一夯多击方法在改良软土路基施工的应用研究  

Application Research of the One-Compact-Multiple-Impacts Method in Improving Soft Soil Roadbed Construction

作　　者：许海亮 魏亚博 张茂红 XU Hailiang;WEI Yabo;ZHANG Maohong(School of Civil Engineering,North University of Technology,Beijing 100144,China;Beijing Jian Gong Civil Engineering Co.,Ltd.,Beijing 100015,China)

机构地区：[1]北方工业大学土木工程学院,北京100144 [2]北京建工土木工程有限公司,北京100015

出　　处：《北方工业大学学报》2024年第5期57-64,共8页Journal of North China University of Technology

基　　金：国家自然科学基金项目(51774015)。

摘　　要：为解决改良高液限土等软土路基压实困难的问题,本文提出了一种高效低能量强夯方法,即一夯多击方法。通过建立夯锤-路基相互作用数值模型,对比分析了普通强夯与一夯多击在相同条件下的作用效果,结果表明,一夯多击方法在处理改良高液体土等软土路基压实过程中,其地基沉降量、有效夯实系数以及等效塑性应变等指标都有明显提升。主要结论如下:采用一夯多击方法,夯击中心点0 m处的夯击位移比普通单夯夯击位移提升19.54%,其它标识点处的位移变化不大,表明一夯多击可以提高夯击深度;一夯多击方法会出现两次应力峰值,两峰值均小于单夯的应力峰值;一夯多击方法夯坑土体隆起量较单夯夯坑隆起量小,夯坑地表沉降量却较单夯沉降量大,计算得到一夯多击的有效夯实系数为85.58%大于单夯的有效夯实系数80.46%;一夯多击方法夯击产生的最大等效塑性应变较单夯夯击的最大等效塑性应变提高23.76%。This study proposes an efficient and low-energy impact compaction method,namely the“one impact,multiple hits”method,to address the difficulty of compacting soft soils such as high-liquid-limit soils in roadbed improvement.By establishing a numerical model of the interaction between the rammer and the subgrade,a comparative analysis is conducted on the effects of conventional impact compaction and the“one impact,multiple hits”method under the same conditions.The results show that the“one impact,multiple hits”method significantly improves the subgrade settlement,effective compaction coefficient,and equivalent plastic strain in the process of compacting soft soils such as high-liquid-limit soils.The main conclusions are as follows.Using the“one impact,multiple hits”method,the ramming displacement at the center point of the impact at 0 m is increased by 19.54%compared to conventional single impact,while the displacement change at other marking points is not significant,indicating that the“one impact,multiple hits”method can increase the ramming depth.The“one impact,multiple hits”method produces two stress peaks,both of which are smaller than the stress peak of a single impact.The bulging amount of the rammed pit soil in the“one impact,multiple hits”method is smaller than that of a single impact,but the surface settlement of the rammed pit is larger than that of a single impact.The calculated effective compaction coefficient of the“one impact,multiple hits”method is 85.58%,which is greater than the effective compaction coefficient of 80.46%for a single impact.The maximum equivalent plastic strain produced by the“one impact,multiple hits”method is 23.76%higher than that produced by a single impact.

关 键 词：道路工程 一夯多击 高液限土 夯沉量 塑性应变 

分 类 号：U416.1[交通运输工程—道路与铁道工程]