Piling at Mayflower (II)

Bore piling works continue at the Mayflower site. A second traffic diversion was implemented mid-December at the junction of Street 11, swinging the twin carriageway of Avenue 4 towards the west. The diversion will last for 2-3 months. Instrumentation works have also begun with tiltmeters installed along the columns of the HDB flats surrounding the site.

Penta Ocean from the neighboring contract T211 is also preparing a small site south of Mayflower for preparatory works of the 2 TBMs that will be driven from Bright Hill, both of which will go beneath the foundations of Block 258. More will be shared in the T211 update.

December 24 - Panorama of Mayflower, T210

December 24 - Close up of traffic diversion 1A

Lentor D-walls & Piles

D-walling works at Lentor has commenced this quarter. Close to Yio Chu Kang road, the team is in the midst of constructing the sheet pile for the subway that will link to the station entrance at Calrose. Sheet piles are a favorable method of constructing an ERSS due to the time efficiency in installation and transportation. The interlocking steel segments are also earth tight and water resistant. This method is hence commonly used in shallow linkways and cofferdams.

We expect the completed section of sheet pile to be subsequently decked over by a second and more permanent traffic diversion at the junction of YCK/Ave 4/Lentor Drive next year. This is for the construction of the remaining section of subway beneath the existing diverted road, and subsequently the construction of the entrance at Calrose itself. This diversion would then probably last until the completion of the project.

Sheet piling for the subway leading to the station entrance at Calrose

Panorama of 5XO

At the 5XO site, Avenue 4 was diverted at the end of Q3 and with the site cleared, hoardings are going up along the west side where sheet piling works have commenced. D-walling works should commence from next month as well. To the east, silos and a desander plant have been assembled to support the impending D-wall construction.

Project notice for 5XO (transcript):

- Identified trees along AMK Avenue 4 have been fully removed to facilitate crossover tunnel box construction (5XO)
- Road diversion works at 5XO will be carried out in 2 stages. Traffic Diversion 1 completed on 29 September 2014.
- Traffic diversion 2 at the junction of Avenue 4/5 are planned to commence in early January 2015.
- Tubular pile, steel deck and RC drain has been constructed close to Block 643
- Sheet pile works at Blk 613,614,615 has commenced from mid Dec and will last for a duration of 3 months.
- Installation of monitoring instruments along the ground and buildings
- D-wall works along Blk 613/4/5 planned to commence from end November (delayed)

Tagore Piles & Excavates

Tagore is currently leading in progress due to the large number of equipment brought in by Leighton-John Holland. The ERSS along the south side of the station and launch shaft has completed and excavation works have begun, with the first layer of struts have been installed. Ground treatment works are being done beside the launch shaft as well. Piling works continue at the north side and a desander plant is being constructed next to the Tagore site office.

NFM Technologies has been chosen as the manufacturer to supply 3 Slurry TBMs for T208. Upon completion of the first tunnel towards Lentor, 1 machine will be redriven in the direction of Springleaf. Pigott Shaft Drilling shall supply the slurry treatment plants for the 3 slurry shield machines.

9 piling rigs, 3 crawler cranes and a mobile crane mobilized at the Tagore site

Mock up of 1 one of the 3 NFM Slurry TBMs to be used for T208