摘要
刚性挡土墙后土体在墙土间摩擦力作用下主应力会发生一定程度偏转,即土拱效应现象,使得土压力呈非线性分布。为考虑土拱效应对主动土压力分布的影响,基于水平微分土层法,假设墙后土体主应力偏转迹线呈抛物线形,定义水平微分土层侧压力系数,建立并求解水平微分土层平衡方程,获得主动土压力强度分布函数,进而求取主动土压力合力数值及其作用点位置表达式。研究结果表明:随着δ/φ逐渐增大,土拱效应逐渐增强,主动土压力呈非线性分布,由上至下先增大后减小;合力作用点高度与δ和φ之间均呈正相关关系,随着土拱效应的增强而升高;与模型试验及现有理论解析模型对比表明,关于主动土压力分布和合力作用点高度的计算误差最小,证明了方法的准确性和适用性。
The principal stress of soil behind rigid retaining wall will rotate due to the friction on the contact surface between soil and wall. The rotation process of principal stress,called arching effect,can result in non-linear distribution of earth pressure. To estimate the value of active earth pressure considering arching effect,a parabolic arch is assumed as the rotation trace of minor principal stress. The distribution function of active earth pressure is deduced by definition of lateral pressure coefficient and solution of the equilibrium equation of horizontal differential layer. Based on the distribution function,the value and the point of resultant force of active earth pressure are derived. The results indicate that: the arching effect enhances gradually with the increase of δ / φ and active earth pressure present a non-linear distribution; the point height of resultant force shows a positive correlation with δ andφ; compared to the model test and other theoretical methods,estimation results of the active earth pressure and its point height using this method has the minimum error,which proved the correctness and applicability of this method.
出处
《科学技术与工程》
北大核心
2016年第20期238-242,252,共6页
Science Technology and Engineering
基金
贵州省科学技术联合基金项目(黔科合J字LKM[2011]16号)资助
关键词
挡土墙
主动土压力
土拱效应
主应力偏转
抛物线形
retaining wall
active earth pressure
arching effect
principal stress rotation
parabolic arch
