The Land Transport Authority (LTA) has banned a professional engineer from working on any LTA projects after formwork failed at the construction site of the Great World MRT station in River Valley in January.
The engineer, Mr Gary Ng Wee Giap, had "under-designed a key component of a temporary work installation" at the station along the Thomson-East Coast Line, an LTA spokesman said in an e-mail reply to The Straits Times on Wednesday. The authority said it "removed the engineer" from the ongoing project last month.
Mr Ng's design had failed load safety requirements, which breached workplace safety and health regulations, according to an e-mail LTA sent to the main contractor, Tiong Seng-Dongah Joint Venture, seen by The Straits Times.
As a result, the formwork failed during skin wall casting at Entrance B on the upper concourse level, the e-mail stated. The process mainly keeps water from seeping through walls.
An independent supervision team discovered the miscalculations when LTA conducted a review after the failure.
The Straits Times understands that no one was hurt when the failure occurred, and that the construction timeline of the Thomson-East Coast Line will not be affected. The new line will open in stages next year as planned.
The LTA spokesman said that the design flaws have since been rectified. "Stringent measures are in place to ensure the safety of all personnel," he added.
Mr Ng, who runs GNG Consultants, has been barred from working on all LTA projects, the spokesman said, noting that the agency takes lapses seriously.
The firm is a subcontractor to Tiong Seng-Dongah Joint Venture.
Still, other factors may have affected design accuracy, said Mr Bernard Soh, Singapore Institution of Safety Officers' current president. He said professional engineers typically process information prepared for them and miscalculations by other parties could have resulted in the error.
Mr Han Wenqi, a safety officer of 12 years, said that even after temporary structures for construction are put in place, regular checks for issues such as stress fractures need to be conducted regularly.
Correction note: In an earlier version, we stated that the formwork had collapsed at the Great World station late last year. It should be that formwork had failed at the Great World station in January. We are sorry for the error.