Wednesday, August 06, 2008

MRR2... strike three...

This is the 3rd time that the Middle Ring Road 2 (MRR2) is being closed for the shoddy work done by the contractors. Why is the government so dumb? Lucky for Samy Vellu that he is out of the ministry but still he must be answerable as the two repairs were done during his time. And he must answer to this also (taken from Sun2Surf)...
MRR2: Govt went against our advice, says Halcrow
by Tan Yi Liang

PETALING JAYA (Aug 5, 2008) : The solution adopted by the Works Ministry to repair the original cracks that appeared on the Middle Ring Road II (MRR2) flyover in Kepong on Aug 9, 2004 were "not recommended" by Halcrow Consulting Ltd.

"I would like to emphasise that although Halcrow conducted detailed investigations into the original cause of the cracks, the government went against our advice not to use pre-stressed carbon fibre to strengthen the pillar heads because of its limited ductility (capacity to deform before fracture)," Halcrow engineer Roger Buckby said.

He said Halcrow had identified the primary cause of the cracks as "expansion caused delayed ettringite formation (DEF) due to the formation of sulfate and an alum-based mineral compound called ettringite".

"Ettringite is a normal product of cement hydration. When you have fairly high temperatures (above 70 degrees C), the formation of ettringite is delayed and incomplete, but if water can penetrate in a later stage through cracks and seepage in the hardened concrete, which it did on the MRR2, it will expand and cause cracks," said Buckby, who prepared a report for Halcrow which was submitted to the Works Ministry in 2004.

Buckby, who spoke to theSun in a phone interview and later via email today, stressed that Halcrow was not the company responsible for carrying out the final repair works on the MRR2 pillars which cracked on Sunday, raining concrete fragments on motorists from under the flyover.

"My company was not appointed to undertake the detailed design and supervision of the remedial works, which I understand was done by Leonhardt & Andra, a German consultant," he said, pointing out that the recent incident was possibly due to a rupture of one of the prestressed carbon fibre straps.

However, Buckby added: "Without close inspection, I cannot give an informed professional opinion on the cause, or on the nature and extent of any remedial works that may be required, but it is clearly of concern."

It was the third time since the opening of the flyover, in stages between 1999 and 2003, that cracks have forced the closure of the 1.7km express link.

It was first closed in August 2004 when cracks were found on 31 of its 33 pillars as a result of improper anchoring of the crossbeams. It was repaired and re-opened on Nov 13 the same year.

The MRR2 was closed for the second time in February 2006 and re-opened fully to traffic the following December after repairs were completed.
You pay these guys millions yet you didn't take their advice. Now we have to repair the damn thing again... for the third time!!! This is tax payers money we are talking. And we are talking millions down the drain. Can't wait for government response to this... don't know what bullshit answer they are going to cook up. Next time put a design guarantee clause in the contract. Make it 10 years long. If the design is flawed.. then Government will be covered and the contractors are answerable for their shoddy work. Haiya.. itu pun kena ajar ke..?

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