SG50 HUAT! you may drown by sea water leaking into MCE Tunnel video

mortarmafia said:

I received via WhatsApp yesterday.

https://youtu.be/VAs8ulrWkoI

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40% saving on piles

Underlying the stiff layer of ground improvement are bored reinforced concrete piles. On most previous cut and cover projects in Singapore, engineering solutions have considered the performance of piles in compression only. But the piles work in tension too. Analysis showed that uplift exerted by earth pressure on the DCM layer would cause it to heave and bend. But we found that this was reduced by the action of the piles in tension. This is something that’s usually ignored – but by making the piles stiffer, we were able to anchor down the DCM layer.

Stiffening the piles required additional reinforcement. To avoid unnecessary use of steel and resulting cost, we analysed the forces acting on every one of the 2500 piles across all three contracts. Normally, reinforcement would be designed to cope with the maximum load and applied to each and every pile. Instead we assumed a minimum and worked up from there. This delivered a 40% saving on steel reinforcement across the project.

The DCM layer restrains movement of the retaining walls. Its performance in combination with the piles meant that its thickness could have been reduced to 8m while providing the stiffness required. However, for comfort 10m of DCM treatment was carried out. This was still significantly less expensive than jet grouting and benefited pile design. The bond between each pile and the DCM layer relies on the contact area between them. Increasing the slab thickness from 8m to 10m enabled a 20% reduction in pile diameter, delivering a 36% saving on concrete.

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US$70m saving on struts

In another departure from convention, the contractors proposed constructing retaining walls using 1.2m to 1.5m diameter pipe piles instead of the common sheet and soldier pile combination. Pipe piles are far stiffer, making it easier to comply with the LTA’s very tight wall deflection criteria. This meant that two levels of struts were more than adequate, rather than the four to five strut levels specified in the indicative design.

With the first strut level just below ground level, the second was installed at mid-height, 7m down, with deep level restraint provided by the massively strong DCM ground improvement layer. On each contract, the elimination of every strut layer has saved almost US$24 million, yielding a US$70 million combined benefit. Reducing the number of struts from five to two layers has offered a huge time saving and dramatically improved worker safety, with lifting and manual handling operations cut by 60%.

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xpo2015 said:

The spray profiles looks like water sprinklers getting turn on accidentally!

Who is spreading rumours and lies again? Must leeport to Police and have him arrested!!

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laksaboy said:

Innovative free state-of-the-art car wash as part of SG50 celebrations.

Sinkies really complain too much. Count your blessings and be grateful. Don't be seditious.

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Reddog said:

If you are in the MCE and the roof collapse, you better be prepared for you own state funeral. No escape possible.

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bushtucker said:

it is not sea water leaking into the tunnel. someone accidentally turned on the fire sprinklers.

sinkies, being kiasu and kiasi, immediately jumped to conclusions and proclaimed sea water leakage.

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laksaboy said:

Don't be too sure about that. When that engineer died in the Nicoll Highway collapse, all he got was a lousy bench for his 'sacrifice'.

Only people such as Kwa Geok Choo get a state funeral, for her immense contributions to the nation.

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