成都平原典型土石混合填土地基的强夯试验  

Dynamic Compaction Test on Typical Soil-rock MixtureFilled Foundation in Chengdu Plain

作　　者：余志松 冉逸涵 肖世国[2,3] 程晓斌 YU Zhisong;RAN Yihan;XIAO Shiguo;CHENG Xiaobin(Chengdu Eighth Construction Engineering of CDCEG,Chengdu 610081,China;Southwest Jiaotong University,Chengdu 610031,China;MOE Key Laboratory of High-speed Railway Engineering,Southwest Jiaotong University,Chengdu 610031,China)

机构地区：[1]成都建工第八建筑工程有限公司,成都610081 [2]西南交通大学,成都610031 [3]西南交通大学高速铁路线路工程教育部重点实验室,成都610031

出　　处：《高速铁路技术》2024年第5期24-29,47,共7页High Speed Railway Technology

基　　金：四川省交通运输科技项目(2020-A-01);成都建工集团有限公司科技项目(TFSD-011)。

摘　　要：为掌握在高能级夯击作用下成都平原地区的土石混合填土地基的力学行为特征,采用现场点夯与满夯试验方法,测试强夯作用过程中地基沉降量和土体动应力,确定夯沉量与夯击次数的关系。结果表明:(1)该土石混合填土地基沉降量的增长速率随夯击次数的增大逐步非线性减小,在4000 kN·m夯击能作用下的最佳夯击次数为10次;(2)地基中动应力随竖向深度或距夯击点径向距离的增加呈非线性减小,动应力沿径向的平均衰减梯度大于沿深度的平均衰减梯度,锤径范围内的径向动应力衰减梯度大于锤径范围外的衰减梯度;(3)土体有效加固深度与夯击能显著相关;(4)等效拟静力法的强夯动应力估算值为实测值的0.48~0.73倍。研究成果可为类似混合填土地基的强夯技术提供参考。To understand the mechanical behavior characteristics of soil-rock mixture filled foundations in the Chengdu Plain under high-energy compaction,field tests including single-point compaction and full-area compaction were conducted.The settlement of the foundation and dynamic stress in the soil during the dynamic compaction process were measured to establish the relationship between the settlement and the number of blows.The test results indicate that:(1)The growth rate of settlement in the soil-rock mixture filled foundation gradually decreases nonlinearly with an increasing number of blows,and the optimal number of blows under a compaction energy of 4000 kN·m is 10 times.(2)The dynamic stress in the foundation decreases nonlinearly with increasing vertical depth or radial distance from the compaction point,with the average attenuation gradient along the radial direction being greater than that along the depth.The attenuation gradient of radial dynamic stress within the hammer diameter is more significant than that outside the hammer diameter.(3)The effective reinforcement depth of the soil is significantly correlated with the compaction energy.(4)The estimated dynamic stress values obtained using the equivalent quasi-static method are 0.48 to 0.73 times the measured values.The research findings provide a reference for dynamic compaction techniques applied to similar mixed-fill foundations.

关 键 词：强夯法 土石混合填土 现场试验 沉降量 动应力 

分 类 号：TU472.3[建筑科学—结构工程]