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Twenty-eight level crossings closed and replaced with RCC box structures — most of them moved into position beneath track that never stopped carrying trains.
The work
Every level crossing on the network is a place where road and rail meet at the same height, and where the consequences of a mistake are fatal. Eliminating them is the single largest safety programme Indian Railways runs.
A road under bridge replaces the crossing with an RCC box beneath the formation — the road passes under, the gate comes out, and the conflict is gone permanently. The engineering problem is that the railway above cannot stop while you build it.
The box has to arrive under the track inside a block of a few hours. Everything before that is preparation for those hours.
We have delivered twenty-eight of these across four packages for South Central and South Western Railway, in ground ranging from soft soil to solid rock requiring controlled breaking within metres of a running line.
Two methods
Which one you use depends on how much traffic the line carries and how long a block the Railway will sanction. We have executed both, sometimes within the same package.
Method 01
The formation is opened up and the RCC box is cast in situ in the excavation, directly under the track position. Track above is carried on temporary supports while the work proceeds beneath it.
Used at Nagasamudram — 3 tracks, LC 103
Method 02
Box segments are cast on a prepared bed alongside the formation, clear of traffic. Inside a sanctioned block the track is carried on released rails and the segments are jacked and rolled into their final position under the line.
Used at Chakarlapalli & Pandiparthi — LC 72, LC 69
The sequence
This is a box pushing job from first excavation to open road. Scroll through it.
Excavation begins either side of the track while the line stays open. In rock this means controlled breaking within metres of a running railway. The embankment is held with sand-filled bags and the cut is taken down to the box invert level.
RCC box segments are cast on a prepared bed alongside the formation. Reinforcement, shuttering, concreting and curing all happen away from the line, so nothing on the critical path depends on a possession.
Inside the sanctioned block the existing track is dismantled, ballast removed and the rails carried on temporary supports made from released rail. The segments are then jacked and rolled into final position beneath the line. This is the stage that decides the job.
Track is relaid and packed to gauge and the line is handed back. Wing walls, approach roads, retaining walls and drainage follow, and the crossing is closed for good.
Scope of works
Taken from the priced schedules of our railway work orders — these are the real bill items, not a general description.
Casting, supporting and launching of precast RCC box segments to the specified section, including the casting bed and curing.
Jacking and rolling the precast units into final position under the formation, with all thrust and reaction arrangements.
Supporting the track on released rails, and supplying and filling 50 kg polythene bags to hold the formation during the block.
Dismantling and removing existing BG track under block, removing ballast, then relaying and packing the track to gauge.
Reinforcement, cement concreting, structural steel and RCC pipe work, all rated against USSR schedules.
Retaining and wing walls, approach roads, surfacing and drainage arrangements either side of the structure.
Delivered
Sections: Dharmavaram–Pakala · Dharmavaram–Tanakallu · Kalikiri–Damalacheruvu · Kurabalakota–Madanapalle Road · Mulakalacheruvu–Mangalampeta
Crossings: LC 39, 47, 60, 66, 72, 73, 92, 93, 113, 114, 116, 125, 127, 130, 134, 137, 138, 139, 146
Programme: 9 months inclusive of monsoon · accepted 10.10.2017 · completed 16.11.2019
Executed by: Teja–MVVS–KCK (JV)
Section: Bangalore–Dharmavaram (SBC–DMM)
Crossings: LC 103 at Km 163/700–800 · LC 72 · LC 69
Structure: 1 × 5.0 m × 4.5 m RCC box · cut-and-cover across three tracks at LC 103, rolling-in and launching at LC 72 and LC 69
Programme: commenced 25.02.2015 · 4 months + 3 months maintenance
Sections: Vayalpad–Kalikiri and Kalikiri–Piler, Dharmavaram–Pakala
Crossings: LC 104 at Km 158/0–1 · LC 106 at Km 159/2–3 · LC 115 at Km 478/7–8
Accepted: 28.11.2016
Sections: Vayalpad–Kalikiri (Dharmavaram–Pakala) and Pakala–Puthlapattu (Katpadi–Tirupati)
Crossings: LC 102 at Km 154/6–7 · LC 103 at Km 156/3–4 · LC 07 at Km 53/13–15
Accepted: 18.10.2016
On site
Click any photograph to enlarge. Captions describe the stage of work shown and should be checked against site records.
Get in touch
Send us the section, the LC number and the traffic pattern, and we will come back with the method we would use and our record on similar work.