Under surface support missing
A radar scan yesterday didn't detect any cavity that could have caused the collapse of Rama IV Road on Sunday, but it did show that the spot had no ferro-concrete support.
Deputy Bangkok Governor Theerachon Manomiapibul led the inspection, using a rented ground-penetrating radar (GPR) that could look 2.5 metres beneath the surface to check the concrete structure for the 400-metre stretch between Lumpini Tower and Wireless intersection.
The test didn’t turn up anything abnormal and the road had a ferro-concrete support underneath except at the sinkhole site.
The Bangkok Metropolitan Administration will investigate whether the contractor hired in 2003 for road repair did a substandard job.
The city will also have the Engineering Institute of Thailand help find the cause of the cave-in, as an initial search has found no damage to the sewer or water mains that run under the road. The result should be released in two weeks.
The city will also consider buying a Bt6-million GPR for use in surveying roads for infrastructure development, Theerachon said.
