基于突变理论的液化评估方法

作为众多突变类型的一种形式,尖点突变模型由于其优良的性质而广泛应用于生物学和社会科学,近年来又有越来越多的学者用尖点突变模型来研究工程实际问题。本文基于地震液化的基本机理和突变理论的特点,以土体的抗液化能力和土体得到的地震能量为控制变量,以孔隙水压力发展为状态变量,建立了地震诱导的孔隙水压力发展模型。宏观震害调查结果和本文的计算结果对比表明,本文建议的方法方便、可靠,是一种理想的液化评估方法。

Estimation of liquefaction based on catastrophe theory

The cusp catastrophe model,a type of diverse catastrophe models which were created by Tom,is a typical and useful tool widely applied in biology,social science,and recently in engineering.In this paper,equations to express the pore water pressure induced by earthquake in a sandy soil body are constructed and analyzed.The formulas are built with capability of soil's anti-liquefaction potential and received energy in an element in an earthquake as two control variables and with pore water pressure increment induced by librations as a state variable for the cusp catastrophe model.Then the parameters in the equations are determined by data from liquefactions and un-liquefactions phenomenon in situation many earthquakest taken place all over the world in the past decades.In the end, comparison between in situation macroscopical liquefaction phenomenon induced by earthquake and calculated results by the proposed method is made and accordingly verifies the proposed method.The results show that the model can be conveniently and reliably used to correctly estimate sand liquefaction potential in practical engineering.