Pwd Final Report

7/29/2019 Pwd Final Report

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Summer Vocational Training 2012

4 Lane Elevated Corridor From Keshtopur To Jora Mandir On Kazi Nazrul

Islam Avenue [VIP Road] Page 1

Chapter 1: Introduction

1.1 BACKGROUND

Kazi Nazrul Islam Avenue, also known as VIP road is one of the major arterial roadsof Kolkata providing critical connectivity to the Netaji Subhas Chandra Bose

International Airport as well as to an increasing no. Residential colonies and

institutions. It starts at Ultadanga in the city core and near the airport, having total

length about 8km. It also acts the main link roads for the traffic entering the city as

well as NH2 or via NH6 (via Belghoria Expressway) as well as NH34, NH35 from

northern side of Kolkata, thereby catering to the significant quantum of through traffic

using this road.

Over the years, massive ribbon development comprising of residential, commercialand institutional activities along this corridor has started generating a huge volume of

local traffic and significant cross traffic along this corridor thereby resulting in the

massive congestion and vehicle-vehicle and vehicle pedestrian conflict at several busy

crossings. The conflict between through traffic and cross traffic at several busy

interactions has also seriously impeded the smooth and speedy movement of traffic

thereby hindering urban mobility and also endangers the safety of the urban residents.

To address this impediment to traffic movement, provide security to the residents andcater to the growing travel demand as well as substantial ribbon like urban

development along the road, a grade separation in the form of an elevated corridor is

considered to be the only viable solution for smooth flow of traffic through the

provision of two tiers of the carriageway, the upper tier as elevated corridor to cater to

the through traffic and the other, i.e. the lower tier which will be existing carriagewaywith the necessary improvement to cater to the local traffic with the provision of

service roads and facilities for non-motorized traffic and footpaths for pedestrians in

the line with the requirements of the National Urban Transport Policy (NUTP) of the

Ministry of Urban Development, Govt. of India. Additionally to facilitate smooth and

safe pedestrian crossings particularly at Keshtopur, Baguihati and Jora Mandir,

pedestrian underpasses at these locations have been proposed.

1.2 OBJECTIVE AND NEED FOR THE PROJECT


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The need for an efficient transportation system and network to ensure uninterruptedmobility in and around the city and from/to its only airport has been felt for quite

some time. Over the last decade due to massive ribbon development comprising of

residential, commercial and institutional activities along the Kazi Nazrul IslamAvenue (KNIM) which is the main artery to the city airport has started generating a

huge volume of local traffic and significant cross traffic along this corridor thereby

resulting in massive congestion and vehicle-vehicle and vehicle-pedestrian conflict at

several busy crossing. The conflict between through traffic and cross traffic at several

busy intersections has also seriously impeded the smooth and speedy movement of

traffic thereby hindering urban mobility.

To cater to this growing travel demand while addressing the impediment due to theribbon development along the road, a grade separation in the form of an elevated

corridor is considered to be the only viable solution for smooth urban mobility along

VIP Road.

The proposed elevated corridor will form part of the major linkage between thesouthern part of the Kolkata Metropolitan Area (KMA), central business district of

Kolkata, north eastern part of KMA where the international airport of the city is

located and the north 24 paraganas district. The decadal population growth rate in

north 24 paraganas district is 22.62 percent, which is an indication of huge growth in

population in the north eastern fringe of the city of Kolkata. This growth in population

has resulted in enormous growth in traffic both through as well as cross, leading tomassive traffic congestion along stretches of the Kazi Nazrul Islam avenue thereby

increasing travel time to the citys only airport and also creating huge traffic snags for

the movement of the local residents. The airport traffic also endangers the movement

of pedestrians and non-motorized vehicles lying on the stretch.

In order to overcome traffic congestion and enhance urban mobility along KaziNazrul Islam Avenue (VIP Road) and providing safe movement for the local

pedestrians and minimise the increasing conflict of local and through traffic, it has

been proposed to build the elevated corridor that would segregate the local trafficfrom through traffic and eliminate the conflict at the major locations of Keshtopur,

Baguihati and Jora Mandir and also facilitate smooth and safe pedestrian crossings

through pedestrian underpasses in line with the provisions of the NUTP.

1.3 DESCRIPTION OF THE PROJECT CORRIDOR

The total length of the corridor over which the elevated road has been proposed is 2kms. It will follow the existing alignment of the Kazi Nazrul Islam Avenue or VIP

Road along its central verge with minor geometric correction if found necessary. Thelocation of the proposed elevated corridor is shown in the enclosed index map.


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The project area being a very critical urban corridor is maintained by the PWD Roads,Govt. of West Bengal under its jurisdiction. The project corridor is of significant

importance as it connects the citys only airport, serves as gateway to Kolkata from

other districts within or outside KMA and also other states and also caters to anincreasing volume of urban population. Massive ribbon development can be observed

along the corridor resulting vehicle-vehicle and vehicle-pedestrian conflict at several

locations most prominent among which is Kestopur, Baguihati and Jora Mandir.

Development along the corridor is of mixed nature thereby generating mixed traffic.

These include major commercial areas of Keshtopur clubbed with residential and

institutions such as schools colleges etc. Between Keshtopur and Baguihati prominent

showrooms of leading car manufacturers can be seen. College more, Baguihati and

Jora Mandir has also undergone massive mixed use development with a number of

hospitals, banks, commercial establishments, institutions, a large market and huge

residential localities. The land adjacent to the road at Baguihati is used as parking lot

and terminal for busses originating from Baguihati to various locations in KMA.

Besides, PWD mechanical workshops and stack yard is located adjacent to the project

stretch. The Baghjola canal crosses the project corridor at Keshtopur via a skewed

bridge with sluice gates. There are a no. of cross roads at Keshtopur, college more,

Baguihati and Jora Mandir which carry considerable cross traffic that are of mixed

nature out of which a large no. of pedestrian traffic can be observed. Traffic along the

project corridor is of mixed nature varying from heavy traffic like busses, trucks etc.

to medium and light commercial vehicles to auto rickshaws, two wheelers and non-

motorized traffic comprising of rickshaws , bicycles and pedestrian traffic.


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INDEX MAP


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Chapter 2: Environmental and social impact study

2.1 INTRODUCTION

In order to identify the environmental issues related to the activities for construction of a road

with two separate ramps between Keshtopur and Jora Mandir on Kazi Nazrul Islam Avenue

(KNIA) also known as VIP Road an environmental social assessment were carried out on thebasis of secondary data. Environmental assessment includes the study of present

environmental set-up in and around the project influence area.

2.2 STUDY OBJECTIVES

The objectives of the environmental assessment are to enable early determination and

evaluation of potential impacts on ambient environment due to project related activities

during construction and operation phases and thereafter examination of level of study

required in the succeeding period. The Environmental assessment would also help to design

the project in an environmentally sustainable and socially acceptable mode by incorporatingenvironmental regulations and suggestion made by the possible funding institutions.

2.3 ENVIRONMENTAL IMPACT ASSESSMENT REQUIREMENT OF THE PROJECT

Regional Environmental Settings

Anticipated Environmental Impacts and Mitigation Measures

Environmental Impactsconstruction phase On Air Quality On noise level On water quality On soil On Ecology

Causes of Impacts on Air Quality

Land clearing


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Construction of pavementsNoise pollution will be caused by

Operation of construction equipments such as earth moving and material handlingequipments.

Cause of Impacts on Water Quality

Water quality may deteriorate from runoff and waste generated from constructionactivities.

Impact on Soil

Contamination of soil is expected due to deposition of construction materials andwaste products as well as fuel and lubricant spillage from vehicles.

Impacts on Ecology

Unforeseen accidents could result in personal injuries and damage to private orpublic property.

Environmental Impactsoperational phaseDuring operational phase the environmental impacts are likely to be mostly positive.

However there could be some adverse impacts due to inadequateoperations/maintenance/control. Increase in air pollution is expected during the operation

phase since traffic volume is predicted to be high. It is essential that appropriate traffic safety

measures are included in project design.

Road safety and Traffic Management during Construction

Contractor in consultation with PWD, (Road) will have to prepare a trafficmanagement plan for approval of the State Police. The plan will include:

Measures to be taken to prevent traffic congestion. Provision of temporary safe access to school/residence that will be blocked due to

construction.


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Measures to be taken for safe passage of traffic including temporary diversions andseparation of motor vehicle traffic from non-motorised and pedestrian traffic where

necessary.

Measures to be taken to ensure safety to traffic passing through the construction areaincluding signs, marking flags, lights and flagmen as may be required.

2.4 SOCIAL IMPACTS

The following sections discuss the social impacts of the proposed project and also focus on

the various conclusions and recommendations in order to eliminate adverse effects on thesocial environment of the study area.

Social Impact Assessment

Baseline situation of certain well-defined pockets have been studied while discussing the

social setting of the immediate project area. These pockets include following:

Ultadanga Multi-Point Crossing VIP Road (along the Keshtopur Canal) Lake Town Bangur Avenue DumDum Park Areas adjacent to proposed elevated corridor like Keshtopur, Baguihati and Jora

Mandir.

Ultadanga Multi Point CrossingThe Ultadanga Intersection is adjacent to HUDCO more. Different kinds of shops are seen in

this place .A footbridge has been constructed at this multi point crossing to facilitate

movement of pedestrian traffic. Heavy traffic movement marks this densely built-up area.

Noise pollution and air pollution levels are high. This is basically a commercial location. The

social nature of this area is truly cosmopolitan.


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VIP Road and GolaghataHigh-rise multi-storied apartments, factory warehouses, vehicle showrooms, commercial

establishments, stationery shops, resorts, restaurants, vacant spaces etc. are noticed along VIP

Road. The Keshtopur Canal runs parallel to the VIP Road. This is the single major road

leading to the Netaji Subhash International and Domestic Air Terminal Dum Dum . Vehicular

traffic level is considerably high. A large population that provides a range of domestic and

professional services in capacity of domestic helps, drivers, cooks, maids, shop assistants,

garage boys, telephone booth operators, photocopier operators, attendants etc. also lives in

this area. Water bodies are also seen along the VIP Road. Large advertisements are noticed

along the roadside. These are lit up during the evening.

Lake TownHigh-rise multi-storied apartments, factory warehouses, vehicle showrooms, commercial

establishments, stationery shops, resorts, restaurants, vacant spaces etc. are noticed in Lake

Town. A large population that provides a range of professional services also seen in Lake

Town. There is a footbridge constructed across the VIP Road connecting Lake Town with

Salt Lake City.

Bangur AvenueHigh-rise multi-storied apartments, factory warehouses, vehicle showrooms, commercial

establishments, stationery shops, resorts, restaurants, vacant spaces etc. are noticed in Bangur

Avenue. Well-to-do section of the society live in the affluent apartments here.

Dum Dum ParkThis area is also similar to Bangur Avenue in its characteristics and social fabric with high

rise multi storied residential apartments and commercial establishments, restaurants.


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Chapter 3: Engineering Surveys & Investigation

A detailed ground reconnaissance of the project road was undertaken after the study of maps

and preliminary data collected. Separate teams were deployed along the roadway section to

conduct surveys and investigation, the summary of which is enlisted in succeeding sections.

3.1 TOPOGRAPHIC SURVEY

EQUIPMENTS Electronic total station with angular accuracy of 1 sec Auto Level having accuracy of 2.5 mm/km Other items like measuring tapes, ranging rods, etc. as required. STANDARD CODES USED IRC:SP 19-2001 IRC:SP 13 SURVEY PROCEDURE Location of Temporary Bench Marks(TBM) Fixation of Temporary Bench Mark(TBM) Levels

All leveling are carried out from the GTS BM located at Baguihati Central Godown,

Baguihati, under Alipore Sub-Division having value of 3.943 with Auto Level

having accuracy 2.5 mm/km.


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Details of TBM points have been furnished in the table below:

TBM

No.

Chainage

(km)

Northing

(N)

Easting

(E)

Elevation

(Z)

Side Offset from

center

Line(m)

TBM-1 3.168 10830.91 11295.66 3.781 Right 19.55

TBM-2 3.219 10884.15 11307.08 3.840 Right 20.53

TBM-3 4.280 11456.34 12172.67 3.710 Left 16.00

TBM-4 4.355 11493.59 12236.90 3.531 Left 13.13

TBM-5 4.603 11618.95 12454.90 3.531 Right 15.52

TBM-6 4.654 11646.43 12498.06 3.326 Right 14.90

Taking detail Survey Readings Ground Features Take Off Survey Coding Guidelines for Typical Feature Surveys Long Sections Cross Sections Cross Section at Culverts Temporary(TEMP) Stations

Survey Controls The entire topographic survey has been carried out by Total Station having

facility of transferring data to computer.

All transverse stations were recorded with X,Y and Z co-ordinates and werechecked to eliminate any error.

The TBMs were connected for X and Y co-ordinates by Total Stations withclosing at intervals.

Levels of all Temporary BMs were obtained by Auto Levels only. Levels wereclosed to eliminate any error. However, subsequent leveling from TBMs for

contouring purpose(detailing) have been carried out by Total Station.


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Ground Verification Digital Terrain Modeling (DTM)

3.2 ROAD AND PAVEMENT INVESTIGATIONS

Road Inventory Survey Pavement Investigation

Pavement Condition Survey

a) Pavement Condition Surveyi. Pavement

Cracking(narrow and wide) Ravelling(% of pavement area affected) Potholing(% of pavement area affected) Edge Break(length in meters) Rut depth(in mm)

ii. ShoulderShoulders are unpaved and their condition

is indicated along with pavement condition

b) Subgrade Characteristics and StrengthAfter dividing the road into homogeneous segments with

respect to pavement condition and strength, soil classificationand mechanical characteristics of subgrade soil along the

existing road alignment have been carried out by digging pits

@ 1 pit per km in a staggered manner on both sides of the

road. The tests include :

In-situ density and moisture content of sample of eachpit

Grain Size Analysis Atterberg Limits Modified Proctor Test Laboratory CBR


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Chapter 4: Construction Programme

4 .1 CONSTRUCTION EQUIPMENT:

The project is basically a decongestion and capacity augmentation project by constructing

one elevated corridor along with construction of service road, footpath cum drain and

widening of main carriageway including two numbers culverts. All necessary equipments/

machineries for fully mechanized construction will be necessary for timely implementation of

the project. The list of equipments given below in the table includes the machineries related

to the earthworks, base/ sub-base works, concrete works, structural works and other

miscellaneous works.

4.2 CON STRUCTION PROGRAM M E AND M ETHODO LOGY:

The construction methodology envisages composite super structure with steel pier in the

viaduct portion. The main purpose of adopting this type of construction is to minimize the

disruption in traffic flow during construction period and also to reduce the tenure of

construction period. During construction, central portion of selected stretches of VIP road

shall have to be barricaded. The steel column and & girders will be fabricated at workshop

and transported to site by trailer. The size of single piece will guide the location of splicing.

The girders will be launched on piers and the deck slab will be cast by taking temporary

support from the girders. After completion of decking, crash barrier, expansion joint, railing

and all the appurtenances will be fixed and wearing course will be laid. The embankment

portion of the flyover will be constructed by R.E wall.

The total duration of project construction period has been considered as 20 months.


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List of Equipments:

Type of Equipment Output of Machine Remarks

Air Compressor 1250 sqm/hr Surface cleaning

Batching and mixing plant 15-20 cum/hr Concrete MixBatching and mixing

plant(30cum)

30 cum/hr Concrete Mix

Concrete Mixer(0.4/0.28 cum) 2.5 cum/hr Concrete Mix

Concrete Pump 25 cum/hr Concrete Mix

Crane-35T 35 Tonne For lifting



Dozer D-50-A 15 150 cum/hr Clearing

Dozer D-80-A12 180 cum/hr Clearing

Front-end Loader 25 cum/hr Aggregate Loading

Generator 300 KVA 300 kva Hot Mix Plant

Generator 100 KVA 100 kva WMM Plant

Hot Mix Plant(60-90 TPH) 60-90 cum/hr Asphalt Mix

Hydraulic Excavator 60 cum/hr Excavation

Mastic Cooker 1 tonne/hr Mastic asphalt

Mechanical Broom 1250 sqm/hr Surface cleaning

Motor Grader(3.35 m blade) 50 cum/hr GSB Spreading

Motor Grader(3.35 m blade) 200 cum/hr Soil Spreading

Paver Finisher(with sensorcontrol)

30 cum/hr Asphalt Mix Laying

Piling rig with Bentonitepump

2 to3 RM/hr Boring

Pressure distributor(Bitumen) 1750 sqm/hr Tack coat/ Prime coat

Pressure distributor(Emulsion) 1750 sqm/hr Tack coat/ Prime coat

Road Marking Machine 100 sqm/hr Road Marking

Roller(Ordinary) 70 cum/hr Earth/ Soil

Roller(Pneumatic tyred) 25 cum/hr Asphalt works

Roller(Tandem) 30 cum/hr Asphalt works

Roller(Vibratory) 100 cum/hr Earth/ Soil

Tipper/ Trucks 5.5 cum All kinds of material

Transit Mixer 3 cum/hr Transportation of concrete

mix

Transit Mixer 4.5 cum/hr Transportation of concrete

mix

Wet Mix Plant(60 TPH) 60 Tonne/hr WMM


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Chapter 5: Cost Estimation and Rate Analysis

5.1 GENERAL

The methodologies adopted for estimating the cost of the proposed elevated corridor and its

ancillary works which may be divided be divided in three board items of works as follows:

Proposed elevated corridor Improvement of existing road and Proposed pedestal subway

For each item of work the cost estimate has been arrived based on following steps:

Analysis of unit rates of various items of work. Estimation of quantities for site clearance & utility relocation. Estimation of quantity for earthwork and road components e.g. pavement, cross

drainage structures, bridges etc. and other ancillaries as per relevant IRC/IS and

MoRTH specifications. Consideration of allowances for contingencies.

5.2 ANALYSIS OF RATES:

The rates of various item of works associated with the proposed project has been arrived

based on public works (roads ),directorate ,schedule of rates ,2008 government of West

Bengal with latest addendum and corrigendum issued on 1st

July ,2010. Considering cost of

materials, machinery and labour with additional percentages to concider Over head Chargesand Contractors profit. The said schedule of Rates follows the guidelines furnished in

MoRT&Hs Standard Data Book (first revision 2003).

Rates of item of works which are not covered in schedule of rates, 2008 of public works

(roads) directorate, the rates have been taken from PWD, NH Schedule of Rates,2007-2008

Govt. of West Bengal. Moreover the rates of structural steel & bolt including fabrication &

erection have been analyzed considering the present market rate.

The contractors profit has been considered on all items at uniform rate of 10%. The profit

has been considered applicable on material, machinery, labour cost and overhead charges, asper the MoRTH Standard Data Book.


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5.3 COST ESTIMATE:

The cost estimate of the project has been delivered based on the rates for various items of

work taken from schedule of different departments.

The estimated cost of the project amounts Rs. 208,03,88,745 (Rupees Two Hundred EightCrores Three Lakhs Eight Eighty Thousand Seven Hundred Forty Five only).

The abstract of the estimated cost of the project is provided in the table below:

SL NO. ITEM OF WORK AMOUNT(Rs.) REMARKS

A. Proposed Elevated Corridor

Foundation 18,18,98,118 Substructure 32,63,14,822 Superstructure 107,40,15,814 Approach ramp 2,15,93,387 Miscellaneous 34,49,971

Subtotal ( Proposed Elevated

Corridor)

160,72,72,112

B. Improvement of existing road

1. Road works 144810723

2. Side drain 80854994

3. CD structure 15396854

4. Miscellaneous works 20079056

Sub total ( Improvement of existing

road)

261141627

C. Proposed pedestrian subway

Subway at Kestopur 17403694 Subway at Baguiati 18743098 Subway at Jora

mandir

17144904

Sub Total( Proposed pedestriansubway)

53291696


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Chapter 6:Subgrade Soil Investigation

SUBGRADE SOIL INVESTIGATION

In order to access the existing pavement composition including subgrade soil properties test

pits of size 1.00m*1.00m were excavated at the pavement shoulder interface down to the

subgrade level.

The following tests are performed on the soil sample:

A field dry density using sand replacement method was carried out at the subgrade levelas per IS:2720(Part 28).

On the soil sample collected from the top 300mm of subgrade classification and thefollowing laboratory tests were performed:

Field moisture content(as per IS:2720(Part 2)- 1973) Grain size analysis(as per IS:2720(Part 4)- 1985)Grain size analysis express quantitatively the proportions by mass of the various size of

particles present in the soil.


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Atterberg Limits(as per IS:2720(Part 5)- 1985) Plastic limit: The plastic limit of fine-grained soil is the water content of the soil

below which it ceases to be plastic. It begins to crumble when rolled into threads

of 3mm dia.

Liquid Limit: The liquid limit is the water content at which it will takes 25 blowsto close the groove over a distance of 13 mm.

Plasticity Index: The plasticity index (PI) is a measure of the plasticity of a soil.The plasticity index is the size of the range of water contents where the soil

exhibits plastic properties. The PI is the difference between the liquid limit and the

plastic limit (PI = LL-PL). Soils with a high PI tend to be clay, those with a lower

PI tend to be silt, and those with a PI of 0 (non-plastic) tend to have little or no silt

or clay.

Modified Proctor Test or Heavy Compaction Test


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Soil at known water content is placed in a specified rammer in to a mould of given

dimensions, subjected to a compactive effort of controlled magnitude and the resulting unit

weight determination. The procedure is repeated for varying Water Content and Dry Unit

Weight.

California Bearing Ratio Test4 days soaked(as per IS:2720(Part 16)- 1985)

The Ratio of the force per unit area to penetrate a soil mass with circular plunger of 50 mm

diameter @ 1.25 mm/min to that required for corresponding penetration of a standard

material.

CBR = [PT / PS] x 100

PT = Corrected unit (or total) test load corresponding to the chosen penetration from the loadpenetration curve (fig. 2 of chapter IS: 2720 (Part 16)-1979 Method of test for soils: Part 16

Laboratory Determination of CBR (first revision) in Compendium of Indian Standards on

Soil Engineering Part 1)


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PS = unit (or total) standard load for the same depth of penetration as for PS taken from table

below.

CBR Apparatus


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Chapter 7:Geotechnical Investigation

In order to obtain information on the physical properties of soil and rock around a site to

design earthworks and foundations for proposed structures and for repair of distress to

earthworks and structures caused by subsurface conditions.

Description Of Field Work

Some soil core samples were collected and these samples were taken to the laboratoryfor tests to obtain various properties of sub soil formation.

Laboratory Testing

The following laboratory tests were carried out on disturbed and undisturbed soil samples

for identification and classification purposes and to obtain the strength and other properties of

the formation.

Grain Size Analysis Natural Moisture Content Atterbergs Limits Specific Gravity:

This is the ratio of the mass of unit volume of soil at a stated temperature to the mass of the

same volume of gas free distilled water at a stated temperature.


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Triaxial Test:A cylindrical specimen of soil encased in an impervious membrane is subjected to a constant

confining pressure and then loaded axially @ 1.25 mm per minute to failure without change

in total water content in the specimen.

The test is limited to specimen in the form of the right cylinder of nominal diameter 38 mm

and height equal to twice the nominal diameter. The ratio of diameter of the specimen to

maximum size of particle in the soil should not be less than 5.

Triaxial Apparatus

One Dimensional Consolidation Test:A test in which the specimen is laterally confined in a ring and is compressed between porous

plates in fully saturated condition. The gradual reduction in volume of soil mass on

application of compressive stress is due to expulsion of water from the pores. The height of

the ring shall not be less than 20mm. with diameter to height ratio of about 3. Further the

specimen height shall be not less than 10 times the maximum particle size.

Consolidation Apparatus


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Chapter 8: Substructure - Piling

8.1 Pile

In this project all the piles were 1000 mm in diameter, 20-25m in length, concrete and

cast-in-situ. These were basically friction piles. For the construction of the pile it should not

take more than 8 hours.

The steps are

Survey Casing punching/driving Boring/drilling Cage lowering Tremmie lowering Flushing Concreting

First the surveyor will give the point for the drilling following the centreline of

formwork. After that a temporary casing is driven but the erection has to be straight so

from the centre two perpendicular lines of 2m is taken together with that spirit level is

used for the straightening of the casing. Constant length of the diagonal is maintained

during the driving of the casing.Boring is done with the help of Hydraulic Rotary piling rig. Temporary steel casing of

required length will be driven. After reaching the founding level the bore will be

thoroughly flushed with fresh bentonite solution. Reinforcement cages will be

prefabricated in suitable length of about 10m. These will be lap welded at site and

lowered in to the bore with the help of mobile crane. On placing the reinforcement

cage, tremmie pipe elements will be assembled and lowered inside the cage. The bore

will be then concreted by tremmie method with a minimum slump of 150mm.

8. 2 Pile cap

After the approval of the pile report, green flag is given to the construction of the pile

cap. The concreting of the pile is done up to the ground level bit it is cut down to cut off level

to get the sound concrete. The reinforcement from the pile is extended further and enters in to

the cap. The reinforcement of the pile cap is made and then concreting. This kind of work is

given to the subcontractor. But before the pile cap a floor of pain concrete (PCC) is done.

Dewatering is also done to expel water from the pit before the concreting.


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Chapter 9: Pavement Analysis and Design

GEOMETRIC DESIGN:

The project corridor lies in plain terrain and passing through highly urbanized areas. As such,

the geometric standards relevant to plain terrain as per IRC: 73-1980 and IRC: 86-1983 have

been adopted.

DESIGN SPEED:

Design speed is the single most important factor that affects the geometric design. It directly

affects the sight distance, horizontal curve, and the length of vertical curves. Since the speed

of vehicles vary with driver, terrain etc, a design speed is adopted for all the geometric

design.

Design speed is defined as the highest continuous speed at which individual vehicles can

travel with safety on the highway when weather conditions are conducive.

HORIZONTAL ALLIGNMENT:

Horizontal alignment is one of the most important features influencing the efficiency and

safety of a highway. Horizontal alignment design involves the understanding on the design

aspects such as design speed and the effect of horizontal curve on the vehicles. The horizontalcurve design elements include design of super elevation, extra widening at horizontal curves,

design of transition curve, and set back distance.

HORIZONTAL CURVES:

The presence of horizontal curve imparts centrifugal force which is a reactive force acting

outward on a vehicle negotiating it. Centrifugal force depends on speed and radius of the

horizontal curve and is counteracted to a certain extent by transverse friction between the tyre


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and pavement surface. On a curved road, this force tends to cause the vehicle to overrun or to

slide outward from the centre of road curvature. For proper design of the curve, an

understanding of the forces acting on a vehicle taking a horizontal curve is necessary.

Various forces acting on the vehicle are illustrated in the figure 1.

Figure 1: Effect of horizontal curve

They are the centrifugal force (P) acting outward, weight of the vehicle (W) acting downward,

and the reaction of the ground on the wheels (Ra and Rb)The centrifugal force and the weight is

assumed to be from the centre of gravity which is at h units above the ground. Let the wheel base

be assumed as b units. The centrifugal force in kg/m2 is given by

where is the weight of the vehicle in kg, is the speed of the vehicle in m/sec , g is the

acceleration due to gravity in m/sec2

and is the radius of the curve in

VERTICAL ALLIGNMENT:

The vertical alignment of a road consists of gradients (straight lines in a vertical plane) and

vertical curves. The vertical alignment is usually drawn as a profile, which is a graph with

elevation as vertical axis and the horizontal distance along the centre line of the road as the

the horizontal axis.

GRADIENT:

Gradient is the rate of rise or fall along the length of the road with respect to the horizontal.

While aligning a highway, the gradient is decided for designing the vertical curve.


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DESIGN TRAFFIC

The method considers traffic in terms of the cumulative number of standard axles (8160 kg)

to be carried by the pavement during the design life. This requires the following information:

1. Initial traffic in terms of CVPD

2. Traffic growth rate during the design life

3. Design life in number of years

4. Vehicle damage factor (VDF)

5. Distribution of commercial traffic over the carriage way.

PAVEMENT THICKNESS DESIGN CHARTS

For the design of pavements to carry traffic in the range of 1 to 10 msa, use chart 1 and for

traffic in the range 10 to 150 msa, use chart 2 of IRC:37 2001. The design curves relate

pavement thickness to the cumulative number of standard axles to be carried over the design

life for different sub-grade CBR values ranging from 2 % to 10 %. The design charts will

give the total thickness of the pavement for the above inputs. The total thickness consists of

granular sub-base, granular base and bituminous surfacing. The individual layers are

designed based on the the recommendations given below and the subsequent tables.

PAVEMENT COMPOSITION

Sub-base

Sub-base materials comprise natural sand, gravel, laterite, brick metal, crushed stone or

combinations thereof meeting the prescribed grading and physical requirements. The sub-base material should have a minimum CBR of 20 % and 30 % for traffic upto 2 msa and

traffic exceeding 2 msa respectively. Sub-base usually consist of granular or WBM and the

thickness should not be less than 150 mm for design traffic less than 10 msa and 200 mm for

design traffic of 1:0 msa and above.

Base

The recommended designs are for unbounded granular bases which comprise conventional

water bound macadam (WBM) or wet mix macadam (WMM) or equivalent confirming to


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MOST specifications. The materials should be of good quality with minimum thickness of

225 mm for traffic up to 2 msa an 150 mm for traffic exceeding 2 msa.

Bituminous surfacing

The surfacing consists of a wearing course or a binder course plus wearing course. The most

commonly used wearing courses are surface dressing, open graded premix carpet, mix seal

surfacing, semi-dense bituminous concrete and bituminous concrete. For binder course,

MOST specifies, it is desirable to use bituminous macadam (BM) for traffic upto o 5 msa and

dense bituminous macadam (DBM) for traffic more than 5 msa.


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Chapter 10: Institutional Framework

FRAMEWORK FOR IMPLEMENTATIONThe project is to be implemented with the intention of decongesting and improving

urban mobility of the Kolkata city. The project would be developed on a public

funded format with partial resources from the state government budget. Construction

should take a period of 18 months.

AUTHORITY FOR APPROVALS/ CLEARANCESThe project would require approvals from the following departments as part of theproject implementation

a) Public Works departmentb) Utilities agencies such as Electricity Boards/ Telephone exchangec) State Pollution control Boardd) Any other approvals, as may be required during implementation

Project Risk Assessment Funding Risk

Construction Risks Cost Overrun Risk Approvals Risk Operation & Maintenance Risks

Present levels of service and proposed improvement1) Present scenario

Kazi Nazrul Islam Avenue (KNIA) or the VIP acts as the main arterial road to

access Kolkata city from Netaji Subhas Chandra Bose International Airport and

National Highways No. 34,35,2 and 6. The existing traffic scenario seriously

impedes smooth urban mobility due to following reasons:-

No separate provision exists for the segregation of through traffic and localtraffic generated from the various cross roads that exist along the project

road.

No separate service road exists for segregation of local slow moving trafficfrom fast moving traffic.

Non existence of adequate pedestrian facilities for smooth passage in themain crossing especially at Kestopur, Baguihati and Jora Mandir.

Unauthorized and haphazard road side parking and scattered movement ofthe pedestrian.


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2) Proposed DevelopmentsTo address the problem of congestion, provide adequate facilities for pedestrian

and facilitate uninterrupted mobility the following measures have been proposed.

(A) Standardize the road cross section of the proposed corridor foraugmentation of the road capacity to cater future vehicular and pedestriantraffic.

Enhance capacity of the corridor by providing standard 6 lanedivided carriageway.

Segregating the local traffic from through traffic and alsomotorized from non-motorized traffic.

Pedestrian facilities need to be planned to minimize thepedestrian conflicts with vehicular traffic.

Parking area needs to be identified especially near the schooland college areas and necessary parking lane has to be

provided.

(B) Proposing Vertical segregation of the through traffic and cross traffic inthe congested stretch and busy intersection to eliminate the conflict among

them.

By providing 4-lane elevated flyover from Kestopur to Jora Mandir via

Baguihati crossing are proposed for through traffic along proposed

corridor. Flyover length will be 1658.5m

(C) Provision for separate Pedestrian subwayProvision for pedestrian subways has been planned at Kestopur, Jora

Mandir and Baguihati with an aim to facilitate smooth and safe pedestrian

crossing and eliminate pedestrian vehicle conflict.

Salient features of pedestrian subways:

a) Location : At Kestopur- Ch. 3.346 KmAt Baguiati- Ch. 4+212 Km

At Jora Mandir Ch. 4+607 Km

b) Vertical clear height : 2.75 mc)

Width of subway : 6.50 m

(D) Road Side Drainage :Longitudinal PCC drain have been provided on the both side of the road

and connected with the existing CD structure for the smooth passage of

storm water.

Major improvements envisaged are as follows:

Reduced travel time (proposed design speed of 70 km/hr) Smooth well maintained pot hole free riding surface Efficient traffic management system including signals, sign boards

and road delineators

Proposed illuminated carriageway


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Uninterrupted movement for pedestrians Overall safety Improved mobility

Documents

Pwd Final Report