粘性土中轴向受力桩的解

Solution of Axially Loaded Piles in Cohesive Soil

本文根据14根现场灌注桩(直径O.6～1.4m,入土深度16.7～42m)轴向荷载试验结果的分析,提出了粘性土地基中桩侧摩阻力与桩端阻力随其位移发挥的非线性理论模式(τ—s 曲线、q—s_t曲线),并考虑埋深、施工方法和土的性质的影响,由常规土工试验结果推求出模式的控制参数。用截面状态矢量法求解两根试桩所得结果同实测值对比,基本上是吻合的。因此,可以根据桩顶荷载—沉降曲线(P—s 曲线)比较合理地确定桩的轴向刚度和极限荷载。

According to the results of 14 cast in-situ test piles with 0.6～1.4m in diameter and 16.7～42m in embedded depth,this paper presents the nonlinear models of the mobilization of frictional resistance and point resistance with displacement(τ-s curve and q-s_l curve)in cohesive soil.Considering the influence of soil behaviour,embedded depth and construction method,the controlling parameters of each model can be determined by routine soil tests.Calculated results of two test piles,using the state-vectors method,are in good agreement with those measured in the field.Therefore,axial stiffness of piles(not a constant value)and ultimate load can all be determined rationally by the loading-settlement curve(P-s curve).