Civil Team 2 - Completion

This consolidated update showcases the completion of the 5 stations from Rochor to Botanic Gardens under the Downtown Line 2's civil team 2 project, excluding Tan Kah Kee Station.

Rochor Station

Entrance B

Botanic Gardens Station

The Land Transport Authority held a ministerial tour on the Downtown Line 2 between Little India, Botanic Gardens and the Gali Batu Depot yesterday for the announcement of the line's impending opening on December 27, as well as to provide an update on the rail report.

The new line, together with the existing operational stage 1, is expected to operate freely over the festive holidays for the first week upon opening.

The twin escalators at the platform of Botanic Gardens are one of the longest along the line

Gardens Reinstatement

The C919 project is also wrapping up works at the Botanic Gardens station with majority of the entrance's architectural works completed. Landscaping and the re-opening of the widened slip road will pave the way for a complete reinstatement by August.

Completed entrance at Botanic Gardens

Stevens Reinstates

Reinstatement works are almost completed at the Stevens Station. The 919 team have completed majority of the architectural works on the superstructure, and are preparing to reinstate Robin Walk as well as the slip road turn to Stevens Road.

Reinstatement on the surface of Stevens Station

Stevens Superstructure

Upon completion of hacking of the temporary diaphragm wall, the slip road at Stevens have been permanently realigned back in Christmas last year. The remaining structure along exterior face of the entrance has been cast. M&E works are currently underway within the superstructure. The new drain culvert that will run parallel to the entrance is being formed too. Architectural works should commence around the middle of the year.

Due to the tight space constraint at the site, reinstatement works which includes the reopening of Robin Walk as well as the permanent bus bay is only expected to take place nearer to the completion of the project, in the later part of the year.

Photos in this update were taken on March 13.

Downtown Line entrance to the Stevens Station

Gardens Superstructures

The steel roof of the Botanic Gardens station entrance was assembled back in Christmas last year, shortly after the previous update. Steel L-shaped fixtures for the sheltered linkways leading from the entrance, as well as the drop off bay have also been constructed over the past month. Both ventilation building and cooling tower have been painted brown, as believed to be the station's themed livery. The cooling tower has been cladded as well.

Reinstatement works have also commenced, with the footpath alongside the future widened road constructed. The road should be widened by the 3rd quarter.

March 16 - Aerial view of the 3 completed superstructures

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

Garden's Surface

Back on the surface, the final touches on casting works of the concrete superstructures are almost completed. The ventilation unit has arrived and positioned inside the cooling tower. Steel frame segments are also seen beside the entrance, a strong indication of the impending works of covering up the entrance.

Botanic Gardens worksite

Stevens Hacks D-wall

Following the final road diversion 2 months back, the project team has completed the demolishment of the temporary Diaphragm Wall beneath Bukit Timah Road. The temporary road deck has been removed and the team will begin to resurface the permanent road above the station. The road should be reinstated early next year. Architectural works on the station exit should commence around the same time.

Along Stevens Road, the T216 project of the Thomson Line is also working together with C919 Sembawang as both teams stage their traffic diversions simultaneously.

D-wall has been hacked beneath the road and earthworks for reinstatement is taking place

Superstructure of Stevens Station

Twin traffic diversions taking place between C919 and T216

Linking the Gardens

Our 4th Quarter updates for DTL2 begins here at Botanic Gardens. Sembawang has been behind project timeline for the C919 project which translates into a seeming stagnation of progress on the superstructures. The site boundaries have recently been expanded towards the west to allow for a larger space for the construction of the vent shaft. A replacement walkway has been created over the grass patch near the underpass divider.

Formwork is almost completed on the superstructures' roof with concrete gaining strength. Architectural works should commence by December. Interior works have also intensified along the Circle Line station as the final stage of A&A works of demolishing a section of the existing plant room and false walls that will form the eventual underground paid linkage between both lines.

Hoardings within the paid area of the Circle Line concourse plastered this month

Bukit Timah Road Realigns

Many changes have taken place across the various DTL2 sites over the last couple of days. This dedicated post would consolidate all the new developments.

Newton
One of the most significant milestone in the project timeline, C920 has completed its last phase of traffic diversion at the Newton site - the first DTL2 project to have done so. The slip road has been reconstructed over the backfilled launch shaft ahead of the projected Q4 2014 timeframe indicated on the road signages. Having diverted back the road, land is freed up to construct up the remaining segments of the entrance. Steel frames for the future walkway ramp has begun to form.

Reinstated Bukit Timah Road. Do note that the bus stop location is temporary.

Here is the recently completed escape shaft at Ferrell Residences. The site is temporary hoarded up.

Escape Shaft

Stevens
C919 will be carrying out one final traffic diversion at Stevens. This is for the hacking of the d-wall located below the existing road. Unlike the initial diversion back in 2011, the presence of the station superstructure now imposes an incredible site constraint. The road has been positioned and surfaced right up to the edge of the structure. The diversion will be carried out this Thursday.

Diversion works

Managed to get a glimpse of the entrance escalators being lowered down prior to road diversion preps as I was walking by the week before. A rare sighting.

September 12

September 12 - Escalator segment going down the entrance

Tan Kah Kee
Following the achievement of BSC for the expo bound tunnel to BTN, the final standalone gantry crane for DTL2 has been dismantled at the TKK launch shaft. Backfilling of the shaft will begin at once.

More photos below.

Botanic Gardens

Alongside Stevens, the superstructures at Botanic Gardens have risen quickly within the past 4 months. The cooling tower and lift shaft is completed. The entrance structure is being worked on.

Drawn by Seloloving, Skyscrapercity

Aerial view of the entire station

A render of how the Botanic Gardens station exit will appear when the station is completed.

Stevens

The magnificent structure at Stevens has started taking shape since our last update in May. The exit structure will be integrated with the cooling tower, vent shafts, taxi stand and bus stop. This will be the first stacked station to not feature any escalators or stairs within the paid area. 

Under the DTL project, Stevens will initially open with its main entrance E along Bukit Timah Road. The remaining entrances will be completed under the TSL project in 2021. Drawn by Seloloving, Skyscrapercity

A render of what the Stevens station exit will look like once completed.

The entire station layout is extremely complicated as the architecture maximizes the amount of end to end connections between the various exits, concourse and platform levels. Below is a simplified layout.

B1 - TSL Concourse

B2 - DTL Expo Bound Platform/ Future TSL mezz & canal linkage to Entrance C and D

B3 - DTL mezzanine/ Future TSL platforms

B4 - DTL BP Bound Platform

A rough guide of the Stevens station cross section, done by y2koh, Skyscrapercity.
*B2: canal linkage to Entrance C and D is not directly linked to DTL platform/concourse
*B3: DTL mezzanine & Future TSL platforms will not be directly linked

There will be 2 lift shafts. The south shaft will connect the surface to both unpaid levels. The north shaft will connect the surface to an initial unpaid areas at the north end of both platforms. These unpaid areas will eventually be converted to paid areas for the linkage between the TSL transfer levels, and the faregates will be relocated to the street level.

Additions to the DTL structure under the Thomson Line project:

• A further 2 lifts will be constructed at the roof of the DTL station in the future to link the TSL concourse to the surface of entrance E. (Ground level to B1) 
• A third lift will be constructed directly below the Wayang Satu Flyover to link the TSL Concourse, canal subway and DTL mezzanine. (B1, B2 and B3)

Vent Shaft 2 taking shape at the corner of the station. A future taxi bay will be located here when Robin Walk reopens

S602 Breakthroughs, BP Bound Completes

Completion of all bored tunnels within DTL2

At last, the final TBM (S602) has docked into Sixth Avenue Station, concluding 36 months of tunnelling works for the entire Downtown Line 2 when S548 was first launched at Beauty World on 8 June 2011. McConnell Dowell, which coordinated this final TBM docking at Sixth Avenue, is the same contractor which facilitated the inaugural TBM launching at Beauty World 3 years ago. CP1&2 has been excavated and supported, while the last cross passage 3 is currently being mined.

We'd like to acknowledge Herrenknecht, Kawasaki and Hitachi Zosen, the manufacturers for the 19 TBMs along Stage 2. Herrenknecht AG has a renowned history in producing the quality S-number TBMs of various sizes and uses since 1975. The local demand for their machines have steadily grown over the years since the successful implementation of S134 and S135 between Farrer Park and Boon Keng stations along the North East Line. A further 9 machines were procured to construct the southern half of the bored tunnels for the Circle Line. 22 machines had been ordered throughout DTL2 and DTL3, and more will come with the increasing demand of upcoming metro lines.

Kawasaki from Japan delivered 5 machines that were ordered under GS and SK for Contract 913 and 915. Most of their machines used in Singapore are of the slurry type, with a few currently involved in the SP cable tunnel project. Hitachi Zosen supplied STEC 4 Earth Pressure Balance Machines under C920.

These sophisticated machinery would not have been able to operate without the hundreds of men working beneath the surface under immense pressure and poor ventilation. A very big thank you to the tunnelling team from all nationality.

Below is a flashback of the earlier few TBM launches along the stage.

Inaugural launch at Beauty World

Day 10, Stevens

Stevens station. The entrance pit has just recently been formed and concreted. From now, the station will progressively take shape at the surface following the construction of stairs and subsequent installation of escalators. Below is a photo timeline of the construction progress taken over the last 3 years.

Piling and Trench Cutting works mid 2011

Excavation works started to commence early 2012 following the drive of the remaining king posts

Late 2012. Gantry cranes were brought in to facilitate top-down movements due to site constraints.

Overview of Stevens Station - as it is now in May 2014

Next Station, Botanic Gardens

A preview to the final and deepest interchange along DTL2.

Satellite image of BTN on Apr 24

DTL Concourse - Platform Twin Escalators

Stage 2 update January 2014

A month has passed since we entered into 2014 and this provides a good chance to look back at the progress over the stage 2 stations thus far. On the whole, the stations are progressing swiftly towards completion in 2016. It was reported in December that "Several stations have achieved basic structural completion for electrical and mechanical installation works to begin and this will be progressively achieved at all 12 stations by mid-2014". It is notable that most station structures are taking shape decently, with several showing signs of reaching the final levels where the entrances and exits pop up.

Stevens and Newton

A&A works have commenced at the concourse of Newton station.

Sembawang is also dismantling the west gantry crane at Stevens after about 1.5 years of operation. The roof slab is completed and they're freeing up the site while they can. The east gantry crane will be dismantled in 2 months.

Newton to BTN update

C920
Continuing from the previous post, the tunnels from Newton to Stevens are currently still being driven by the EPB TBMs. TBM1 (lower BP tunnel) is approximately 7 rings away from breakthrough when I last checked on Tuesday. The machine has spent its last 6 months repeatedly changing the cutterhead every 2-3 days, working out to cost around $2.0m each month - due to the harsh granite along the last 400m sector along the tunnel alignment which the machine wasn't designed to handle.

Nonetheless, breakthrough for TBM1 is anticipated to happen in 2 weeks time. The TBM will be dismantled in-situ and all equipments will be brought back to the launch shaft at Newton. The upper tunnel bored by TBM4 is unaffected by the granite below and is now positioned at Ring 959 before Whitley Flyover, waiting for the lower tunnel to complete before closing in.

Alstom will not be able to proceed with track laying further from Newton until STEC completes the First Stage Concreting (FSC) in the bored tunnels.


C919
Stevens station is still in the midst of concreting right now. Botanic Gardens is finishing up the roof slab and backfilling should commence by the end of the year, together with A&A works to the existing CCL.

Completed tunnel (BP bound) between Stevens and Botanic Gardens station

October summary

Okay, so trying something new that hopefully will help.
This monthly update will display the tunnel sheet for the month to summarise what has been going on in terms of tunnel completion.
Additionally, this will function as a summary of any verbal progress. In addition, probably will do up posts so that people can follow when there's an update and the respective contract pages will be updated too.

Downtown Line 2 summary for the month of October 2013

C916 - Beauty World station is back-filling the launch shaft area and left with 2 layers of struts. Strut level S2 is dismantled and just waiting to be hauled out. An Alstom sign was seen on the site and the area has been vacated to be transformed into the Temporary Staging Area for track works. Expect the road diversion at the junction of Upper Bukit Timah Rd and Jalan Jurong Kechil to be reinstated soon in view of the upcoming track works once back-filling is done.

C917 (King Albert Park) - Works have been progressing smoothly since the site take over by Mac Dow. You can now see Mac Dow banners up on the hoarding and the TBMs have been busy churning and making progress.

C917 (Sixth Avenue) - The crawler cranes on site have been raised once again since the site take over. Mac Dow banners now grace the hoarding here as well.

C918 - Works have resumed full swing. C&C area is busy. Near the launch shaft towards SAV, the concrete form works have been seen waiting to be lowered down into the tunnel area for concrete pouring.

C919 (Botanic Gardens) - The roof slab is mostly done, save for the area near to the transfer linkway to the Circle Line station. Removal of struts should begin soon and back-filling begin. Expect station modification works to come up in the Circle Line area shortly.

C921 (Little India) - Hacking of the temporary Earth Retaining System (diaphragm walls) is on going near the new exit at Little India along Race Course Road. Rebar for the vent shaft or new exit near LTA HQ is also underway with concrete pouring due to take place soon. Back-filling over the station roof slab is also underway. A new lift is being constructed at Entrance C to the station. Tracks are assembled along with sleepers at the TSA area under Alstom.

C921 (Rochor) - Breakthrough of the TBM at the Queen Street shaft in September will see the TBM being lifted out for the second drive on the Expo bound soon.