An engineer checks the beam supporting pad at an area on the elevated section of HCMC's first metro line, January 2021. Photo by VnExpress/Pham Quynh. |
Speaking on condition of anonymity, the source said the agreement between the city Management Authority for Urban Railways (MAUR) and the contractors, Civil Engineering Construction Corporation No. 6 (Cienco 6) and Japan's Sumitomo Corporation, requires them to use a certain quality of elastomeric laminated bearings pads, which are reinforced steel plates sandwiched between layers of rubber.
The pads are designed for use in bridge and building construction as a beam support.
But the contractors have used at least two pads of inferior quality, and MAUR has already warned them this could threaten the quality, safety and life span of the project, the source said.
In October one of the pads fell out from between two beams on 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.
In December MAUR inspected all the pads itself and found two of them were lighter than the required standard, and suggested that could have caused the cracks seen in October.
It said EB1 and EB4 on the elevated section weighed only 117 kilograms, or nine kilograms less than the agreed weight.
One of the Elastomeric Laminated Bearings pad that has been removed from the project to serve the investigation. Photo by VnExpress/Pham Quynh. |
This month a team of independent inspectors found another pad had moved from its position on the elevated section and does not fit properly.
They were imported from South Korea but made in Malaysia, and around half the pads used in the metro have been sourced from there. The rest were made in Japan.
The contractor has not made any statement yet about the issues.
Officials from the Ministry of Construction have visited the site to check.
The metro route No.1 will have 14 stations, three of them underground, and cost an estimated VND43.7 trillion ($1.89 billion).
Work on the much-delayed project is more than 80 percent complete.
The city hopes to begin commercial operation by the end of this year and build a total of eight metro lines running a total of 220 km.