非均质地基中群桩竖向荷载沉降关系分析

运用剪切位移法计算了桩轴向荷载传递因子.对于桩端采用线性的荷载传递函数,推导了基于弹塑性模型的单桩竖向荷载沉降的解析解.分析过程中考虑了土体强度沿深度线性变化的特性和桩土间的滑移现象,因此更符合大部分土体的实际性状.在此基础上,建立了考虑桩土滑移的桩-桩相互作用系数的计算公式,并将上述方法应用于群桩的分析,获得了群桩的荷载沉降特性.该分析方法克服了目前应用较多的弹性理论方法夸大桩土相互作用的缺点,单桩和群桩的荷载沉降曲线的分析结果和实测数据吻合,证明了该方法的合理性.

Analysis of settlements of vertically loaded pile groups in non-homogeneous soil

The shaft load transfer factor is calculated through the shear displacement method. Based on linear load transfer function to pile-base soil, using the elastoplastic model, a set of analytical equations for the settlement of vertically loaded pile are obtained. The theoretical model considering the strength of soil varying along the depth and the slip between pile and soil will be more realistic in practice. It is extended to determine the interaction factor between two piles and application to the analysis of pile groups is also presented. The proposed approach overcomes the limitation of elastic theory. The validity of the proposed method is verified through the comparisons of finite element method and field tests for the settlements of single pile and pile groups. General good agreement lends confidence in the applicability of the proposed method to practical problems.