Dhaka, Oct. 26 -- After the fatal metro rail accident, questions are mounting over how a bearing pad -- which supports viaducts weighing hundreds of tonnes -- could fall off again, just 13 months after a similar incident.

Even the Road Transport Advisor Fouzul Kabir Khan, raised the question, noting that last year's accident caused no casualties but exposed design vulnerabilities that remain unresolved.

Experts explain that bridge or flyover bearing pads are not mechanical bearings as used in vehicles, but thick layers of neoprene or natural rubber designed to absorb vibration between a pier and viaduct joints. Some pads are reinforced with internal steel plates and can weigh over 100kg.

Engineer Moniruzzaman, who has long worked on br...