基于颗粒流的筒形挡土墙土压力研究  

Application of Particle Flow Code in Earth Pressures against a Cylindrical Wall

作　　者：陈国舟[1] 

机构地区：[1]中国矿业大学深部岩土力学与地下工程国家重点实验室,江苏徐州221008

出　　处：《土工基础》2014年第1期94-97,共4页Soil Engineering and Foundation

基　　金：国家重点基础研究发展计划(2012CB026103)

摘　　要：采用PFC3D颗粒流研究筒形挡土墙土压力随墙体位移的变化规律,分析达到主动极限状态时墙周土体的应力、孔隙率等因素的变化规律。结果表明:作用在筒形挡土墙上的土压力随着墙体位移的增加,土压力逐渐减小,最后趋于定值。达到极限平衡状态时,墙后土体中主应力偏转,形成了小主应力拱轨迹;高度h较小时,靠近墙体处形成了环拱效应,环向应力增大,孔隙率减小;随着高度h逐渐增大,环拱效应区域逐渐远离墙体,环拱效应减弱。将数值模拟结果与现有理论结果比较可知,现有理论中均未考虑空间拱效应,得到的结果与数值模拟结果存在差异。Based on the Distinct Element Method, the commercial program PFC3D was used to evaluate the earth pressures o[ sand acting on the cylindrical wall with various wall displacement magnitudes. The stress in the soil and the void ratio changes were studied when the soil reaches the active limit state. The results show that the earth pressures acting on the cylindrical wall decreases with a small displacement of the cylindrical wall. When the soil mass reaches the active limit state, the earth pres sures remain constant. A trajectory of the minor principal stress was formed due to the principal stress rotation induced by the wall-soil friction under the active limit state. The circumferential stress increases and the void ratio decreases as a result of the forming of an arching effect near the wall for a low h. With the increase of height, the effect of arching effect decreases. The comparison between the numerical simulation results and the theoretical solutions show that the theoretical solutions are not consistent with the numerical simulation results since the arching effect is not considered in all theoretical solutions.

关 键 词：颗粒流 筒形挡土墙 主动土压力 环拱效应 

分 类 号：TU476[建筑科学—结构工程]