摘要
基于湿陷性黄土地基沉降值过大的问题,以银西铁路甘宁段七标为背景,从工程实际出发,对湿陷性黄土变形机理进行了系统分析,运用柱锤冲扩桩法处理湿陷性地基,以现场柱锤冲扩桩法为基础,配合竖向抗压静载试验,得出如下结论:柱锤冲击成孔过程中,桩位的原土受到挤压,对侧向的土产生挤压作用。锤底土体受到强烈冲击,孔底土体被夯实。并且实验结果表明地基的沉降值随着荷载的增大而增大,且桩体施工水泥土平均压实度均达到0.97。桩间土平均压实度均达到0.93,湿陷系数δ_(s)小于0.015。检测结果满足设计要求,达到了预期效果。该实验得到了柱锤扩冲桩法处理湿陷性黄土地基的基本参数,可为类似工程提供依据。
Based on the problem that the settlement value of collapsible loess foundation is too large,this paper systematically analyzes the deformation mechanism of collapsible loess from the engineering practice with the background of the 7th Bid of Ganning section of Yinchuan-Xi’an Railway.The column hammer punching and expanding pile method is used to treat the collapsible foundation.Based on the field column hammer punching and expanding pile method,combined with the vertical compressive static load test,the following conclusions are drawn:in the process of column hammer impacting into holes,the original soil at the pile position is squeezed,and the lateral soil is squeezed.The bottom soil of hammer is strongly impacted and the bottom soil of hole is compacted.The experimental results show that the settlement value of foundation increases with the increase of load,and the average compaction degree of cement soil in pile construction is 0.97.The average compactness of soil between piles reached 0.93,and the collapsibility coefficient δs was less than 0.015.The test results meet the design requirements and achieve the desired results.In this experiment,the basic parameters of column hammer expansion pile method for collapsible loess foundation treatment are obtained,which can provide a basis for similar projects.
作者
江来云
Jiang Laiyun(China Railway Fifth Bureau Group Mechanization Engineering Co.,Ltd.,Hengyang 421000,China)
出处
《山西建筑》
2021年第23期50-52,共3页
Shanxi Architecture
关键词
湿陷性黄土
柱锤冲扩桩
沉降
静载试验
collapsible loess
column hammer expansion pile
settlement
static load test
