Tan Kah Kee Station

The overhead linkway and second entrance of the Tan Kah Kee station has recently completed all M&E installations and the final ceiling cladding have been applied to complete the aesthetics of the structure. The hoardings around the site came down last month and footpath & landscaping reinstatement works are underway. The bridge project under the 918A team has been completed 3 months ahead of the initial schedule, and should be open for public use by the end of the month.

Completion of Entrance B

Tan Kah Kee Station

Tan Kah Kee Clads (II)

Majority of the architectural works have already completed at the concourse and platform of the Tan Kah Kee station (photos were taken a month back). Cladding to the exterior superstructures like the entrance and overhead linkway is progressing, while structural steel segments for the roof of the permanent bus and drop-off bay have been installed on the site.

Photos on the surface will be updated next week. Interior pictures are provided by Ceramic Steel Alliance.

Platform of TKK station (July 2)

Tan Kah Kee Clads

Architectural works have commenced on the overhead linkway and Entrance B. The roof of the linkway have been partially completed, while vertical honeycomb-like frames - signature to the station's design, have been installed along the sides of the bridge. Entrance B is also being fitted with the panels on the exterior, and cladding is being done on the interior roof as well.

Reinstatement works around the entrance and south vent building

Tan Kah Kee - Structural Completetion

Casting of the escalator frame at the TKK POB linkway completed over the weekend. This is one of the final major structural components to be completed at the site. Fitting works have commenced on Entrance B, while steel frames for the roof have been installed on the bridge. The final set of escalators for the DTL2 will be delivered and fitted into the linkway between the bridge and the main entrance this month.

Structural completion of the transfer linkway connecting the POB and the main entrance

Tan Kah Kee - Beam Launching

The final concrete beam segments for the new POB at the Tan Kah Kee station were launched up over Bukit Timah Road in the wee hours of this morning. This concludes all beam launching works at the TKK station. Columns for the transition structure between the station entrance and the bridge are being cast at the moment.

Launched diagonal beam segments over Bt Timah Road

Render of the completed POB (Cr: Ong & Ong)

Watten Estate - Beam Launching

Beam launching works for the POB at Tan Kah Kee were carried out last week. The concrete beams for the segments across the canal and Dunearn Road have been launched. On the bukit timah side, the final 2 intermediate columns for the bridge had just been cast. The road is preparing to be permanently realigned with workers preparing the formwork for the box culvert. The final beam segment across Bukit Timah Road will be launched in about June.

April 1 - Cast of the final 2 columns along Bukit Timah Road. Reinstatement works are underway

April 1 - Beam segments launched over Dunearn Road

Tan Kah Kee Superstructures

Reinstatement works are coming up along the boundaries of Hwa Chong Institution at the Tan Kah Kee site. The site office has been demolished, while hoardings are progressively being taken down and site clearing has commenced. Our friends under the project teams from C917A and C918A are currently under immense pressure to make up for loss time as we enter the final 12 months before the Downtown Line 2 opens. We review the progress of the numerous superstructures that have emerged on the site. 

*Our updates for Botanic Gardens, Stevens, Newton, Little India and Rochor will be posted at a later date.


1. Main Entrance/ Bridge Integration
The main entrance has successfully achieved basic structural completion. The entrance, which is constructed entirely of reinforced concrete, will be integrated with the pedestrian overhead bridge through a secondary structure which is in the process of being constructed.

February 25 - Main Entrance and Station Vent Building

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

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

Cut and Cover Reinstates

The TKK cut and cover site is currently staging a final reinstatement of the track field at Hwa Chong Institution (HCI). The field is being temporarily hoarded up over the school holidays while the project team facilitate the realignment of the track. Landscaping works are also being carried out on the slope. 

Back at the station, the substructure of the entrance is almost completed as the staircase begins to form. We should see the entrance beginning to surface after CNY. At Watten Estate, entrance B has been structurally completed. Not shown in this update, piling works have just commenced for the bridge's column along the canal bank, while the escalators have been fitted into entrance B (Dec 22).

Fatality Accident

In a tragic and unfortunate mishap that went unreported last month , a worker was electrocuted by a power cable on the night of November 13 when he was hacking hardened concrete at the platform. He was not aware that the hardened concrete had covered a cable powering a temporary pump. The said concrete had dropped from the casting of the concourse opening 3 weeks before and he was assigned to clear the area after the removal of the falsework. He was pronounced dead by SCDF personnel at 11.30pm. We offer our sincere condolences to the Chinese worker involved in the fatality. 

Reinstatement of track at HCI over the cut and cover tunnel

Formwork for the entrance's staircase is underway, seen beside the JP Nelson crane

Entrance B (December 6)

Entrance B (December 15)

Watten Estate

The future entrance B of Tan Kah Kee station has begun to take shape along Dunearn Road. Spending the last 2 months on foundation works, piling and formwork for the staircase and lift shaft is completed. The project team progresses to work on the roof now as well as utility diversions and preliminary works on the foundation for the POB's intermediate column along the canal bank.

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.

Tan Kah Kee

The roof slab of the station has been completed at Tan Kah Kee and the excavation pits have been covered. The entrance can be seen in the pictures and the superstructure will be coming up from the 4th quarter onwards.

Backfilled C&C tunnels

Drawn by Seloloving, Skyscrapercity

Photo of TKK in Q4 2012. The excavation pits can be seen by the STP

Existing photo of the site which has been backfilled

Bukit Panjang bound tunnel from TKK C&C to Sixth Avenue

S605 Breakthroughs, Expo Bound Completes

The last frontier of the 16.6km long Expo Bound tunnel for the entire Downtown Line 2 has just been successfully broken through at Botanic Gardens station at 9am this morning. S605 has come a long and arduous journey from the moment of launch, facing many challenges posed by the alternating layers of mix ground and aggregates, as well as tunnelling below existing bridge, canal and tunnel infrastructures without compromising their structural integrity.

The finale breakthrough of S602 would take place at Sixth Avenue station later this month.

Breakthrough of S605 at Botanic Gardens (Photo credits - Alix Thierart)

DTL2 Tunnel Chart, Early June

Frequent updates throughout 605's tunnelling phase made possible by Masud & Bidhan, (Dongah-ACL group)

Contract 917A & 918A

Macdow has closed Fourth Avenue earlier this month to facilitate the movement of construction machinery between the previously-segregated sites. We thank one of our readers, Marcus Tan for writing in to us to inform us of the closure. This is an example of how informative contributions of site & tunneling updates can be, and are warmly welcomed. We encourage more to contact us via the feedback portal on the right sidebar.

Currently, the lane has been planned to remain closed until the completion of works in January 2016, however the project team has assured me that they will try to expedite works and push for an earlier reinstatement, possibly by the end of next year.

Signage showing the closure of Fourth Avenue

Day 8, Tan Kah Kee

Tan Kah Kee is the third and final station that was previously under Alpine. The completion contract has been renumbered to C918A and was awarded to SK E&C. Back at C915, SK had a rich experience in dealing with granite, both in station construction and in bored tunnelling, a great influence in the awarding of this contract to them as they would not only be able to operate and handle the Slurry TBMs and STPs with familiarity, but also immediately transfer their tunnelling manpower between both sites as 915 had then just completed their TBM works. Time was crucial in order to minimize further disruption to the project schedule.

TKK is working on its roof slab at the moment. The CCT has already completed its roof slab and backfilling is on going. The backfilled layer will be leveled with Hwa Chong's field and the land will subsequently be handed over back to the school.

Tunnelling Progress

S605 has advanced through the 600th ring and is currently beneath the POB at botanic gardens. Breakthrough should come within the next 2 weeks.

Cut and Cover Tunnels (North Section)

445m Cripple Siding Tunnel

Deep excavation and backfilling comparison:

April Tunnel Progress

View of launch shaft at Ubi under C929A 

DTL3 Tunnel Chart

C918A TKK-BTN Tunnel: S604 BP (Green), S605 EP (Orange)

Completed BP tunnel bored by S604

Dismantling of slurry pipes and backup gantries rail at Ring 585 (and progressing back to TKK)

S605 currently beneath the canal wall at the white patch

The remaining TBM under SK, S605 has crossed the ORRS and DTSS and is starting to curve back towards Botanic Gardens. They are replacing the cutters every few days due to the harsh granite conditions posed in this region. We might see breakthrough only in June. The cross passage is currently being mined beneath the underpass and canal. Ground improvement works were carried out 2 weeks ago with the temporary closure of one road lane.

C917A KAP-SAV Tunnel

S602 has caught up with progress. It will follow a very similar timeline with its sister TBM. A month would be spent tunnelling through the granite between R680-R730. Final breakthrough expected in July.

S603 is doing about 4-6 rings per day now. All going well we'll see a breakthrough next month.

TBM Josephine sees light of day

After the arduous task of boring the Bukit Panjang tunnel from Tan Kah Kee station to Botanic Gardens, the TBM named Josephine is finally dismantled and brought to the surface. A few photos commemorate the milestone in achieving another tunnel completed under Downtown Line 2 (DTL2).

March Tunnel Progress

C937 - Breakthrough of TBM 2 at Chinatown on Mar 24

C917A

Closure of centre carriageway to conduct SI

C917A
S602 has resumed tunnelling though the battle against ground is not in their favour. Downstream along Maple Ave MacDow is conducting SI along lane 3 in anticipation of granite currently challenged by its sister TBM.

S603 at 710 rings (Mar 20, ~72% completed)
TBM has slowed down to 1 ring per day. It is crossing the 2nd diversion canal at the moment, concluding the end of the section weakened by granite. Cutterhead is being replaced every 3-4 days. This is alike the challenge faced by STEC's TBM1 near Stevens station last year. The tunnel route is expected to be trouble-free from here till breakthrough point at SAV, exception of another possible section of granite lying below the junction of Sixth Avenue.

C918A

S605 crossing the canal beneath the Farrer Flyover

C918A
S605 at 446 rings (Mar 19, ~66% completed)
TBM has paced down. Breakthrough together with S603 should only take place in May.

Remaining gantry crane standing on site

 STEC has decommission 2 of its gantry cranes at Newton the past week. The remaining one along the BP tunnel should be taken down by the end of March. Backfilling of the shafts are starting.

With thanks to Stefano for his contribution.