Dr. Amorn Recommends Three-Point Inspection Following Lithium Battery Truck Explosion and Expressway Fire
A lithium battery truck explosion on Bangkok's Burapha Withi Expressway has prompted structural engineers to recommend urgent inspections of the 30-year-old prestressed concrete bridge, particularly its heat-sensitive internal wiring system
On May 4, 2025, a lithium battery-carrying truck exploded and ignited a fire on Burapha Withi Expressway at kilometer 40, causing structural damage. Prof. Dr. Amorn Pimmanmarch, president of the Structural Engineers Association of Thailand and engineering professor at Kasetsart University, revealed that the elevated expressway structure is a prestressed concrete construction built using precast segments connected and secured together with prestressing wires. Construction began in 1995, making the structure 30 years old.
Regarding the impact of fire and heat on the structure, Prof. Dr. Amorn explained that heat and fire can cause concrete and reinforcing steel to deteriorate depending on the duration of exposure. While concrete structures generally resist heat better than steel structures, this particular structure contains internal prestressing wires, making it relatively sensitive to heat damage.
He initially recommends inspecting the structure in three areas: (1) the duration the structure was exposed to fire—longer exposure means greater impact; (2) the condition of concrete damage such as spalling and surface deterioration; and (3) whether heat affected the prestressing wires and internal reinforcing steel.
Damage assessment can be conducted through various engineering methods, including extracting concrete samples for testing, measuring tension in prestressing wires, and examining deformation of reinforcing steel.
Prof. Dr. Amorn added that the responsible authorities should urgently conduct these inspections to ensure safety for expressway users and those traveling on roads beneath the elevated structure.
