Xinhua News Agency, Gansu Jishi Mountain, December 24 (Xinhua) -- Experts explain Jishi Mountain 6 in detailMass collapse of Class 2** farmhouses.
Xinhua News Agency reporters Jia Zhao and Wang Mingyu.
At 23:59 on December 18, an earthquake with a magnitude of 6Level 2, with an epicenter depth of 10 kilometers, raided Jishishan County, Gansu Province, and as of 8 o'clock on the 22nd, a total of 117 people have been killed and 781 injured, nearly 150,000 houses collapsed.
6.Why did Level 2** cause a large number of houses to collapse?How to further improve the seismic performance of rural self-built houses?On the 24th, the relevant person in charge of the Gansu Provincial Department of Housing and Urban-Rural Development responded to the above questions.
Wang Yong, deputy director of the Gansu Provincial Department of Housing and Urban-Rural Development, said that the epicenter is very shallow and the thrust type is larger. At the same time, Jishishan County is located on sedimentary strata, at the junction of the Loess Plateau and the Qinghai-Tibet Plateau, on the western edge of the Loess Plateau. Relevant studies have shown that the occurrence of ** in the Loess Plateau will have a more significant site amplification effect, resulting in greater surface destructive power.
According to the Ministry of Emergency Management's "Gansu Jishi Mountain 6Level 2 ** Intensity Map", the maximum intensity of this ** reached 8 degrees, with an area of 331 square kilometers, mainly involving Dahejia Town, Liuji Township, Shiyuan Town, Liugou Township and other hard-hit areas in Jishishan County.
Wang Yong said that this maximum intensity exceeds the 7-degree fortification intensity of Jishishan County determined in the relevant annex of the national standard "Code for Seismic Design of Buildings", and at the same time, rural housing is mainly self-raised, self-built and self-used, and the seismic performance is uneven, which is the main reason for the collapse of houses.
*After the incident, the Gansu Provincial Department of Housing and Urban-Rural Development organized various forces to go to the disaster area to conduct an emergency assessment of the affected houses, and the assessment has been completed.
Gansu Provincial Department of Housing and Urban-Rural Development Village and Town Construction Division Director Ma Xiaodong introduced, from the assessment of the situation, most of the collapsed and seriously damaged farmhouses were built earlier, with villagers building their own partial houses, auxiliary houses, this kind of houses are mostly civil or brick and wood structures, load-bearing walls are earth walls or brick walls, the parts connected by the wall and the wooden frame are not firm, the integrity is not strong, and the performance of resisting high intensity is weak.
In recent years, Jishishan County has promoted the transformation of dilapidated houses in rural areas, solved the safety problems of the people's main residential houses, and subsidized those who passed the acceptance. Ma Xiaodong said that these newly built or rebuilt farmhouses basically did not collapse as a whole, and the main problems were wall cracks and flashing.
In addition, although some farmers have built new houses, they prefer to live in old houses with ondols in winter, which is more convenient and economical to heat than new houses with heating stoves. The assessment found that many** was caused by living in an old house.
Experts said that the disaster highlighted the urgency of improving the seismic performance of rural houses.
Wang Yong and others pointed out that improving the seismic performance of rural housing requires many efforts, and it is necessary to further popularize and enhance the awareness of rural households to build earthquake-resistant houses, strengthen the technical guidance and construction management of rural houses to resist earthquakes, promote the use of building materials with better seismic performance, and train qualified rural construction craftsmen.
Experts also suggested that in the project to improve the quality and safety of rural houses, we should increase support for the seismic renovation of rural houses in remote areas, and continue to improve the seismic capacity of rural houses. (ENDS).