TOWERS….

� TURNING TORSO, SWEDEN….

� BURJ HOTEL, DUBAI……



THANK YOU

Documents

Tall Building MKA Jan 2011