【摘要】 2008年汶川8.0级地震中绵竹市板桥镇板桥学校液化破坏具有典型性,通过现场调查、高密度电法测试、波速测试、钻孔、探坑和室内试验等手段,研究了其地裂缝成因,分析了学校教学楼破坏机理以及液化土的特性。结果表明:①地裂缝是由液化而不是由次断层或破裂带引起;②板桥学校较周围房屋建筑震害严重,其破坏不是由于地震时振动惯性力所致,而是由于地基液化直接造成;③地下液化层为3.0～6.1 m的砂砾土,液化土不是地表喷出的细砂,地表喷出物与地下实际液化土差异显著;④以往认为砂砾土不会液化从而选择砂砾层作为持力层这一观点有误,需要重新认识。更多还原

【Abstract】 The liquefaction-induced damage of Banqiao School building following the 2008 Wenchuan Ms 8.0 Earthquake is typical,and the correlation between the ground fissures and the liquefaction is identified and mechanisms of the building damages as well as the characters of liquefied soils are investigated by field investigation and in-situ tests,such as multi-channels electric resistance test,spectral analysis of surface wave(SASW),dynamic penetration tests(DPT),borehole and trench,etc.The results show that:(1) the ground fissures are generated by the liquefaction rather than the secondary faults and ruptures;(2) Banqiao School building suffered more severe damages than its surrounding buildings from the liquefaction rather than inertia force of shaking during the Earthquake;(3) the subsurface liquefied soils are gravelly soils at the depth of 3.0-6.1m,which is different from the spouted fine sands;(4) the current knowledge is not true that the gravels are regarded as non-liquefiable soils,and a new procedure for liquefaction evaluation of gravelly soils is demanded.更多还原