Apsara Border

  • View
    215

  • Download
    0

Embed Size (px)

Text of Apsara Border

  • 7/31/2019 Apsara Border

    1/15

    136 NBM&CW SEPTEMBER 2011

    Grade Separator

    Challenges Faced

    in Planning, Design& Construction of

    Grade SeparatorNear Apsara Border,

    Delhi

    Alok Bhowmick,

    Managing Director, B&S

    Engineering Consultants Pvt. Ltd.,

    Noida

    The paper describes the salient features of design

    and construction of one of the most complex three

    level grade separators ever constructed in the city of

    Delhi. The Grade Separator comprises the following

    major structural components:

    A 6-lane flyover at Apsara Border along the GT

    Road

    2 Nos. 2 lane Underpasses along Road No. 56

    and Road No. 62

    2 Nos. RUBs constructed under extremelychallenging conditions by using box pushing

    technique

    2 Nos. of Foot Over Bridges across Road No. 56

    and Road No. 62

    Widening of existing bridge over Major Drain &

    Allied Works

    This is possibly the first project in India where

    contiguous piles in combination with prestressed

    horizontal anchors have been successfully used for

    supporting the existing ROB approach close to the

    proposed Underpass. This is also the grade separator

    with longest total length of Underpass constructed inDelhi (total length 1666m). The paper highlights the

    salient technical features of the project components

    including the design and construction issues.

  • 7/31/2019 Apsara Border

    2/15

    140 NBM&CW SEPTEMBER 2011

    Grade Separator

    IntroductionRapid development and urbanization

    of Delhi and surrounding areas

    coupled with the high average

    income of the populace (with large

    standard deviation) has largely

    eclipsed socio-cultural traits that

    used to represent Delhi until a few

    years after independence. Traffic

    congestion, longer travel times and

    high levels of air pollution are just

    some of the growing problems

    faced by the citys residents. Rising

    incomes and a burgeoning middle

    class has seen an increase in

    private vehicles in the past two

    decades, particularly because the

    public transport system has notkept pace. Delhi has nearly 4.5

    million vehicles, which is more than

    that in the three other major Indian

    cities of Mumbai, Calcutta and

    Chennai put together. The growth

    in the number of vehicles has had

    a knock on effect on the roads of

    the city. Traffic congestion, longer

    travel times and high levels of air

    pollution are just some of the

    problems faced by the citys

    residents. Coupled with the above,

    there was tremendous pressure to

    improve infrastructures in the urban

    areas in general for the

    Commonwealth Games of October

    2010, which led to the construction

    of this grade separator which was

    long overdue at this intersection in

    any case.

    Need for the ProjectThe need for a grade separator at

    the Seemapuri Border near Apsara

    Talkies was felt for more than two

    decades. Long queues at the

    Intersection, frequent jams with

    traffic stuck for hours were a

    common sight at this intersection.

    Public Works Department, Govt. of

    Delhi had initiated this ambitious

    project in the year 2006, with the

    objective to increase road

    connectivity between Delhi and U.P,

    between Anand Vihar to Shahdaraand between Ghaziabad to

    Maharana Pratap ISBT, Anand Vihar.

    Feasibility study for the project was

    carried out based on which, a six

    lane flyover is envisaged along the

    G T Road at this intersection

    connecting Delhi & U.P and two

    underpasses of 2 lane each are

    envisaged along Road No. 56 (one

    on either side of existing ROB) to

    connect Anand Vihar with Dilshad

    Garden.

    Fig. 01 shows the key plan

    showing alignment of Flyover,

    Underpasses and location of Foot

    Over Bridge. Part of the six lane

    flyover falls in U.P side, for which

    PWD got the working permission

    from UP government. Cost of the

    flyover however is borne by the Govt.

    of Delhi.

    Project Award dates

    Approval for this project from

    Technical Committee of DDA was

    obtained in September 2006. DUAC

    approval was obtained in July 2007.

    The administrative approval for the

    project was obtained on 9 th June

    2008 for an amount of 226.47

    crores.

    The construction contract for

    this project was awarded to M/S

    AFCONS Infrastructure Limited,

    Mumbai for an amount of `180.2crores. The construction period was

    allocated as 21 months. The salient

    dates for the project are as under :

    Date of Commencement of Work

    : 10th September 2008

    Stipulated Date of Completion

    : 9th June 2010

    Flyover opened to traffic on

    : 24th April 2010

    1st Underpass opened to traffic

    : 31st October 2010

    2nd Underpass opened to traffic

    : 5th January 2011

    Photo P1 shows the completed

    Grade Separator in Google Map.

    Photo 1: Completed Grade Separator in GOOGLE map

  • 7/31/2019 Apsara Border

    3/15

    142 NBM&CW SEPTEMBER 2011

    Grade Separator

    Salient Features &

    Components of the

    Grade SeparatorFlyover along G T RoadThe 6 lanes flyover with divided

    carriageways of 9m width (reduced

    3 lanes) is constructed along the G

    T Road. The total length of theflyover is 646m with length of the

    stilted portion of 340m and balance

    306m in solid fill with Reinforced

    Earth Walls. The overall width of

    the flyover including median is

    20.2m.

    The span arrangement for the

    stilted part of flyover comprises 3

    modules of continuous span units.

    The central module comprise 4

    spans of span lengths

    40m+50m+50m+40m, totaling a

    length of 180m, while the endmodules on either side of the

    central module comprise 2 span

    continuous structure of lengths

    40m+40m each. Expansion joints

    are provided at Abutments and at 2

    intermediate sections, 80m away

    from the abutments. Fig. 02 shows

    the General Arrangement of the

    Flyover.

    The Superstructure comprises

    a steel concrete composite plate

    girder with in-situ RCC deck slab.

    The girders are supported on

    metallic bearings. The overall depth

    of the superstructure deck is kept

    at 1.925m. 4 plate girders are

    provided transversely at a spacing

    of 2.5m for supporting each of the

    3 lane carriageway. The depth of

    plate girders are kept as 1.7m. High

    strength steel of grade Fe540B

    conforming to IS:2062-2006 has

    been used. The deck slab of

    225mm thick is provided in M35

    concrete on top of plate girders.

    For the stilted portion, the two

    carriageways are structurally

    isolated and a longitudinal clear

    gap of 200mm is provided at the

    centerline of the median along the

    entire length.

    The bearing arrangement

    comprises series of Metallic Free

    POT cum PTFE bearings underouter girders, Guided Bearings

    under internal girders at Free /

    Expansion joint piers and Fixed

    Bearings under internal girders of

    fixed piers. The combination of

    these types of bearings ensure

    transfer of vertical loads and lateral

    loads from Superstructure to the

    foundation, through substructure.

    Fig. 03 shows the bearing

    arrangement for a typical

    carriageway of this project.

    RCC single circular pier of 2.0m

    diameter have been provided under

    each carriageway for all piers and

    abutments, except fixed piers P4, in

    which case pier diameter of 2.75m

    has been provided. Pier cap is

    cantilever type in all cases. Seismic

    stoppers / arrestors are provided in

    the transverse direction to arrest

    the possible dislodgement of

    Superstructure in the transverse

    direction under earthquake loads.

    Fig. 04 to Fig. 08 shows the typical

    details of various components of

    the Flyover.

    The foundation sub-strata as

    per the Geotechnical Report

    comprise road fill or loose filled up

    soil upto a depth of about 2.5m,

    followed by silty fine sand / fine

    sand layers upto 10-13m depthunderlain by very dense sandy

    strata upto the explored depth. Total

    of 10 number of bore holes have

    been taken at the project site to

    establish the geotechnical

    properties for foundation design.

    Bored cast-in-situ piles of

    diameter 1.2m have been used for

    supporting the stilted portion of

    flyover. Total of 108 numbers of

    piles have been provided for the

    flyover. Pile capacity considered is

    287 Tonnes for a length of 30m

    below pile cap bottom. The safe

    load capacity has been confirmed

    by conducting initial pile load tests

    as well as routine load tests on

    working piles. Number of piles

    provided under each foundation (for

    each carriageway) is as under :

    Abutments A1 & A2 : 4 nos.

    Piers P1, P3, P5 & P7 : 6 nos.

    Piers P2 & P6 : 5 nos.

    Pier P4 : 12 nos.

  • 7/31/2019 Apsara Border

    4/15

    144 NBM&CW SEPTEMBER 2011

    Grade Separator

    Photo P2 & P3 shows the

    completed Flyover in service.

    Underpasses along Road

    No. 56 & Road No. 62Two Vehicular Underpasses

    are provided alongside of

    Road No. 56 and Road No.

    62 connecting Dilshad Garden

    and Anand Vih

Search related