活动门试验中土体变形及破坏规律  

The soil deformation and failure features in trapdoor tests

作　　者：李尧[1] 董星 陈厚先 郭张龙 杜旭超 LI Yao;DONG Xing;CHEN Houxian;GUO Zhanglong;DU Xuchao(School of Highway,Chang'an University,Xi'an 710064,Shaanxi,China)

机构地区：[1]长安大学公路学院,陕西西安710064

出　　处：《山东大学学报（工学版）》2023年第5期92-102,共11页Journal of Shandong University（Engineering Science）

基　　金：国家自然科学基金资助项目(52078045);长安大学中央高校基本科研业务费专项资金资助项目(300102213205)。

摘　　要：为研究活动门试验中土体变形和破坏规律,采用黄土相似材料,开展不同埋深比(埋深与活动门宽度之比)下的活动门试验,监测不同埋深土体在活动门下降过程中的内部位移和地表位移,结合离散元模型分析土体变形及破坏规律的埋深分界线。试验监测数据表明,随埋深比增大,变形更集中于活动门上方更小范围,土体变形破坏规律存在显著差异;活动门下降过程中裂缝大致沿相对位移等值线发展,其发展模式与砂土活动门试验中剪切带发展规律存在一定差异。试验和离散元模拟结果表明:埋深比2.0~2.5为土体变形及破坏规律的埋深分界线;基于所得土体体积变化特征,提出活动门试验中松动区高度的计算方法。To study the internal deformation and failure feature in the trapdoor tests,a series of tests were carried out with loess similarity material under different depth ratios(soil depth divided by trapdoor width).The internal soil displacement at different depths and surface soil displacement were measured during the lowering of the trapdoor.Combined with distinct element modeling,the critical depth ratio that divides soil deformation and failure features was analyzed.Measured test data showed that with increasing depth ratio,the deformation of soil was more concentrated above the trapdoor,and there were significant differences in deformation and failure characteristics of the soil.With the lowering of the trapdoor,the cracks developed along the contour,but the development patterns were different from the patterns of the shear band developed in the trapdoor test on sand.Test and simulation results indica-ted that the critical depth ratio that divides soil deformation and failure features was 2.0-2.5.Based on obtained characteristics of soil volume changes,a calculation method for determining the height of loosened zone was proposed.

关 键 词：活动门试验 黄土相似材料 内部位移 裂缝 地表沉降 离散元模拟 松动区高度 

分 类 号：TU433[建筑科学—岩土工程]