《Journal of Geotechnical and Geoenvironmental Engineering》杂志刊登“粘土中钻孔桩的桩侧阻力”

作者：Tanusree Chakraborty, A.M.ASCE; Rodrigo Salgado, F.ASCE; Prasenjit Basu, A.M.ASCE and Mônica Prezzi, A.M.ASCE

刊物：《Journal of Geotechnical and Geoenvironmental Engineering》，139卷第4期，548–563页

关键词：钻孔桩；非挤土桩；桩身强度；粘土；数值模型分析；双面塑性

摘要：目前的研究基于高级粘土双面塑性本构模型利用有限元分析对粘土中钻孔桩的极限侧摩阻力进行了量化研究。本研究中使用能够模拟多轴荷载条件下粘土的力学反应的粘土本构模型，并预测了在小大应变下排水和不排水的变形行为，得到了在非常大剪切应变下强度朝着一个残余数值的下降的结论。用一维有限元模拟了粘土钻孔桩在不同的初始应力，不同的超固结比，以及介于极限状态和最小残余内摩擦角的不同值下的必要的安装阶段和加载过程。在模拟的基础上，提出了可以用于计算粘土中钻孔桩桩侧阻力的桩摩擦系数的计算方程。该方程的预测值与从钻孔桩现场载荷试验中得到的试验数据结果比较吻合。

Shaft Resistance of Drilled Shafts in Clay

Authors: Tanusree Chakraborty, A.M.ASCE; Rodrigo Salgado, F.ASCE; Prasenjit Basu, A.M.ASCE and Mônica Prezzi, A.M.ASCE

Journal:《Journal of Geotechnical and Geoenvironmental Engineering》，Volume 139, Number 4,548–563

Key words: Drilled shaft; Non-displacement piles; Shaft capacity; Clay; Numerical modeling and analysis; Two-surface plasticity

Abstract: The current study examines and quantifies the limit shaft resistance of drilled shafts installed in clay through finite-element analyses that use an advanced two-surface-plasticity constitutive model for clay.The clay constitutive model used in this study reproduces the mechanical response of clays under multiaxial loading conditions, predicts both drained and undrained behavior at small and large strains, and captures the drop in strength toward a residual value at very large shear strains. One-dimensional finite-element analyses are performed to simulate the essential stages of the installation and loading of drilled shafts in clay for different initial stresses, different over consolidation ratios, and different values of the difference between the critical-state and the minimum residual friction angles. On the basis of these simulations, equations for the shaft friction coefficient are proposed that can be used in the calculation of the shaft resistance of drilled shafts in clay. Predictions using the proposed equations compare well with the data derived from different field pile load tests on drilled shafts.

原文链接：http://ascelibrary.org/doi/abs/10.1061/%28ASCE%29GT.1943-5606.0000803