The National High Speed Rail Corporation Limited (NHSRCL) has initiated the track laying works for Mumbai-Ahmedabad High Speed Rail corridor. The track laying activity begins at Surat HSR station. The NHSRCL is constructing the first Reinforced Concrete (RC) track bed as used in Japanese Shinkansen. This is for the first time that the railway is installing a J-slab ballastless track system in the country.
What is the J-slab ballastless track system?
The J-slab ballastless track system comprises a pre-cast track slab over which fastening devices and rails are fitted. This slab rests on the RC track bed. This slab has a thickness of around 300 mm and constructed in-situ (at site) for individual UP and Down track lines on viaduct top. The width of the RC track bed is 2420 mm.
The RC anchors are provided to avoid any longitudinal and lateral restraint to the track slab. The size of RC anchor is 520 mm diameter and height is 260 mm. These are constructed at 5 m (approx) centre to centre. In RC anchor, a reference pin is installed for achieving desired alignment (both horizontal and vertical). This is suitable for train operation at 320 kmph.
Contract for track laying works:-
For the Gujarat portion, the contracts for the track works have been awarded. Currently, the material procurement for track works is in advance stage. Japan has already handed over more than 14000 MT of JIS rails and 50 moulds for casting track slabs.
Manufacturing of track slabs in MAHSR corridor:-
The track slabs to be laid in the MAHSR corridor will be manufactured in two dedicated factories. These factories are equipped with the most sophisticated and state of the art technologies and infrastructure to produce precise slabs for HSR track construction.
For track works, the NHSRCL will use special construction machinery such as rail feeder cars, slab laying cars and CAM (Cement Asphalt Mortar) laying cars.