Upper Thomson Cast (III)

Excavation works by TBM 3 concluded earlier this week, completing the 960-ring Woodlands Bound tunnel between the Upper Thomson Launch Shaft and Caldecott Station. TBM 2 will similarly arrive in a month's time, thereafter concluding tunnelling works for the first 2 stages of the line.

Casting of the station, entrances and ventilation structures are progressing, with basic structure of the station targeted to be achieved after the next quarter.

Completion of the 1.35km Woodlands bound tunnel bored by TBM 3 between ULS and Caldecott Station

Breakthrough of the Japanese TBM at Caldecott Station on March 12, 2018, concluding 16 months of tunnelling works

Upper Thomson Cast (II)

Excavation of the station has reached the formation level and casting of the underplatform/platform level are in progress. Excavation and RC works are simultaneously taking place across the entrances. TBM 1 has completed the second drive to Upper Thomson Station last month and dismantling works are in progress.

Completed concourse slab towards entrance D. Internal RC wall works for south TVF/VS/VE in progress.

Upper Thomson Cast

Structure of the station is at varying progress with the basement roof and concourse slab cast at different zones. With the bored piling and ground improvement works completed, a total of 3 telescopic clamshell excavators are now facilitatating the excavation works for the top-down construction of the station. 

Upper Thomson Station

Upper Thomson Excavation

D-walling works for the station was completed earlier this quarter and the associated silos have been dismantled. Bored piling works for the station's foundation are taking place at the south side of the station, while excavation works on the north end has reached the concourse level.

Bored piling works around entrance D

Piling at Upper Thomson (II)

Diaphragm wall structure for the station is finishing up and construction of the roof slab is being done. TBM 1 has completed its first drive to Upper Thomson station and relaunch for the second drive is being prepped.

D-wall, bored pile, JGP, WSM and excavation works for roof slab construction taking place concurrently at Upper Thomson

Upper Thomson D-walls (IV)

The last phase of the d-wall works, together with piling works for Entrance D, have finally commenced with the full implementation of the 3rd traffic diversion scheme. Excavation works should commence by the middle of 2017.

D-wall grab mobilized back on site for the panel excavation

Upper Thomson - Canal Diversion

The canal running parallel to the station has been diverted and demolishment of the canal is taking place along the diverted stretch of the northbound carriageway. The 3rd traffic diversion will be fully implemented upon the completion of bored pile works at the center of the station box, following which the demolishment and backfilling of the remaining stretch of canal, together with the crucial diaphragm wall works would take place.

A heavy-duty crane is currently being assembled at the Upper Thomson Launch Shaft, awaiting the arrival and subsequent lowering of TBM 3 next Friday. TBM 1 has completed its initial drive and is transitioning to its main drive. TBM 2 is on its initial drive to Caldecott.

Completion of canal diversion and demolishment of former canal in progress

Piling at Upper Thomson

The canal diversion works are progressing and bored pile works for the station foundation continues.

Upper Thomson Grouts

Numerous grouting are being carried out across the Upper Thomson station site where the first phase of the diaphragm wall works have completed. Piling works are taking place at the entrances. Tunnelling works are set to begin by the 2nd quarter following the assembly of the first TBM last month.

Assembled gantry crane and TBM 1 at the ULS

Upper Thomson D-walls (III)

The diaphragm wall along the north wall has completed and the 2nd stage of traffic diversion is being implemented in phases, after which the d-walling works would continue along the center of the road. The road realignments are facilitated in tandem with the phase-by-phase construction of the new canal, which will sit on the roof of the Upper Thomson station box.

Upper Thomson D-walls (II)

Trenching of the diaphragm wall as well as boring works for the king posts continues at the Upper Thomson Station. The new canal is currently being constructed. Excavation works at the Upper Thomson Launch Shaft is halfway completed and grouting is taking place at the ends of the launch shaft ahead of the projected TBM launch early next year. The slurry treatment plant is also being assembled.

Upper Thomson D-walls

D-walling works continue at the Upper Thomson site. Piling works have completed at the Upper Thomson Launch Shaft (ULS) by the end of May and shoring/excavation works have commenced. Tunnelling works are scheduled to commence at the ULS by December this year.

May 13 - UTS site (cr: Bachy Soletanche Singapore)

July 11 - Excavation at ULS

Upper Thomson Diverts

The first traffic diversion at the site of the Upper Thomson Station was implemented in February. The realignment of both carriageways to the south makes way for the initial earth retaining structural works on the north face of the station box, which should commence by next month.

At the entrance opposite Thomson Plaza, sheet piling works were carried out throughout the past month as well. The primary earth retaining structure for the entrance is now being d-walled. Silos have also been erected further up Bright Hill Drive. Piling works are now being done at the entrance of the former Thomson post office.

This post consists of the update for both the Upper Thomson Station and Upper Thomson Launch Shaft.

Update preview - Upper Thomson Launch Shaft

March 20 - Upper Thomson Station

Upper Thomson D-walls & Piles

The station's ERSS will be constructed from north to south, with an implementation of a traffic diversion for each respective phase. The first traffic diversion has been scheduled within the next 2 months. King posts are being driven down along the former canal which will support the deck for the traffic diversion to come, while D-walling works have commenced at the entrance on the former site of the Thomson Post Office by Bachy Soletanche, subcontracted by Sato Kogyo.

Hirose has been subcontracted for shoring works under T212.

Upper Thomson Launch Shaft

As a kind gesture, the project team decided to install 12m high acoustic barriers at ULS for the Shunfu residents despite the site being a reasonable distance away from the blocks. Due to the obstruction of view, our updates will now be viewed upfront from the Lakeview side.

D-walling works at Entrance C - Bachy Soletanche Singapore

Driving of king posts into the former canal

Piling at ULS

Coring and piling works have commenced at the Upper Thomson Launch Shaft (ULS) over the past month. At the site, 2 BG40s rigs and a mobile crane have progressively arrived while 4 pairs of bentonite silos have been erected. The permanent-temporary walkway pavements and site access around the launch shaft have also been fully done up by Sato Kogyo. The launch shaft is on track to be done up by the middle of next year and subsequently see its first Slurry TBM being launched out towards the end of 2015.

The photos consolidated in this update were taken on Oct 27, Nov 11 and Nov 26.

New site access to the south of ULS

Timelapse every 15 days

Upper Thomson Diverts

After 3 months of preparation works, Sato Kogyo has successfully implemented their first traffic diversion along Upper Thomson Road at Lakeview, where the future launch shaft (ULS) sits. The old pedestrian overhead bridge (POB) will be demolished at once, and piling works will begin for the launch shaft by year end once the site is cleared.

Upper Thomson Launch Shaft (ULS)

ULS will launch out 3 Slurry TBMs - 1 which will do a double drive to Upper Thomson, and another 2 towards Caldecott station. A Slurry Treatment Plant (STP) and Gantry Crane will be constructed along the former road. The team hopes to launch the first TBM by the end of 2015. Excavation of the tunnels will take some 18-24 months, and might possibly drag on into early 2018. Once the tunnels have its first stage concrete (FSC) completed, the cross passage within the shaft will been built. The shaft will be backfilled and reinstatement on the surface will only take place then.

T212 Tunnel Chart

Upper Thomson Station (UTS)

Canal diversion work is still on going at the station side. For the ERSS, Upper Thomson would be implementing the diaphragm wall construction. Trenching works should begin by year end.

ULS pre-diversion (September 12)

Upper Thomson Road on Sunday morning

Station side

ULS - Preparations to Divert

Works are in full swing for the staging of one of the biggest road diversions to be implemented along the corridor of the Thomson Line. Road surfacing has begun for the new Upper Thomson Road that will swing round the existing road which will be excavated up for the Upper Thomson Launch Shaft (ULS). The new POB has already been launched up this week.

The diversion will take place on Sunday, September 14 and would last throughout the entire duration of the tunnelling phase of the project, estimated to be completed in 2019.

August 29

Northbound road has completed surfacing

Roof of the new POB is almost completed

Upper Thomson - It's Beginning

Almost all vegetation have been cleared at the station site and ULS, with the center median hoarded up with concrete barriers while compact excavators remove the remaining obstructions beneath while canal diversion works take place.

Tunnelling to CDT is set to be a battleground between earth and infrastructure. A 500m section below Marymount Road will be bored parallel, directly below the existing Circle Line tunnels with 10-15m clearance, something that the local authorities have not endeavored before. Other challenges thrown into the works include tunnelling below the existing Macritchie Viaduct, Marymount Flyover, DTSS as well as concurrent projects like the North South Expressway and SPPG cable tunnel taking place simultaneously.

Tunnelling works at ULS are scheduled to commence by 2H 2015. ULS will have a cross passage integrated within the shaft. ULS-UTS will have a single CP, while ULS-CDT will feature 4 CPs within the tunnels.

Update Preview - Station box looking north

Update Preview - Station box looking south

Update Preview - Upper Thomson Launch Shaft (ULS)

Upper Thomson Clears

We look at Contract T212 which oversees the construction of Upper Thomson station as well as twin bored tunnels between UTS and CDT stations. About 1/3 of the marked trees to be cleared have already been chopped, while utility diversions are still underway as of today.

More information will be released upon commencement of construction. T212 will see the construction of 2 main C&C structures - Upper Thomson Station (UTS) and Upper Thomson Launch Shaft (ULS). The launch shaft will be an isolated structure built between UTS and Caldecott stations, located directly beneath the existing Upper Thomson Road, in front of Shunfu Gardens. A road diversion within the next few months would be necessary to facilitate the shaft and subsequently tunnel works. A single TBM will launch twice from ULS to UTS while 2 TBMs bore towards CDT. The site office is being constructed infront of Shunfu Estate.

Railings along the centre divider being demolished

Contract Awards - T208 & T212

The LTA has awarded two contracts for the Thomson Line (TSL) today - T208 for construction of Springleaf station and T212 for construction of Upper Thomson station. T208 is awarded to the Leighton-John Holland Joint Venture (currently doing C935 Jalan Besar station on DTL3). T212 is awarded to Sato Kogyo (currently doing C928 Bedok North, C932 Mattar and C936 Bencoolen stations on DTL3). Also issued were some renders of the stations.

Springleaf

View of the entrance at Springleaf station

Platform view at Springleaf station

Upper Thomson

View of the entrance of Upper Thomson station

Platform view at Upper Thomson

Construction begins in the first quarter of 2014 for completion in mid-2020.