Experts criticise MRT-6 probe body, call for tech overhaul

The first investigation report on the initial bearing pad incident on the elevated structure of Dhaka's Mass Rapid Transit Line 6 (MRT-6) last year failed to examine the possible displacement of nearby pads, raising questions about its thoroughness, according to experts.

The Financial Express (FE) recently received a copy of the report, which highlighted four possible causes for the incident, including repeated deflection of the girder from daily train operations, creep and shrinkage of the girder in the long-span section between piers 425 and 428, the effect of the sharp S-curve and long rail sections potentially pulled by temperature variations, and centrifugal forces -- although the last was not clearly explained.

However, the report made no reference to nearby piers, including pier 433, where a similar accident occurred on Sunday, resulting in a nearly 100 kg bearing pad falling.

The Sunday incident occurred in a critical S-curve section with a height increase, raising further safety concerns. The report did note slight shear deformation in bearing pads on piers 428 and 429, in the same direction as the previously dropped pad on pier 430.

Technical experts have explained that "creep" refers to permanent, time-dependent deformation under sustained load, while "shrinkage" refers to time-dependent volume reduction caused by moisture loss or chemical reactions. In concrete structures, creep leads to ongoing bending or shape changes under weight, whereas shrinkage causes material contraction that may lead to cracks.

Engineers and insiders, both local and international, have criticised the investigations, stating that committees formed by non-technical personnel are unlikely to identify the true causes.

They also questioned the focus and composition of the committee investigating Sunday's accident in the Farmgate area of Dhaka, citing a lack of relevant technical expertise.

The Road Transport and Highways Division (RTHD) under the Ministry of Road Transport and Bridges formed the latest investigation committee with Bridge Secretary Mohammad Rouf Ahmed as convenor.

Members include BUET Mechanical Engineering Department Professor ABM Towfique Hasan, MIST Civil Engineering Department Associate Professor M Zahidul Islam, and MRT-5 South Project Director M Abdul Wahab. Deputy Secretary Asfia Sultana serves as member secretary.

Following criticism for appointing the bridge secretary, who was managing director of Dhaka Mass Transit Company Limited (DMTCL) during the first accident, the RTHD later added the chief engineer of LGED as a member. All members operate under the supervision of the special assistant to the chief advisor on Rail and Road.

Engineers, however, noted that neither the previous nor the current committees include bridge experts, even though bearing pads are a critical component of bridge design.

Dr Hadiuzzaman of BUET's Civil Engineering Department told the FE that both accidents indicate a design flaw, but the first investigation failed to propose engineering solutions because the true causes were not identified.

"MRT is not like a traditional train system," he said. "Committees must select highly technical experts familiar with complex metro systems. Committees led by project insiders, consultants, or contractors will never pinpoint the real causes if they are seeking to protect themselves."

Professor Mohammad Shamsul Hoque, director of the Accident Research Institute (ARI) at Bangladesh University of Engineering and Technology (BUET), said that without identifying the responsible parties, no meaningful action can be taken.

"If the previous committee had addressed the real cause, the solution costs for repairing the faults would have been considered," he said. He recommended a two-stage investigation approach: first, to identify the cause and those responsible, and second, to ensure accountability.

Other engineers, including one with experience in Singapore's metro systems, expressed concerns that weak investigations may be used to conceal the truth. The first report did advise further analysis of the four potential causes by track and structural experts and the contractor of MRT 6's Contract Package 7.

JICA OFFERS SUPPORT

In response to a query from The Financial Express (FE) on Wednesday, the Japan International Cooperation Agency (JICA) Bangladesh Office said it is ready to provide all necessary support and cooperation to the Bangladesh government to complete the investigation and implement measures to ensure public safety.

FE had sought comments from the JICA Bangladesh chief representative on Monday, a day after the second incident in which a bearing pad fell from a pier, killing a pedestrian on the spot. The written reply was received on Wednesday.

JICA's statement read: "Any incident that claims human life is regrettable. JICA works closely with host governments worldwide to support local development that benefits communities. In this case, JICA is ready to provide all necessary support and cooperation to the Bangladesh government for completing the investigation and taking measures to ensure the safety of people."

FE contacted the JICA chief because MRT-6, the country's first metro rail along Dhaka's north-south corridor, was developed with Japan's technical assistance.

smunima@yahoo.com