Faulty piles to further delay HK-Zhuhai-Macau Bridge

Seven of the underground piles for the Hong Kong-Zhuhai-Macau Bridge will have to be reconstructed, causing further delays to the ongoing project, Apple Daily reported on Monday, citing sources with knowledge of the matter.

A local contractor, which has already manufactured over 1,000 of the bridge piles, will have to bear the cost of reconstructing seven of them, the newspaper said.

Each underground pile is estimated to cost over HK$2 million, the sources said.

The Highways Department has confirmed that some of the piles had to be reconstructed, but did not say why. It also did not identify the contractors involved, and which parts of the bridge are affected.

Authorities said the large-scale project requires a huge number of massive underground piles, and consultants have been hired to monitor the project to make sure contractual requirements are fulfilled.

Sources said one of the seven problematic piles was located at an artificial island on the Hong Kong side.

The pile, about 3 meters in diameter and up to 70 meters in length, was installed by a contractor hired by China Harbour Engineering Co. Ltd., the report said.

Greg Wong, former chairman of the Hong Kong Institute of Engineers, explained that the piles are intended to support the weight of the bridge and are usually planted up to several dozens of meters into the ground.

The slurry inside a pile is then extracted before a steel cage is put inside and cement is poured to fill the pile, he said.

Wong said it is probable that slurry was not completely removed from the seven problematic piles or air spaces were detected in the cement fillings.

Both scenarios would cause problems to the strength and structure of the piles, he said.

However, he noted that having seven faulty piles out of the more than 1,000 needed for the project is not too bad since that would mean a replacement ratio of less than 1 percent.

Other sources said the contractors and workers often work 24-hour shifts at the project site in order to make up for lost ground from the series of delays over the past few years.

Still, the same sources express doubt on whether the project can be completed in 2017 as scheduled, noting that hundreds of piles have yet to be built along with the bridge piers and surface.

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