The collapse of the Al-Jamal flyover on the Riyadh-Dammam highway was caused by negligence, a government-appointed technical committee has found.

The committee, comprising academics from King Fahad University of Petroleum and Minerals, recently completed its investigation into the incident and sent its report to Minister of Transport Jabara Al-Seraisry.

The committee found that due to lack of maintenance, rust and corrosion had set in weakening the concrete structure that collapsed on Dec. 20 but caused no harm.

The committee had conducted various technical and scientific tests at the site, a source said.

“The committee filed a comprehensive report about the reasons for the collapse with the Ministry of Transport, which ends its role in the investigation,” the source said.

“The committee followed routine procedures, starting with a visit to the location, taking samples and analyzing them,” the source said.

The source said the investigation showed there was nothing wrong with the design and building of the 30-year-old flyover. The problems had arisen because of the lack of maintenance.

Members of the committee had completed the investigation out of a sense of national duty and not for any financial gain, according to the source.

The bridge consists of two symmetrical halves, with each side fixed onto a concrete frame in the middle. The collapse occurred on one side close to the supporting frame in the middle. The other side was intact.

Othman Subhi Al-Shamrani, assistant professor of civil engineering at the department of architecture and planning at Dammam University, who had examined the bridge earlier, said the collapse might have been caused by water accumulating inside the concrete structure because of a lack of drainage. This may have caused the metal to rust and weaken, he said.

Al-Shamrani said members of the engineering faculty who examined the bridge had found rust and corrosion in the iron inside the structure. He said the design had not taken into account the effect of rain, which caused the formation of a thick layer of mud around the structure.