黄土基坑斜直桩支护结构受力及变形特性模型试验研究  

Model test study on stress and deformation characteristics of inclined straight pile supporting structure in loess foundation pit

作　　者：曹卫平[1,2] 罗龙平 赵敏 席茂阳[1] CAO Weiping;LUO Longping;ZHAO Min;XI Maoyang(School of Civil Engineering,Xi’an University of Architecture and Technology,Xi’an Shaanxi 710055,China;Shaanxi Key Lab of Geotechnical and Underground Space Engineering,Xi’an Shaanxi 710055,China;College of Civil and Architecture Engineering,Xi’an Technological University,Xi’an Shaanxi 710021,China)

机构地区：[1]西安建筑科技大学土木工程学院,陕西西安710055 [2]陕西省岩土与地下空间工程重点实验室,陕西西安710055 [3]西安工业大学建筑工程学院,陕西西安710021

出　　处：《中国安全生产科学技术》2024年第1期141-147,共7页Journal of Safety Science and Technology

基　　金：陕西省自然科学基础研究计划项目(2019JM-006)。

摘　　要：为深入探究斜直桩支护的工作机理及变形特性,通过模型试验对比斜直桩和传统支护在开挖和降雨阶段桩顶位移、桩身弯矩及坑外沉降变化规律。研究结果表明:斜直桩受力及变形均小于悬臂和双排直桩,其极限挖深更大,对周边环境影响更小,其中内斜直支护性能最优。部分直桩改为斜桩可使受力更合理,除了受到弯剪还有拉压,有效提高支护刚度。降雨阶段下支护结构受力及变形增幅较开挖更大,还会引发土体塌陷、坑内外土体表面开裂等破坏。研究结果可为斜直桩黄土基坑施工风险防控提供参考。In order to deeply explore the working mechanism and deformation characteristics of the inclined straight pile support,the changes of pile top displacement,pile bending moment and settlement outside the pit between the inclined straight pile and the traditional support during the excavation and rainfall stages were compared by model tests.The results show that both the force and deformation of the inclined straight pile are smaller than those of the cantilever and double row straight pile,its ultimate excavating depth is larger,and the influence on the surrounding environment is less,among which the internal inclined straight support has the best performance.Changing part of the straight pile to inclined pile can make the force more reasonable,in addition to bending shear,there are tensive compression,which effectively improve the support stiffness.During the rainfall stage,the stress and deformation of the support structure increase more than that of excavation,and it will also cause soil collapse,surface cracking of soil inside and outside the pit,and other damage.The research results can provide reference for prevention and control of risk in construction of inclined straight pile loess foundation pits.

关 键 词：斜直桩 黄土基坑 模型试验 降雨 

分 类 号：X947[环境科学与工程—安全科学] TU743[建筑科学—建筑技术科学]