NORTHERN RAILWAYCONSTRUCTION DEPARTMENT(AMBALA DIVISION)FABRICATION OF COMPOSITEWELDED STEEL PLATE GIRDERR.O.B OVER LEVEL CROSSING2nd june to 6th july
NORTHERN RAILWAY Northern Railway, the Jewel Set in the Crown of Indian Railways. Itsheadquarters is in Delhi at New Delhi Railway Station. .Formallyestablished in the year 1952, it remains the largest zone in terms ofroute Kilometres, even after the re-organization of the IndianRailways into 16 zones. Northern Railway now comprises of 5Divisions-Ambala, Delhi, Ferozpur, Lucknow and Moradabad. The Civil Engineering is responsible for the construction andmaintenance of all civil engineering assets, viz all buildings includingstation buildings, residential quarter, hospital, sheds, workshopstructures,goods sheds etc., water supply and sanitaryinstallations, Railway tracks, sidings and all allied structures, Bridgesincluding Road over bridges and Road under bridges.
ROAD OVER BRIDGES The structure crossing the railway track andcarrying road way above is called a Road OverBridge. The portion of this ROB structure withinthe Railways jurisdiction is almost invariablyconstructed and maintained by the Railwayadministration, the remaining portion being left tothe custody of State Govt. or local body as thecase may be. ROBs are used to nullify thehurdles for traffic flow across the railway tracks atlevel crossing.
What is a plate girder bridge? A plate girder bridge is a bridge supported by two ormore plate girders braced together to the required stiffness. Theplate girders are typically I-beams made up fromseparate structural steel plates (rather than rolled as a singlecross-section), which are welded or, in olderbridges, bolted or riveted together to form the vertical web andhorizontal flanges of the beam
Composite steel girders The RCC deck is cast in situ after launching steel girders onsubstructure. Shear connectors are provided on top flange platesof steel beams with channel sections welded all round with sidefillet welds. Shear connectors are required to make cast in situRCC slab and steel girder act together under loadComposite girders consist of the following components: A) RCC deck (Cast in situ at the site of bridge) with shearconnectors embedded in the slab. B) Steel beams with shear connectors welded on top flange(Fabricated in workshop). C) Cross frames D) Bearings
Advantages of using steel for girders Reduced dead loads. More economic foundations. Simpler erection procedures. Shorter execution time. Faster and easier rehabilitation. Durability.
Overview of project work in Ambaladivision (Indian Railway) Construction of composite welded steel plate girder type ROBs is inprogress at Barnala (Punjab) and Budhwala (Punjab) level crossing bythe Indian railway in Ambala division. ROB 92-B at BarnalaThis level crossing is falling between the city Barnala, it joined not onlythe city Barnala on both sides of Railway line but also join the by passapproach to the sangrur Highway. This bridge is being constructed on deposit basis. This level crossing is at km.110/2-3 on Ambala- BathindaRail section. It consist of single span of 46.029 M (overall span) and is inclined at 55degree to the level crossing.
START DATE 6.01.10EXPECTED DATE OF COMPLETION 30.09.2012EXPECTED COST 4.62 croresDESIGN CONSULTANT Structure Consultant Pvt. Ltd.B-1/116 YAMUNA VIHAR DELHI-110053CONTRACTOR M/S MAAN BUILDERSPUNCHKULAOWNER CLIENT NORTHERN RAILWAY
ROB AT BUDHLADA R.O.B in replacement of level crossing No. C-194 atKM.228/814.20 on jakhal-bathinda section near railway station atbudhlada. It consist double span of 22.992m and 36.662m. It will join Bhikhiand Rattia, bhikhi is a town of Punjab and Rattia is a town ofHaryana ( State highway)START DATE 08.7.2011EXPECTED DATE OF COMPLETION 31.7.2012EXPECTED COST 5.62 croresDESIGN CONSULTANT Structure Consultant Pvt. Ltd.B-1/116 YAMUNA VIHAR DELHI-110053CONTRACTOR M/S MAAN BUILDERSPUNCHKULAOWNER CLIENT NORTHERN RAILWAY
Works already been done at the sites All the foundation and pier works at barnala and budhlada wasalready completed. At Barnala CAST-IN -SITU 1m DIA and 16m piles was used as foundation. 2m dia pier with 8.323m height with adjacent centre to centreclearance of 5m was constructed. At Budhlada CAST-IN SITU 1m dia and 16m long piles as foundations. 2m dia pier with 6.5m heigh with adjacent centre to centredistance of 7m was constructed.
Instructions for the construction All RCC work to be done as per IRC-21 C.C mix for substructure M-35 and forsuperstructure M35. All structural steel shall conform to IS: 2062-2006grade ‘B’ All RCC work shall be of concrete mix M-35 andreinforcement bars shall conform to IS: 1786-1985 of minimum grade Fe-415.
Fabrication of steel girdersTESTING OF STEEL PLATE FOR FLAWS Primarily necessary step If internal flaw present in steel plate it can grow due to bendingmoment and shear force.DIGISCAN-322 ultrasonic testingequipment used atBARNALA (PUNJAB)Ultrasonic Testing (UT) uses highfrequency sound energy toconduct examinations and makemeasurements.Ultrasonic inspection can be usedfor flaw detection/evaluation,dimensional measurements,material characterization.
Worker checking for flaws in Steel plate at BarnalaBy Normal beam Inspection.Diagram showing how Testing equipment works and data appears on thescreen.
Cutting of steel plate This is a operation done at the site to get the desiredshape of steel plates being use in the construction ofdeferent components of the structure. Oxy-fuel gascutting is use for this purpose at site. Oxy-fuel cutting are processes that use fuel gasesand oxygen to cut metals. LPG is used as fuel gas at site for the cuttingpurpose.
PUG CUTTING MACHINE Pug cutting machine is automated flame cutting machine which isused for cutting of ferrous metal sheets and plates . An aluminium track is designed over which the machine moves andthe speed of this machine can be adjusted according to thethickness of the cutting metals by electronic control switch.Pug cutting machine over aluminium track being used in Fabrications of 46mspan composite girders of Br. No 92-B at Barnala by Northern Railway.
Being small in size and light weight, the machinecan be easily carried to the worksite and placeddirectly track fixed on the on the plate to be cut. It cuts with rectangular and smooth surface withminimum wastage of steel in cut width.Finished surface after gas cutting
Drilling of holes Prior to welding the plates into the girders required numberof holes of prescribed dimensions has been done at the sitein the plates with the help of drilling machines. These driven holes will be use for connecting adjacent girderwith help of steel plates, bracing and gusset plate. At the site drilling of has been done by two types of drillingmachine:•Portable drilling machine.•Fixed drilling machine.
•Portable type drilling machine have electromagnetic base.•Easy to move.•Generally Use for the drilling in web plate and splice plate.Portable drilling machine use by a person for drilling holes in web plate atbudhlada (Punjab)
Fixed type drilling machine Use for drilling of holes intoflange plate and splice platewhich is use for connectingof adjacent girder. Bottom part of the machineis fixed over the base The upper assembly canrotate over the base anddrilling part of the machinecan move with the help oftrack attached to the upperpart of the machine.
WELDING PROCEDURE During the fabrication, welding of the girder has been done in thedifferent phase. Fillet welding of 8mm unless specify. Procedure is described in the following photographs shown below.Placing of web plate over platform at Barnala
Flange plate is being placed by the side of web plate
Welding of U-shaped plate to theweb and flange plate to keep flangeperpendicular to web atBarnala(punajb)Tack welding
Welding of inclined road to keep web& flange at perpendicular to eachother (Barnala)Hammering to remove the U-shaped plate
Placing of temporary welded girder over inclined platform forwelding with the help of SAW tractor at Barnala
Setup to place web perpendicular to flange plate at Budhlada
SAW tractor at Budhlada Specification of SAW tractor
STIFFENERS Stiffeners are required where factored concentrated loads orreactions exceed the factored Compressive (vertical) resistanceof the plate girder web. Failure due to concentrated loads can be as local buckling of theweb in the region where it joins the flange, or overall buckling ofthe web throughout its depth Transverse stiffeners If a girder has insufficient strength (web local yielding or webcrippling) to support concentrated point loads then a pair oftransverse stiffeners can be added to the web to transfer theconcentrated force to the web.
Bearing Stiffeners: Bearing stiffeners are placed over the end bearings of weldedplate girders and over the intermediate bearings of continuouswelded plate girders. They consist of two or more plates placed on both sides of theweb.Bearingstiffners
Splice plate or cover plate Splice plate or cover plates are used to join the web and flangesof plate girder bridge. These are connected to the steel girdersthrough bolts or fasteners. Bolts or fasteners are used because bolted joint is more flexiblethan welded one. if any bolt fails it can be easily replaced by another one withoutgiving any support. If any girder fails then it can be replaced easily in boltedconnection as compared to the welded one
Splice detail at inner girder near mid Splice detail near support
Splice plate temporary welded to the flanges befor drilling of holes(Barnala)
BEARINGS Bridge bearing is an element of superstructure which provides aninterface between the superstructure and substructure. Thisinterface is vital because superstructure undergoes dimensionalchanges and deformations due to various factors which are listedas follows: Thermal expansion/contraction Elastic deformation under live load Seismic forces Creep and shrinkage of concrete Settlement of supports Longitudinal forces - tractive/ breaking Wind loads.
Details of the bearing to be used at barnalaDetails of the bearing to be used at barnalaDetails of the bearing to be used at barnala
Specifications and instruction for the bearings to be used at Barnala