港口工程中非均质层状地基承载力计算方法

Methods for estimating bearing capacity of layered foundations in harbor engineering

在深水码头、防浪堤等大型港口工程建设中常常会遇到构筑物下覆地基由非均质的层状土构成的情况。对于这类非均质层状地基,我国港口工程地基规范推荐采用Hansen 61公式、Hansen 69公式和Sokolovskii数值解法3种方法计算地基的极限承载能力。然而,工程实践中由这3种方法计算得出的地基极限承载力数值往往有较大的差别。考虑到规范的继承性,基于牛顿迭代法,针对3个理论计算公式编制了计算程序,根据长江口深水治理二期工程地质实测资料,运用该计算程序对该地区地基的极限承载能力进行了计算比较。计算结果表明,对于非均质层状地基,在相同地质条件、相同荷载条件下Sokolovskii数值解法得到的承载力数值最大,Hansen 69公式得到的承载力数值最小。

In Harbor Engineering, it is often the case that subsoil consists of layered soils. In China, Hansen 61＇s methods, Hansen 69＇s methods and developed Sokolovski methods were recommended by the code to estimate the ultimate bearing capacity of layered foundation. However, in practice the ultimate bearing capacities of layered foundations predicted by the three methods are different from each other. Considering inherits of the codes, a calculation program has been compiled using Newton iteration methods to solve the expressions presented in the codes. Then, basing on the geotechnical information in the Yangtze River mouth region, the ultimate bearing capacities of layered foundations have been computed by the program and the predictions from three methods have been compared each other. The results show that under the same geotechnical conditions and similar loading conditions, the developed Sokolovski methods shall provide the largest bearing capacity values among three methods; while the bearing capacity value from Hansen 69＇s methods shall be smallest.