October Tunnel Progress

TEL1/2 Tunnel Chart, October 2015

Contract T206

Excavation of the Changi Bound tunnel by S-893 commenced at the LS2 last month. 15 rings have been erected as of October 12, and 54 rings built as of October 25 (9% completed, ~ 3 rings/day). At the present advance rate, the estimated breakthrough for S-893 is slated around June 2016.

S-894 will commence excavation on the Woodlands Bound tunnel soon.

The T206 project utilizes the steel fibre reinforced concrete (SFRC) segments, a special type of tunnel lining which uses less steel, however is more durable and crack resistant. The segments were previously trialed on the C933 Downtown Line project and the LTA has extended the use of these segments along a 10km stretch of tunnels under the T206 & T207 projects of the Thomson-East Coast Line. The SFRC lining consists of 7+1 segments instead of the usual 5+1. The tunnel lining segments for T206 are currently being supplied by Kimlun in Malaysia.

Progress of S-893 on the Changi Bound tunnel between LS2 to Woodlands (October 24)

Gardens By The Bay D-walls (IV)

Works on the diaphragm wall at the Gardens By The Bay station is nearing completion and excavation works should commence by early next year. A portion of the launch shaft has been partially excavated and shored in preparations for the decking to accommodate the upcoming diversion of Marina Gardens Drive.

The GBME retrieval shaft site across the channel has been hoarded up and a grab is on site to construct the d-wall panels. Ground improvement works continue along the stretch of tunnel route near Entrance C.

Preparations to divert Marina Gardens Drive

Piling at Marina South (II)

Piling works have started at the cut and cover tunnel where the deep soil mixing activities have presumably been completed. Following the realignment of Central Boulevard, the DCM rigs have been re-positioned towards the north over the bored tunnel alignment for the ground improvement works ahead of the TBM drive. Piling and ground improvement works continue at the Marina South station.