【摘要】 合理假定地震液化效应的不确定性主要来源于地面最大水平加速度,借用中国华北地区地震动加速度衰减关系量化CSR的变异性,结合对地震液化现场案例的统计分析构建CSR的概率密度函数;同时,以世界范围内19次中强震106个场地的CPT液化案例为基础,通过LOGISTIC方法构建不同概率水平时的地基抗液化强度CRR强度曲线,并以此导出CRR的概率密度函数;进而通过一次二阶矩法构建地基液化可靠性评价模型,同时导出地基液化概率函数,便于工程应用。工程实例与理论对比分析均表明,评价方法简洁可行、评价结果合理,可作为规范方法的有益参考。更多还原

【Abstract】 In the sense that the horizontal peak ground is the dominant factor producing the CSR variation,the empirical acceleration attenuation law in Northern China area is employed to deduce the PDF and the statistics for CSR based on the statistic analysis of the cone penetration test data from 19 strong earthquakes liquefaction site around the world.Through logistic model,based on the above data from liquefaction site,the CRR curves with various liquefaction probabilities are developed,and consequently the PDF for CRR is also deduced according to the CRR curves.Then,the first order and second moment method is employed to establish a reliability-based evaluation of liquefaction model.Furthermore,in order to be conveniently applied in the engineering practice liquefaction probability function is founded.Through theoretical and contractive analyses on a representative sample,the estimation veracity of the developed CPT model goes near to the engineering examples which indicate the reliability and the simplicity of the method.Thus,it can be used as a significant supplement of the code.更多还原