不同水因素影响下土石混填体承载力学特性研究  

Research on the Bearing Mechanical Characteristics of Soil-rock Mixed Fill under Different Water Factor Effects

作　　者：杨泽华[1] 张高才[2] 江帆 罗佳湘 张超 YANG Ze-hua;ZHANG Gao-cai;JIANG Fan;LUO Jia-xiang;ZHANG Chao(School of Architecture and Environmental Engineering,Zhengzhou Technical College,Zhengzhou 450121,China;College of Civil Engineering,Hunan University,Changsha 410082,China;Faculty of Land Resources Engineering,Kunming University of Science and Technology,Kunming 650093,China;College of Civil Engineering,Hunan University of Science and Technology,Xiangtan 411201,China)

机构地区：[1]郑州职业技术学院建筑与环境工程学院,郑州市450121 [2]湖南大学土木工程学院,长沙市410082 [3]昆明理工大学国土资源工程学院,昆明市650093 [4]湖南科技大学土木工程学院,湘潭市411201

出　　处：《公路》2024年第6期28-35,共8页Highway

基　　金：国家自然科学基金资助项目,项目编号51378198。

摘　　要：土石混填体如坝体或路堤必然受到复杂自然环境的影响,其竖向承载力学特性是工程建设关注的焦点。采用西南山区土石料按相似比理论制作级配良好的土石混填路堤模型,布设临近路堤中心线(“左列”)、加载板中心线(“中列”)和邻近路堤临空坡体(“右列”)的3列等间距土压力盒,使其分别处于初始环境状态(模型A)、降雨饱和环境状态(模型B)和干湿循环状态(模型C),采用分级加载程序进行模型承载试验和数值模拟。研究结果表明:模型A和模型C具有良好的结构性,p~s曲线有明显拐点,破坏有突发性,模型B荷载沉降关系曲线无拐点,相同荷载作用下模型C沉降量介于模型A和模型B之间;同层条件下加载板中心土压力比相邻土体大,“左”列约束大于“右”列使不同环境状态下土石混填路堤竖向应力扩散具有不对称性,“左”列土压力大于“右”列并随着路堤深度的增加而更加显著,临空侧坡体丧失承载特性加剧诱发应力扩散的不对称性。Soil-rock mix filled structure such as dam or embankment is inevitably affected by the complex natural environment,and its vertical bearing mechanical characteristics are the focus of attention in construction.Based on the similarity ratio theory of soil and rock in southwest mountainous area,a well-graded embankment model of soil and rock mixed filling is made.Three equally spaced soil pressure boxes are arranged in the adjacent to the center line of the embankment(“left column”),loading plate center line(“middle column”),and adjacent embankment and open slope(“right column”),making them in the initial environmental state(Model A),rainfall saturated environmental state(Model B),and dry wet cyclic environmental state(Model C)respectively,and model load tests and numerical simulations are carried out by using the hierarchical loading program.The research results indicate that Model A and C have good structural properties,with obvious inflection points in the p~s curve and sudden damage.Model B has no inflection point in the load settlement relationship curve,and under the same load,Model C's settlement is between Model A and B;Under the same layer conditions,the soil pressure at the center of the loading plate is greater than that of adjacent soil.The constraint on the“left”column is greater than that on the“right”column,which leads to asymmetric vertical stress diffusion in the soil rock mixed embankment under different environmental conditions.The soil pressure on the“left”column is greater than that on the“right”column and becomes more significant with the increase of embankment depth.Tshe loss of bearing characteristics on the free side slope intensifies the asymmetry of stress diffusion.

关 键 词：路基工程 路堤模型 环境状态 承载力 应力特征 

分 类 号：U416.1[交通运输工程—道路与铁道工程] U414.1