邓肯-张模型有限元分析路堤沉降实用方法

Practical method for FEM analysis of embankment settlement with duncan-chang model

有限元法是计算路堤沉降常见的数值计算方法,但其模型参数一般需要做三轴排水试验确定。为了使该法更为实用,对已有的Duncan-Chang模型中切线弹模简化确定法进行了误差分析,提出了具体的修正系数;基于土体的K0状态条件,给出了一个切线泊松比近似计算公式,对砂性土和粘性土均可适用。实例计算表明:所提出的方法对缺乏三轴试验资料,但又需进行有限元计算沉降的一般道路工程,具有一定的借鉴意义和参考价值。

Finite element method is a familiar method in the calculation of embankment settlement,but it has difficulties in deciding model parameters. Generally,this needs doing triaxial drained test. In order to make this method be practical,some error analyses,which are concerned about the existing simple method for determining tangential elastic modulus of Duncan-Chang model,are done and related modified coefficient is also brought forward. Furthermore,an approximate formula for determining tangential Poisson ratio,suitable for both sandy and cohesive soils,is given according to the K0 status of soils. Example shows that the above methods have definite reference value in common road engineerings which need settlement calculation with FEM but lack of triaxial test materials.