Downtown Line 2

As the Downtown Line 2 progresses closer to its completion, the public will begin to notice considerable amount of changes to the site landscape on the surface, with the introduction of aesthetics fittings and mechanical/electrical installations to the superstructures. A short consolidated update today tracks the progress of the DTL2 over the first few weeks of 2015, prior to the next quarterly-update which me and WK hope to commence right after CNY.

January 23 - Reinstatement at Newton with the newly opened bus bay

Prison Shaft

3 tunnels remain under C926, which ought to had completed prior to the end of 2014. There have been several complications within the project, with poor project management as one of the contributing factors to the lagging progress. We have a final look at the Prison Shaft where the shield segments of the Bukit Panjang bound TBM has yet to be lowered down. This very machine will be at the face of the breakthrough ceremony at Tampines West to mark the completion of tunnelling works for the Downtown Line in about 4 to 5 months time. 

As of now, only its sister Expo machine has been lowered and in the process of assembling, with the main drive commencing next month. The BP machine should follow suit in March.

Close look of the shield of the BP TBM sitting beneath the gantry crane

Route of the 4 tunnel drives from the Prison Shaft. The highlighted section leftwards to Bedok Reservoir represents the completed bored tunnels, which ends abruptly in the middle after the team stopped updating sometime back in October

3 Tunnels To Go

The 4th final TBM for the Downtown Line broke through the walls of the Tampines Central Station this afternoon. The completed Bukit Panjang Bound tunnel was among two drives executed by GS under C925, which faced numerous setbacks during the early phase of the tunnelling works along the Expo Bound tunnel due to the discrepancy between the excavation progress of the launch shaft and adjacent cut and cover tunnels which were meant to house the backup gantries. Due to the lack of space during the circumstance back then, a muck pump system was proposed by GS with an aim to reduce time loss to the project, however at the expense of a slight increment in cost - which was ultimately approved by the LTA.

The technology brought about great success for GS nonetheless, and today's significant breakthrough marks the end of excavation works for the 10 tunnels they've bored along the Downtown Line projects. 3 tunnels remain within C926 along the Tampines West sector.

DTL3 January Tunnel Chart

Breakthrough of BP bound tunnel at Tampines Central 

Geylang Bahru Cast

Phase 3 of the Downtown Line is beginning to surface upwards with casting works on the substructure the main scope of works at present. We should see the first few superstructures rising by the end of the year. DTL3 is about a year's progress behind stage 2 for a rough comparison. The completed concourse and platform slab at Geylang Bahru is viewed in this update.

Photos courtesy of Hor Kin

Tan Kah Kee Diverts

The 918A project team is currently preparing to stage a road diversion at the Tan Kah Kee station. The diversion is necessary for the remaining columns of the POB on the Bukit Timah bank to be piled and erected. Piling works for the POB columns along the Dunearn bank had just completed last week. Escalators have also been lowered down the main entrance, with BSC targeted by March or April. The roof slab can also be seen at the former launch shaft. 

The construction team will continue working through the weather, round the clock for the next 48 hours to complete the diversion by the weekend. 

Casting works on going along the realignment

Render of the constructed columns on the Bukit Timah bank that the diversion is catering for

Retrieval of S693

Following its breakthrough 2 weeks ago, the cutterhead of the final Herrenknecht TBM was lifted out of the retrieval shaft at Tai Seng Facility Building (junction of Airport Road & Bartley Road East) a day before New Year's Eve. This is the last TBM for the Downtown Line to be retrieved, with the shields of the remaining 4 machines to be abandoned in-situ upon docking.

Cutterhead being lifted up - viewed from the Bartley Viaduct