考虑土体结构性损伤的沉桩挤土效应解析分析

Analytical solutions of squeezing effect caused by pile-driving in soil with structural damage

根据土塑性力学基本原理,采用简化的线性软化模型并考虑土的结构性损伤影响,推导出沉桩时产生的挤压应力的空间解析解,并在此基础上分析了土体具有不同的损伤程度时沉桩产生的挤压应力和极限扩张压力的空间分布规律。同时,采用 Henkel 孔隙水压力公式,进一步分析孔隙水压力的发展规律,该解析解可以弥补经典圆孔扩张理论在沉桩应用中的不足,能更好地揭示沉桩时的挤土机理。

Based on the fundamental principles of soil plastic mechanics,the formulas calculating the squeezing stress in the expansion of cylindrical cavity during pile-driving are deduced taking the soil structural damage into account.The three-dimensional distributions of the squeezing stress and the terminal expansion force during pile-driving are analyzed.So the shortcoming of the classical cylindrical cavity expansion theory can be overcome.The mechanism of soil squeezing during pile-driving will be revealed more clearly.Finally,the pore pressure due to pile-driving is discussed based on HenkeI's equation.