JOHOR BARU, Oct 14 – An oversized billboard placed on the metal roof of a pedestrian bridge had probably contributed to it being blown off on Sunday afternoon. Two professors from Universiti Teknologi Malaysia (UTM) said yesterday they believed the incident, attributed to the “torsion effect, caused the metal roof to fly off”.
UTM director (structure) Prof Dr Mahmood Md Tahir said the billboard was not only too large, but was also not built according to specifications. “The person who designed the billboard failed to take into account the worst case scenario. It was put on top of the roof after the bridge was built. “There is nothing wrong with the steel structure of the bridge, but the billboard was too big and there were no holes on the surface of the billboard to disperse the force of the wind which was estimated to be more than 120kph on Sunday,” he said at the university yesterday.
This meant the wind force had sheared off the pin support in a twist-and-turn motion. Mahmood said he believed the freak storm did not just take out the metal roof along the Taman Perling-Pasir Gudang Highway, but there were similar incidents throughout the country. He said the pin support holding the billboard onto the roof could not withstand the force of the wind.
Prof Dr Mohammad Ismail, from the Faculty of Civil Engineering, said approval from an engineer must be obtained prior to installation of any billboard structure on top of a pedestrian bridge. He said a billboard along the highway was different from those on top of a bridge, as the former had back support which anchored the structure to the ground.
In the 4.30pm incident on Sunday, a lorry, two cars and a motorcycle were damaged after the 40m-long metal roof was ripped off by strong winds. Public Accounts Committee (PAC) chairman and Pulai member of parliament Datuk Nur Jazlan Mohamed said Sunday’s incident was a wake-up call for the authorities to act quickly in assessing and monitoring existing pedestrian as well as overhead bridges with billboards.
“The traffic flow along the Pasir Gudang Highway is heavy and the authorities need to immediately facilitate maintenance and checks as we do not want a repeat of what had happened on Sunday,” he said, adding that he was grateful no lives were lost in the incident.