Central Railway found a way to overcome flooding of tracks at Masjid railway station, which is at a lower level than the ground level. It was decided to lay a 1000 mm diameter RCC pipe by micro-tunnelling method without disturbing rail movement, as this method has given very good results at Sandhurst Road station area, where 1800mm diameter RCC pipe was laid for 425-meter length connecting west side to east side across railway tracks.
A meeting was held in coordination with Municipal Commissioner and Divisional Railway Manager in February 2021 where it was decided to go ahead with the project to prevent flooding of tracks during monsoon. The situation worsens during high intensity rainfall coupled with high tide, inadequate capacity of culvert, lower storm water drainage network carrying capacity.
This project which covers both railway area and municipal area, started at the end of April 2021 in co-ordination with railways and the work in railway area completed recently. Work of connection of newly laid RCC pipe with MCGM network is in progress by MCGM and the same is likely to be completed by this month-end. Storm water will be bypassed through this newly laid RCC pipe culvert once the whole project is completed which will prevent storm water coming inside railway premises and eliminate flooding of tracks. The similar kind of work of micro-tunnelling in co-ordination with civic authorities have already been successfully completed at Sandhurst road station and Dadar-Parel area during monsoon period this year.
Central Railway, General Manager, Anil Kumar Lahoti said that Micro-tunnelling is a proven technology widely adopted and recently tried, tested and executed at the Sandhurst Road railway station area. The Railway portion micro-tunnelling work at Masjid railway station has been completed in a very short period and this will help to prevent waterlogging during monsoon at Masjid railway station.
Activities carried out:
• Detailed topographical survey to fix the level of pipe.
• Survey to find out underground obstruction.
• Geological survey by taking bore logs.
• Construction of jacking and receiving pit.
• Aligning and setting up a micro- tunnelling boring machine.
• Casting and testing of 1000mm dia RCC jacking standard pipes.
• Laying of RCC jacking pipe by micro tunnelling boring machine.
During execution of work, an old stone British-era masonry duct was encountered in alignment of the micro tunnelling boring path. Due to hollow stone masonry duct, feed water not coming back as slurry restricting the removal of bored muck through slurry line to slurry tank. This prevented bored muck in the form of crushed stone pieces getting jammed in a slurry line frequently.
There was a very hard rock encountered in the same alignment. To counter it and to lower the time limit to finish the project, a special machinery of horizontal directional drilling was deployed to weaken the rock mass by making various sizes of holes in hard rock mass and ultimately enlarging them to complete periphery to speed up the work being done.