Launching of Br. 21

8/8/2019 Launching of Br. 21

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LAUNCHING OF A 250LAUNCHING OF A 250ft.ft.

OPEN WEB THROUGH STEELOPEN WEB THROUGH STEELGIRDER AT BR. NO. 21GIRDER AT BR. NO. 21


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LAUNCHING SCHEMELAUNCHING SCHEME


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CRITICAL STAGES EXAMINEDCRITICAL STAGES EXAMINED CH SPAN AT MAX. CANTILEVERCH SPAN AT MAX. CANTILEVER

REVERSAL OF STRESSES IN CH SPANREVERSAL OF STRESSES IN CH SPAN

DIAGONALSDIAGONALS

LIFTING OF CH SPAN AT OTHER ENDLIFTING OF CH SPAN AT OTHER END

STRESSES IN FLOOR MEMBERS OF CH SPANSTRESSES IN FLOOR MEMBERS OF CH SPAN

WITH CANTILEDGEWITH CANTILEDGE

LINK MEMBER AT CENTRELINK MEMBER AT CENTRE

LINK MEMBER CONNECTIONSLINK MEMBER CONNECTIONS

REVERSAL OF STRESSES IN MAIN MEMBERREVERSAL OF STRESSES IN MAIN MEMBER

STRESSES IN GRILLAGE SUPPORTSTRESSES IN GRILLAGE SUPPORT

THEORATICAL DEFLECTIONS CALCULATEDTHEORATICAL DEFLECTIONS CALCULATED

AND COMPARED WITH ACTUAL DEFLECTIONAND COMPARED WITH ACTUAL DEFLECTION

AT VARIOUS STAGES OF LAUNCHINGAT VARIOUS STAGES OF LAUNCHING


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BRIDGE NO. 21BRIDGE NO. 21


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DESIGN OF LINK MEMBERDESIGN OF LINK MEMBER


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PRACTICE TILL NOWPRACTICE TILL NOW

SINCE CENTRE TO CENTRE DISTANCE OF CHSINCE CENTRE TO CENTRE DISTANCE OF CHSPAN IS LESS THAN STD. 250 SPAN GIRDER,SPAN IS LESS THAN STD. 250 SPAN GIRDER,TO FACILITATE LINKING, ALL CROSS GIRDERS,TO FACILITATE LINKING, ALL CROSS GIRDERS,TOP & BOTTOM BRACINGS WERE BEINGTOP & BOTTOM BRACINGS WERE BEING

FABRICATED FOR ONE TIME USEFABRICATED FOR ONE TIME USE

CONCEPT PROPOSEDCONCEPT PROPOSED

USE SAME CH SPAN CROSS GIRDERS, TOP &USE SAME CH SPAN CROSS GIRDERS, TOP &

BOTTOM BRACINGS AND TO DESIGN NEW LINKBOTTOM BRACINGS AND TO DESIGN NEW LINKMEMBERS TO CONNECT TWO GRDERS WITHMEMBERS TO CONNECT TWO GRDERS WITHDIFFERENT C/C DISTANCEDIFFERENT C/C DISTANCE


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ELEVATION OF LINK MEMBERELEVATION OF LINK MEMBER


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TOP PLAN OF LINK MEMBERTOP PLAN OF LINK MEMBER


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VIEW OF LINK MEMBERVIEW OF LINK MEMBER

LINK MEMBAR

CH SPAN

MAIN GIRDER


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REPLACEMENT OF BED BLOCKSREPLACEMENT OF BED BLOCKS


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SIDE SLEWINGSIDE SLEWING


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ARRANGEMET FOR SIDE SLEWINGARRANGEMET FOR SIDE SLEWING


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ADVANTAGES WITH THIS SCHEMEADVANTAGES WITH THIS SCHEME

ECONOMICAL BY ABOUT 40 LAKHSECONOMICAL BY ABOUT 40 LAKHS

REDUCTION IN FABRICATION WORK OFREDUCTION IN FABRICATION WORK OFTEMP. CROSS GIRDERS, TOP& BOTTOMTEMP. CROSS GIRDERS, TOP& BOTTOMBRACINGSBRACINGS

SAVING IN TIMESAVING IN TIME


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A FEW SITE PHOTOGRAPHSA FEW SITE PHOTOGRAPHS


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EXECUTING THE WORK AT SITEEXECUTING THE WORK AT SITE

AFTER LAUNCHING NOSE COMPLETELY THEAFTER LAUNCHING NOSE COMPLETELY THE

CANTELEDGE WEIGHT WERE REMOVED.CANTELEDGE WEIGHT WERE REMOVED.

MAJOR WORK OF THIS MEGNITITUDE WASMAJOR WORK OF THIS MEGNITITUDE WASLAST DONE DEPATMENTALY SOME 32 YEARSLAST DONE DEPATMENTALY SOME 32 YEARS

BACK.BACK. DUE TO RESTRICTED AREA AVAILABLE AT SITEDUE TO RESTRICTED AREA AVAILABLE AT SITE

IT WAS DECIDED TO FIRST ASSEMBLE CH SPANIT WAS DECIDED TO FIRST ASSEMBLE CH SPANPANNEL BY PANNEL AND LAUNCH THE SAMEPANNEL BY PANNEL AND LAUNCH THE SAME

TO INCREASE THE ASSEMBLING AREA CC CRIBTO INCREASE THE ASSEMBLING AREA CC CRIBSATGING WAS PROVIDED ON EITHER SIDE OFSATGING WAS PROVIDED ON EITHER SIDE OFTHE CANAL BANK.THE CANAL BANK.


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ContdContd

GRILLAGE OF ISMB WAS PROVIDED ON TOP OFGRILLAGE OF ISMB WAS PROVIDED ON TOP OF

CRIB STAGING TO COUNTER THE FRICTIONALCRIB STAGING TO COUNTER THE FRICTIONALFORCE OF LAUNCHING AND CANTILEVER LOADFORCE OF LAUNCHING AND CANTILEVER LOADOF LAUNCHING NOSEOF LAUNCHING NOSE

DURING ASSEMBLING/LAUNCHING OF L/NOSE,DURING ASSEMBLING/LAUNCHING OF L/NOSE,

THE MAIN SPAN WAS ASSEMBLED CONFIRMINGTHE MAIN SPAN WAS ASSEMBLED CONFIRMINGTO B1TO B1--2001 ON ONE SIDE.2001 ON ONE SIDE.

CANTELEDGE WEIGHT OF 140 MT WAS PLACEDCANTELEDGE WEIGHT OF 140 MT WAS PLACEDON THE REAR OF LAUNCHING NOSE DURINGON THE REAR OF LAUNCHING NOSE DURINGFINAL STAGE OF LAUNCHING.FINAL STAGE OF LAUNCHING.

DEFLECTION OF LAUNCHING NOSE WASDEFLECTION OF LAUNCHING NOSE WASRECORDED REGULARLY AFTER LAUNCHING FORRECORDED REGULARLY AFTER LAUNCHING FOR

OBSERVING THE BEHAVIOUR.OBSERVING THE BEHAVIOUR.


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ContdContd

MAIN SPAN ALREADY ASSEBLED ON THE SIDEMAIN SPAN ALREADY ASSEBLED ON THE SIDE

WAS BROUGHT INLINE OF LAUNCHING NOSE.WAS BROUGHT INLINE OF LAUNCHING NOSE. MAIN SPAN CONNECTED WITH THE NOSE WITHMAIN SPAN CONNECTED WITH THE NOSE WITH

THE HELP OF SPECIALLY DESIGNED LINKTHE HELP OF SPECIALLY DESIGNED LINKMEMBER.MEMBER.

ROLLER ARRANGEMENT WAS PROVIDED UNDERROLLER ARRANGEMENT WAS PROVIDED UNDERTHE STRINGER OF MAIN SPAN FOR ROLLING OFTHE STRINGER OF MAIN SPAN FOR ROLLING OFMAIN SPAN.MAIN SPAN.

AFTER THE MAIN SPAN WAS LAUNCHEDAFTER THE MAIN SPAN WAS LAUNCHEDCOMPLETELY THE SAME WAS DELINKED WITHCOMPLETELY THE SAME WAS DELINKED WITHTHE LAUNCHING NOSE.THE LAUNCHING NOSE.


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ContdContd

BOTTOM LATERAL BRACEINGS WERE PROVIDEDBOTTOM LATERAL BRACEINGS WERE PROVIDED

RAILS WITH STEEL CHANNEL SLEEPER WERERAILS WITH STEEL CHANNEL SLEEPER WEREFITTEDFITTED

MAIN SPAN LOWERED TO REQUIRED LEVEL TOMAIN SPAN LOWERED TO REQUIRED LEVEL TO

KEEP THE RL OF NEW AND OLD SPAN SAME.KEEP THE RL OF NEW AND OLD SPAN SAME. FOR PULLING OUT THE OLD GIRDER ANDFOR PULLING OUT THE OLD GIRDER AND

ROLLING IN THE NEW GIRDER ROLLINGROLLING IN THE NEW GIRDER ROLLINGARRANGEMENT UNDER THE MAIN CROSSARRANGEMENT UNDER THE MAIN CROSS

GIRDER AT BEARING POINT, PULLING &GIRDER AT BEARING POINT, PULLING &RESTRAINING WINCHES ETC. WERE PROVIDED.RESTRAINING WINCHES ETC. WERE PROVIDED.


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ContdContd

THE TAKING OUT OF OLD GIRDER ANDTHE TAKING OUT OF OLD GIRDER ANDINSERTING OF NEW GIRDER WAS DONEINSERTING OF NEW GIRDER WAS DONESUCCESSFULLY IN A TRAFFIC BLOCK OF TENSUCCESSFULLY IN A TRAFFIC BLOCK OF TENHOURS AFTER PLANNING THE SAMEHOURS AFTER PLANNING THE SAME

MATECULOUSLY.MATECULOUSLY.

Documents

Launching of Br. 21