Another fault seen in HCMC metro line

Three months after a supporting pad for beams fell off, another one on HCMC’s metro line No.1 has deviated from its position.

When checking the metro line to figure out why one of the Elastomeric Laminated Bearings pads had fallen out from its position between two beams on the line’s elevated section last October, a team of independent inspectors has found another pad has moved from its position.

These pads are made from high purity elastomers that encapsulate layered internal steel reinforcing plates and are designed for use in bridge and building constructions for beam support.

The faulty pad has both sides not matching the position it was placed in, according to the metro line’s investor, HCMC Management Authority for Urban Railways.

The faulty pad is also on the elevated section of the line, which runs 19.7 km (12.24 miles) from Ben Thanh Market in District 1 to Suoi Tien theme park in District 9.

The incident in October was detected after cracks were seen on the section in Thu Duc District. Soon after, the contractor, a consortium comprising Vietnam’s Civil Engineering Construction Corporation No. 6 (Cienco 6) and Japan’s Sumitomo Corporation, said they had fixed the issue. Project manager Shigeki Ihara had said then that the incident was just a « single case » involving one beam.

However, the contractor made no mentions of how the pad had fallen and how it would affect the life and safety of the project.

Explaining the delay, the contractor said that the Covid-19 pandemic has not allowed it to bring Japanese experts into Vietnam for an inspection.

The project’s investor, MAUR, decided to jump in to have the entire project inspected.

Last month, it found that pads lighter than designed have been used for supporting beams in the metro line. It said the EB1 and EB4 pads on the metro line’s elevated section weigh 117 kilos, which is nine kilos lighter than the design approved five years ago.

The contractor has so far not been able to provide any explanation for the October incident.

Following such developments, HCMC has tasked an inspection team to check the entire project.

Regarding the new fault found in the pad, Ha Ngoc Truong, deputy head of the city’s Bridge, Road and Port Association and a member of the inspection team, said experts are looking at the issue « very carefully. »

« For now, the reason has not been identified and therefore it is impossible to make any in-depth professional assessment, » he told the Dan Tri newspaper.

Both the pads were imported from South Korea, and around half of the pads used in the metro line No.1 are sourced there.

The metro route No.1 will have 14 stations – 11 on elevated sections and three underground.

Its construction is expected to cost VND43.7 trillion ($1.89 billion).

Work on the much-delayed project, which began in August 2012, is more than 80 percent complete now.

The city hopes to complete 85 percent this year and begin commercial operations by the end of next year.

HCMC plans to build eight metro lines running a total of 220 km.

By Gia Minh – VnExpress.net – January 16, 2021