Two substandard steel samples linked to collapsed Bangkok building

The inspection came after the 30-storey building in Bangkok’s Chatuchak district collapsed due to an earthquake on Friday afternoon, resulting in many injuries, fatalities and missing persons.

The Industry Ministry sent 28 steel pieces from the wreckage to the Iron and Steel Institute of Thailand for inspection, categorised into seven samples: 32mm, 25mm, 20mm, 16mm, and 12mm deformed steel bars, wire ropes, and steel bars.

The inspection took more than six hours and found that two samples were substandard, coming from the same company whose factory in Rayong province was ordered to close in December last year, according to the ministry’s working team.

The working team chief  Thitipas Chotedechachainan said two substandard samples were 32mm and 20mm deformed steel bars. The 32mm deformed steel bars failed to meet the force-receiving value standard, while the 20mm bars failed to meet the mass-per-metre standard, she explained.

However, she noted that these samples are not sufficient to conclude that they were responsible for the building collapse. The Thai Industrial Standards Institute (TISI) will collect more samples and inspect the factory to determine whether it has illegally produced or transported steel.

If the order is violated, strict measures will be taken, she warned.

Kitjapat Phuvoravan, a member of the Engineering Institute of Thailand, explained that 32mm deformed steel bars are often used in assembling building column bases for casting cement. If these bars fail to withstand the force exerted by the building structure, they could increase the risk of collapse, he said.

He further stated that 20mm deformed steel bars are commonly used to construct bases or small pillars, adding that failure to meet the mass-per-metre standard would lead to inaccuracies in other measurements and pose risks to the building.

Steel structures are a crucial component of a building’s foundation, but they are not the sole factor that could contribute to a collapse. Other elements, such as construction design and the quality of cement, also play a role, he noted.

He believes that TISI will collect more samples for inspection, particularly focusing on cement.

Ekniti Romyanon, Inspector-General of the Industry Ministry, stated that sample collection from the State Audit Office building was limited due to challenges in rescuing victims and accessing the scene.

He explained that negotiations with the office to obtain samples took considerable time. However, he confirmed that the ministry would do its utmost to determine the reasons behind the collapse.