软基上弹性基础板简化分析方法及适用性

软土地基上水闸、泵站底板的结构计算通常采用＂截条法＂简化成平面应变问题考虑,这种简化分析结果不能完全表征底板的受力特性。本文对半无限空间上不同基础模量条件下不同长宽比的弹性基础板的受力变形特性用半解析有限元法进行了分析,同时进行了相同力学参数条件下的平面应变分析。两者比较表明：当基础板两个方向长度相当时,用平面问题求解得到的最大拉应力比按空间问题求解得到的结果大33%。同时随着地基刚度的加大,增大的比值也加大。

Adaptability of a simplified analytic method for elastic base-board on soft foundations

A method that cut out a beam with unit width from a plate is usually applied to structure analysis of base plate of sluice and pump station on soft foundation. It should be pointed out that the stress and strain characteristics of this kind of plate obtained from this simplified analytic method can not be expressed entirely. In this paper a semi-analytic FEM is used to analyze the behavior of force-bearing and deformation of elastic base-board with different ratios of length to width and different elastic base modulus in semi-infinite space. The plane strain analysis under the same mechanical parameters is also carried out. The comparison shows that the maximum tensile stress obtained from the plane strain algorithm is 33% larger than that obtained from the space algorithm. The ratio is increased with the ratio of stiffness.