November Tunnel Progress

November 13

TBM2 docked into the Upper Cross Street retrieval shaft earlier today. The completion of this Expo bound tunnel structurally links the network of DTL tunnels from Gali Batu to Bedok Reservoir on both bounds.

November 23

The BP Bound TBM has just launched at the Stadium Shaft towards Tampines Central. This is also the final TBM launch out of the Stadium Shaft. Breakthrough is estimated around Chinese New Year 2015.

For the month of December, we can look forward to the
- Breakthrough of Expo Bound TBM between Stadium Shaft and TPC (926)
- Breakthrough of BP Bound TBM between Prison Shaft and BDR (926)
- Breakthrough of Expo Bound TBM between UPC and XPO (923)

DTL3 tunnel progress as of Nov 23

C929A UBI Launch Shaft

Nov 13 - Breakthrough of C937 TBM2 at Upper Cross Street

C929A Bracing for CP Excavation

Fort Canning flashback

A few years back, before the area along the Singapore River and River Valley Road got torn up, quite a different landscape existed than that which can be found at the Fort Canning station site today. Take a look at the differences in landscape since.

11 October 2011

11 October 2011

Chinatown breakthrough

As mentioned in our earlier post, C937 finally broke through to the reception shaft at Upper Cross Street cut & cover site. The process has been a long and arduous one as the ground showed increasing settlement as the machine neared the end point. Care had to be taken to mine the last few metres or so to prevent excessive settlement causing the buildings on both sides to move and potentially see unwanted movement of the road above.

Nevertheless, after several weeks, the team safely accomplished breakthrough, linking the stage 1 tunnels to the stage 3 tunnels. Here are a few photos of the occassion.

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.

C937 breakthrough coming

Contract 937 is for the construction of Fort Canning station and tunnels to Chinatown and Bencoolen stations. Contractor GS E&C is eagerly awaiting the breakthrough of their machine boring the Bukit Panjang-bound tunnel towards Chinatown tomorrow. The reception shaft located next to the subordinate courts will receive the machine that bored underneath the Singapore River riverbed and forms the lower of the two tunnels that will eventually connect the stage 3 station to Chinatown interchange. In order to pass through a tight corridor, constrained by the Central mall and Central Expressway (CTE), the tunnels have to stack - running one on top of the other. The typical construction sequence is to bore the lower tunnel to reduce the amount of movement encountered subsequently. This lessens the amount of stress that the completed tunnel is subjected to. We look forward to bringing you more details once the breakthrough is accomplished tomorrow.

February Tunnel Progress (1)

C917A (Yellow sector completed by Alpine)

C917A
S602 still undergoing grouting outside the Cascadia, at over 200 rings. This will certainly be the last BP bound tunnel to complete within Stage 2, with an expected breakthrough only after June.
S603 at 605 rings (Feb 5, ~61% completed) TBM is quickly inching towards SAV. Expected breakthrough April.

C918A

C918A
S604 at 501 rings (Feb 3, ~76% completed) Expected breakthrough end March
S605 at 344 rings (Feb 2, ~51% completed) Ether BTN or SAV would see the final EP bound breakthrough as both machines seem likely to complete tunelling within a similar time span with under 400 rings more to cast. Expected breakthrough April

C921
S608 is about 2 rings away from breakthrough and is scheduled to complete its Expo bound drive by this week. Detailed update to come.

C937
TBM2 is now at 295 Rings. As mentioned in the previous post, the main body of the machine is currently underpassing the CTE portal at Upp Cross St. Advancing around 3 rings each day its most likely to reach its reception at Chinatown early March.

TBM undercrossing the CTE portals

Fort Canning update January

Contract 937 is for the construction of Fort Canning station along with two sets of main line tunnels - one towards Bencoolen station and another towards Chinatown station. The tunnels towards Chinatown station are being dug by a single TBM, known as TBM2, which will make two runs from the West Launch Shaft to the reception shaft at the end of Upper Cross Street, near the Chinatown station. Due to a tight fit amongst the tall buildings, the tunnels will have to stack one over the other in order to gain access to the reception shaft with the Bukit Panjang bound taking the lower level. An escape shaft will be built at Havelock Road to provide for emergency egress from both tunnels. 

Currently, TBM2 is undergoing a final cutterhead intervention where the blades at the front of the TBM are replaced and general servicing of the cutting equipment is performed. This is done under compressed air to stabilise the soil so that it does not collapse into the area where the workers are working from.

28 January 2014
Photo credit - Mohd Iskandar Jack

Fort Canning update

Fort Canning station is progressing well with a traffic diversion of River Valley Road expected soon. This is to facilitate diaphragm wall works and subsequent excavation to build the station roof. Once this is completed, the road should be able to be realigned over the completed works area.

TBM2 towards Chinatown has crossed the original Singapore River as well as its temporary diversion. As of last week, the TBM was at ring 136 which is under Merchant Road, next to Riverside Point. This is roughly halfway of the drive to the Chinatown reception shaft at the cut & cover portion along Upper Cross Street. Due to the tight fit, the tunnels here will stack one on top of the other with the Expo bound being the upper tunnel and Bukit Panjang bound the lower tunnel. An intervention shaft is located along Havelock Road for emergency egress during fire occurrences.

23 October 2013: Inside the station box area
Credit to Boy Is

23 October 2013
Credit to Boy Is

23 October 2013
Credit to Boy Is

23 October 2013
Credit to Boy Is

23 October 2013
Credit to Boy Is

23 October 2013
Credit to Boy Is

06 November 2013
Credit to Mohd Iskandar Jack

DTL3 October update

In this post, we bring you up to date on the goings on of construction on Downtown Line stage 3 for the month of October.

Firstly, a listing of the TBM shields that we have.

C923 - S-761
C923A - TBM1 (Argo) & TBM2 (Hermes)
C925 - TBM1
C926 - TBM1 (Chloe), TBM2 (Beatrix), TBM3 (Hayley) & TBM4 (Lizzi)
C927 - TBM1 (Tierra) & TBM2 (Kaida)
C928 - TBM1
C929A - S-685 (Harmonica), S-686, S-693 (Jupiter) & TBM4
C930 - TBM1 (Gaia) & TBM2
C931 - S-737 (Jet)
C932 - TBM1 (Xena) & TBM2 (Gabrielle)
C933 - S-739 (Whampoa), S-740 (Bendemeer), S-741 & S-742
C935 - S-759 & TBM2
C937 - TBM1, TBM2 & TBM3

Green - completed
Orange - tunneling in progress
Aqua - launching soon

So here's an update on some of the TBM tunneling progress. We don't have all the progress available unfortunately. More details and an easy display will be coming up down the line in November and beyond.

C923A PIE shaft to TPE
TBM1 - Completed
TBM2 -
Total: 1074 rings

C926 Stadium shaft to TPW
TBM1 50+ rings at end August
Total:

C927 BDN to BDR
TBM1 678 rings. TBM2 75 rings.
Total:

C937 FCN to BCL
TBM1 at 105 rings
TBM3 - - - - -
Total:

FCN to CNT
TBM 2 at 54 rings
Total:

 In addition, excavation seems to be progressing pretty well overall.

C922 - Expo station has already reached the base slab level at portions of the station.

C925 - Tampines East station is in the process of constructing the retaining walls. The TBM was lowered within the last month and assembled at the launch shaft ready for the Expo-bound drive to Tampines Central station.

C926 - Tampines West is still in the process of constructing the retaining walls as the Tampines Avenue 4 was only shifted over the completed portion a few months ago.

C928 - Bedok North has excavated most of the soil from the station pit area. They will be progressing onto the structural works soon.

C929 - Kaki Bukit station has the top layer casted and excavation work is progressing below using the top-down method where the permanent structure is cast before moving lower to commence excavation at the preceding level below.

C933 - Bendemeer station has seen some under-platform level work go on. Concrete pouring has also been taking place.

 C935 - Jalan Besar station is also employing the top-down method of construction. Most areas have progressed to level 2 of excavation.

C937 - Fort Canning station is progressing swiftly with the top-down method as well. Excavation continues on.

Do check back for more updates as we begin filling up the individual station pages with photos. Feel free to drop us a line if you have anything to contribute too, via the comments section. Have a great day all!