摘要
为确定高速铁路路基的强夯加固效果及其技术参数,以某高速铁路粉土及粉质黏土路基为工程背景,采用现场试验和数值模拟相结合的方法,研究15和20 m等2种落距时,路基承载力和变形的变化及特征。结果表明:随着夯击次数的增加,路基土单次夯击下沉量逐渐减小并逐渐趋于稳定,各落距后两击下沉量能够满足设计的夯击终止条件;夯击后,表层土体含水率、干密度及比贯入阻力均有明显改善,有效加固区内加固效果明显;夯击后,3个试验测点处的路基承载力特征值均大于150 kPa,能够满足工程设计要求;夯击初期数值计算结果略小于现场试验结果,但随着夯击次数的增加,模拟结果与现场试验结果吻合良好。
In order to determine reinforcement effects and technical parameters of dynamic compaction on roadbed,with silt and silty clay roadbed of a high speed railway as research object,bearing capacity and deformation law and features of reinforced roadbed by dynamic compaction at 15 and 20 m falling distances were studied through site experiment and numerical simulation.The results show that as tamping times increase,compaction settlement for each tamping decreases and gradually stabilizes,and settlements of last two tamping of each falling distance can meet termination condition of engineering design.When dynamic compaction is applied,water content,dry density and specific penetration resistance of surface soil are all significantly improved with obvious reinforcement effect achieved in efficient reinforcement area.And bearing capacity characteristic values of roadbeds in three test points are greater than 150 kPa,which meets designing requirements.In early stage of dynamic compaction,numerical simulation results are slightly smaller than those of field test,but they agree well with each other as tamping times increase.
作者
贾剑青
贾超
赖远明
赵阳阳
王宏图
JIA Jianqing;JIA Chao;LAI Yuanming;ZHAO Yangyang;WANG Hongtu(School of Traffic and Transportation,Lanzhou Jiaotong University,Lanzhou Gansu 730070,China;Northwest Institute of Eco-Environment and Resources,Chinese Academy of Sciences,Lanzhou Gansu 730013,China;China Railway Third Bureau Group Sixth Engineering Co.,Ltd.,Jinzhong Shanxi 030600,China;School of Resources and Safety Engineering,Chongqing University,Chongqing 400044,China)
出处
《中国安全科学学报》
CAS
CSCD
北大核心
2020年第6期50-56,共7页
China Safety Science Journal
基金
国家自然科学基金资助(51104081)
兰州交通大学’百名青年优秀人才培养计划’基金资助(152022)。
关键词
铁路路基
强夯加固
承载力
落距
夯沉量
railway roadbed
dynamic compaction reinforcement
bearing capacity
falling distance
compaction settlement
