嵌岩桩水平承载力计算方法的讨论和分析

Analysis and discussion of calculation methods for rock socketed piles under lateral load

基于桩-土受力变形特性,分析了嵌岩桩的承载力。在水平力作用下,弹性长桩与较长的嵌岩桩的受力变形特性极其相似。弹性长桩的假想嵌固点与较长的嵌岩桩的桩下端实际嵌岩点均被认为不会产生水平位移和转角,而假想嵌固点的位置呈现有分段突变特性。以2个拐点为界,将水平力-位移(即H0-y0)试验曲线分为3个区段,得到H0-y0试验折线关系,再应用m法拟合进行计算。计算结果表明:桩顶大位移工况的结果均与试验值吻合良好;当水平力大于第2拐点后,A^#桩顶水平位移受桩下端嵌岩的主导作用,其位移变化率不升反降。该结果可供相关问题计算分析时参考。

From the view of the pile-soil stress and deformation characteristics, it is very similar that the characteristics of elastic long piles and long rock socketed piles under the horizontal force, are very similar, which can be explained in detail that horizontal displacement and rotation both to the former hypothetical build-in point and to the latter actual build-in point won't be produced. Furthermore, the hypothetical build-in point shows the location of a segmented mutation. The test curve of lateral force-displacement or called ‘H0-y0’ was divided into three sections by two inflection points,‘H0-y0’ test broken line can be obtained and its relationship has been tested with ‘m’ values, and then ‘m’ method was applied to calculate and deal with it, the final calculation results including the results of pile top with large displacement are in good agreement with the test. It is also found by the test that when the lateral force is greater than the second inflection point, the lateral displacement at the top of pile No. A is dominated by the rock socket at the bottom of the pile, and the rate of displacement change does not increase but decreases, all the abovementioned results can be as a reference in the calculation and analysis of related problems.