Government-backed investigators found that structural defects and inadequate construction standards caused schools to be the most vulnerable among all public buildings during last year's Sichuan earthquake.

Twenty-five of the 44 schools studied by a task force of university experts were determined to be heavily damaged and could not be restored. But among the 54 government buildings inspected, only seven sustained damage at the same level, the China Economic Weekly reported yesterday.

Nearly 70,000 people, including 5,335 students, were confirmed dead in the May 12, 2008 earthquake and about 18,000 people were reported missing. Around 3,340 schools need to be restored.

The task force report said schools were the most likely to collapse among the seven types of public buildings assessed, including factories and hospitals. The chief reason was structural defects, such as classrooms with wide interior spaces, big doors and windows and overhanging corridors.

But government buildings were mostly anchored on solid foundations and had the best performance in the magnitude-8.0 earthquake.

Lu Xinzheng, the writer of the report, said the heavy loss was also due to the anti-earthquake standards adopted in the design and engineering of school buildings. The standards used in many areas were too low because of budget limitations, said Lu, an associate professor at Tsinghua University's disaster prevention and relief construction institution.

Feng Peng, another member of the task force, pointed out that primary schools constructed in the early 1990s were built to higher standards and were less affected by the quake than schools built earlier.

The central government lifted the anti-quake standards for schools one level higher than those for ordinary buildings in July.

But the standards adopted by most cities were still not high enough due to construction costs.

An increase in each level of protection adds 20 to 30 percent to construction costs, experts said.

(Shanghai Daily May 26, 2009)