墙后有限宽度无黏性土主动土压力试验研究  

Experimental study on active earth pressure of cohesionless soil with limited width behind retaining wall

作　　者：杨明辉[1] 戴夏斌 赵明华[1] 罗宏[1] 

机构地区：[1]湖南大学岩土工程研究所,湖南长沙410082

出　　处：《岩土工程学报》2016年第1期131-137,共7页Chinese Journal of Geotechnical Engineering

基　　金：国家自然科学基金项目(51278184;50708030);教育部新世纪优秀人才支持计划(NCET-13-194)

摘　　要：针对无黏性土体,开展了刚性挡墙平动、绕墙底转动和绕墙顶转动3种墙体主动变位模式情况下墙后有限宽度土体土压力试验。通过观察墙后不同宽度土体的破坏过程及对土压力的全程量测,对其破坏模式及土压力分布规律进行了探讨。试验结果表明,墙后有限宽度土体的破坏面为一连续曲面,随着墙后土体宽度的增加,土体破坏面逐渐向外侧偏移,最终趋于某一固定位置,但始终位于库仑破坏面内侧。土压力值监测表明,库仑土压力理论并不适用于有限宽度土体。当填土宽度为有限宽度时,土压力值小于库仑主动土压力值,其差距随土体宽度减小而逐渐增大。当墙体平动时,土压力值沿墙高先增大后减小;墙体绕墙底转动时土压力值则呈线性增长趋势;而当墙体绕墙顶转动时,在挡墙上部出现了明显的土拱效应。An experiment is conducted to study the active earth pressure of cohesionless soil with limited width behind retaining wall in three different modes, which are translational motion, rotation around bottom and rotation around top. In the experiment, the failure modes of the soil and the distribution of the active earth pressure with different backfill widths are observed. The results show that the failure surface of the limited-width soil behind the retaining wall is a continuous one, which continuously moves to the outside and approaches a fixed position with the increase of the backfill width. But the failure surface of cohensionless soil is always located inside the Coulomb failure surface. Furthermore, the actual active earth pressure is less than that calculated by the Coulomb＇s theory, and the difference increases with the decrease of the backfill width, which indicates the Coulomb＇s theory is not applicable anymore for the backfilled soil with limited width. In addition, the motion patterns of retaining wall have great effects on the distribution of the active earth pressure. When the motion of retaining wall is translational, the earth pressure increases to a peak value first, then decreases with the increase of depth; when the retaining wall is rotating around the bottom, the earth pressure linearly increases with the increase of depth; and when it is rotating around the top, a significant earth arch effect is observed at the upper part of the retaining wall

关 键 词：主动土压力 有限土体 刚性挡墙 破坏模式 主动变位模式 

分 类 号：TU411[建筑科学—岩土工程]