摘要
以宝兰客运专线某段黄土路基为例,借助Midas GTS/NX有限元计算软件,分析了黄土路基湿陷变形对路基挤密区的影响。结果表明:(1)当未挤密区全部发生湿陷时,挤密区边缘剪应力和沉降变形随距挤密区边缘距离的增大逐渐减小,随着深度的增加,竖向应力逐渐增加且增加的范围越来越广,增量也越来越大,湿陷引起的挤密区沉降变形随距挤密区边缘距离呈非线性减小,且减小的速率随着距离挤密区边缘距离的增大越来越小:(2)同一挤密系数下,沉素土挤密桩沉降量>3∶7灰土挤密桩沉降量>2∶8灰土挤密桩的沉降量;挤密系数为0.93时,2∶8灰土挤密桩在不同深度处的沉降量最小;(3)同一挤密系数下,三种桩型的最终累积沉降量素土挤密桩>2∶8灰土挤密桩>3∶7灰土挤密桩;(4)同一桩型下的累积沉降量挤密系数0.87>挤密系数0.93>挤密系数0.90。
Taking a section of loess subgrade of Baotou Lanzhou passenger dedicated line as an example,the influence of collapsible deformation of loess subgrade on subgrade compaction zone is analyzed with Midas GTS/NX finite element calculation software.The results show that the shear stress and settlement deformation of the edge of the compaction zone decrease with the increase of the distance from the edge of the compaction zone,and the vertical stress increases gradually with the increase of the depth,and the increasing range is wider and the increment is larger and larger.The settlement deformation of the compaction area caused by collapsibility decreases nonlinearly with the distance from the edge of the compaction area,and the rate of reduction decreases with the distance from the edge of the compaction area.The increase of the distance from the edge of the compaction area becomes smaller and smaller.Under the same compaction coefficient,the settlement of plain soil compaction pile is greater than that of 3∶7 lime soil compaction pile,and 2∶8 lime soil compaction pile is the least.Under the same compaction coefficient,the final cumulative settlement of plain soil compaction pile is greater than that of 2∶8 lime soil compaction pile,and 3∶7 lime soil compaction pile is the least.The cumulative settlement of the same pile type from large to small is:compaction coefficient 0.87,compaction coefficient 0.93,compaction coefficient 0.90.
作者
袁博
YUAN Bo(Lanzhou Railway Design Institute Co.,Ltd.,Lanzhou 730030,China)
出处
《粉煤灰综合利用》
CAS
2021年第2期65-69,共5页
Fly Ash Comprehensive Utilization
关键词
黄土路基
湿陷
沉降变形
数值模拟
loess subgrade
collapsibility
settlement deformation
numerical simulatio
