摘要
抗滑桩等非连续支挡结构在边坡工程中依靠土拱效应安全经济地发挥支护功能。鉴于不同类型砂土的力学性质差异较大,为揭示密砂与松砂土质边坡抗滑桩桩间水平土拱机理与演变规律,采用离散元方法(DEM)模拟支挡砂土水平土拱的成拱过程。在传统力链分析的基础上,提出通过筛选高应力颗粒来研究土拱的形成过程,进一步从细观角度对不同工况土拱效应进行分析,以揭示“应力拱”和“位移拱”的演化过程。研究表明:密砂和松砂中的水平土拱的动态演变过程均表现为3个演化阶段,分别对应于密砂和松砂的剪切性状,即应变软化和应变硬化现象,揭示了砂土边坡桩间土拱效应的演变规律。此外,讨论了宏-微观DEM模拟参数对土拱形成过程与土拱效应性能的影响,结果表明拱跨对于荷载传递效率的影响最大。
The non-continuous retaining structures such as anti-slide piles rely on the soil arching effects to provide support safely and economically in slope engineering.Considering the significant differences in the mechanical properties of sands,to reveal the mechanism and evolution patterns of horizontal soil arching between piles in sand slopes,the discrete element method(DEM)is used to simulate the formation process of horizontal soil arching.On the basis of the traditional force chain analysis,it is proposed to study the formation process of soil arching by screening high stress particles.Furthermore,the analysis of the soil arching effects under different conditions from a microscopic point of view is conducted to reveal the evolution process of“stress arching”and“displacement arching”.The results demonstrate that the dynamic evolution of horizontal arching in both dense and loose sands can be divided into three evolutionary stages,corresponding to the shear behaviors of the two sands,i.e.,strain softening and strain hardening phenomena,which reveals the evolution patterns of the soil arching effects in the sand slopes.Additionally,the influences of macro-micro DEM simulation parameters on the arching process and performance are discussed.The results indicate that the arching span has the greatest impact on the load transfer efficiency.
作者
王涛
姬建
WANG Tao;JI Jian(College of Civil and Transportation Engineering,Hohai University,Nanjing 210024,China;Key Laboratory of Ministry of Education for Geomechanics and Embankment Engineering,Hohai University,Nanjing 210024,China)
出处
《岩土工程学报》
EI
CAS
CSCD
北大核心
2024年第8期1742-1752,共11页
Chinese Journal of Geotechnical Engineering
基金
国家自然科学基金项目(U22A20594,52079045)。
关键词
砂土边坡
抗滑桩
水平土拱效应
作用机理
动态演变
离散元方法
sand slope
anti-slide pile
horizontal soil arching effect
action mechanism
dynamic evolution
discrete element method
