粉土地基强夯加固效果影响因素数值模拟研究
|
摘要
以绍兴新东线软基加固工程为背景,采用ABAQUS对强夯加固粉土地基进行模拟,结合现场实测数据分析了夯击次数、夯击能、落距和水位对强夯加固效果的影响。结果表明:锤侧土体塑性应变等值线近似于半椭圆形,随夯击次数的增加,塑性区逐渐增大,且其增量以夯锤侧下方为主;不同夯击能下,强夯的有效加固深度与累积夯沉量比值介于4~5;"轻锤高落"产生的锤土接触应力峰值较"重锤低落"大,但衰减速度更快;地下水位越高,浅部土体强夯产生的超静孔隙水压力及其增幅越大;降低水位可显著提升强夯加固深度。
Based on the reinforcement project of soft foundation of Xindongxian Highway in Shaoxing City,ABAQUS was used to simulate the compaction of silt foundation,combining with measured data,the effects of tamping times,tamping energy,drop height and water level on the reinforcement effect of dynamic compaction are analyzed. The results show that the plastic strain contour line of the soil on the side of pounder similar to semi-elliptical shape,and the range of plastic zone increase gradually with the increase of tamping times,its increment mainly distributed on the side lower of the pounder; under different tamping energy,the ratio of effective reinforcement depth to cumulative settlement is between 4 and 5; the peak contact stress generated by a larger height of drop is greater,it attenuates faster than that by a smaller of drop; the groundwater level is higher,the excess pore water pressure and its increment produced by the dynamic compaction of shallow soil are greater; the reinforcement effect can be obviously promoted by reducing the water level.
Based on the reinforcement project of soft foundation of Xindongxian Highway in Shaoxing City,ABAQUS was used to simulate the compaction of silt foundation,combining with measured data,the effects of tamping times,tamping energy,drop height and water level on the reinforcement effect of dynamic compaction are analyzed. The results show that the plastic strain contour line of the soil on the side of pounder similar to semi-elliptical shape,and the range of plastic zone increase gradually with the increase of tamping times,its increment mainly distributed on the side lower of the pounder; under different tamping energy,the ratio of effective reinforcement depth to cumulative settlement is between 4 and 5; the peak contact stress generated by a larger height of drop is greater,it attenuates faster than that by a smaller of drop; the groundwater level is higher,the excess pore water pressure and its increment produced by the dynamic compaction of shallow soil are greater; the reinforcement effect can be obviously promoted by reducing the water level.
引文
[1]地基处理手册编写委员会.地基处理手册[M].北京:中国建筑工业出版社,2008.
[2]牛志荣,杨桂通.强夯作用下土体动力特性研究[J].工程力学,2006,23(3):118-125.Niu Zhirong,Yang Guitong.Dynamic characteristics of soils during and after dynamic consolidation[J].Engineering Mechanics,2006,23(3):118-125.
[3]韩云山,董彦莉,白晓红.夯锤冲击黄土行程试验研究[J].岩石力学与工程学报,2015,34(3):631-638.Han Yunshan,Dong Yanli,Bai Xiaohong.Model test on process of hammer under dynamic compaction of loess[J].Chinese Journal of Rock Mechanics and Engineering,2015,34(3):631-638.
[4]王威,王建华.高能强夯下地基土体的变形特性[J].岩土力学,2015(S1):315-319.Wang Wei,Wang Jianhua.Numerical modeling of ground settlement under high energy dynamic compaction[J].Rock and Soil Mechanics,2015(S1):315-319.
[5]冯世进,胡斌,张旭,等.强夯参数对夯击效果影响的室内模型试验[J].同济大学学报(自然科学版),2012,40(8):1147-1153.Feng Shijin,Hu Bin,Zhang Xu,et al.Model test study on impact parameters influence on tamping effect[J].Journal of Tongji University(Natural Science),2012,40(8):1147-1153.
[6]邢永强.国道主干线改扩建工程软基处理施工与评价[J].中州煤炭,2006(2):13-14.Xing Yongqiang.Construction and evaluation of soft foundation treatment for expansion and extension project of national trunk road[J].Zhongzhou Coal,2006(2):13-14.
[7]蔡袁强,陈超,徐长节.强夯加固回填土地基的三维数值模拟[J].岩土力学,2007,28(6):1108-1112.Cai Yuanqiang,Chen Chao,Xu Changjie.Three-dimensional numerical simulation of dynamic compaction of backfilled soil[J].Rock and Soil Mechanics,2007,28(6):1108-1112.
[8]姚仰平,张北战.基于体应变的强夯加固范围研究[J].岩土力学,2016,37(9):2663-2671.Yao Yangping,Zhang Beizhan.Reinforcement range of dynamic compaction based on volumetric strain[J].Rock and Soil Mechanics,2016,37(9):2663-2671.
[9]Zhao Y.Field Studies of Dynamic Compaction on Marine Deposits[J].Marine Georesources&Geotechnology,2016,34(4):313-320.
[10]Hajialilue-Bonab M,Zare F S.Investigation on tamping spacing in dynamic compaction using model tests[J].Proceedings of the Institution of Civil Engineers Ground Improvement,2015,167(3):219-231.
[11]Li W,Gu Q,Su L,et al.Finite element analysis of dynamic compaction in soft foundation[J].Procedia Engineering,2011(12):224-228.
[12]Gu Q,Lee F H.Ground response to dynamic compaction of dry sand[J].Géotechnique,2002,52(7):481-493.
[13]宋修广,周志东,张崇高,等.强夯联合井点降水加固粉土地基现场试验[J].公路交通科技,2015(3):51-56.Song Xiuguang,Zhou Zhidong,Zhang Chonggao,et al.Field test on silt foundation treatment with dynamic consolidation method combining with well-point dewatering[J].Journal of Highway and Transportation Research and Development,2015(3):51-56.
[14]厉超,张宏博,陈晓光,等.强夯加固粉土地基孔压及变形特性研究[J].公路,2015(10):40-46.Li Chao,Zhang Hongbo,Chen Xiaoguang,et al.Pore pressure and deformation characteristic of silt foundation under dynamic compaction[J].Highway,2015(10):40-46.
[15]张宏博,厉超,吴建清.地下水位对地基强夯加固效果影响现场试验[J].公路,2015(3):14-19.Zhang Hongbo,Li Chao,Wu Jianqing.Field tests of effects of underground water level on dynamic consolidation[J].Highway,2015(3):14-19.
[16]张峰.碎石土的强夯模型试验研究[J].建筑科学,1992,8(3):25-28.Zhang Feng.Model test research on rock filling by dynamic compaction[J].Building Science,1992,8(3):25-28.
[17]赵华新,凌敏.强夯法研究现状分析[J].合肥工业大学学报(自然科学版),2009(10):1606-1611.Zhao Huaxin,Ling Min.Review of current research on dynamic consolidation[J].Journal of Hefei University of Technology(Natural Science),2009(10):1606-1611.
[18]杜文斌.砂土液化分析及抗液化措施[J].中州煤炭,2003(4):36-37.Du Wenbin.Analysis of sand liquefaction and anti liquefaction measures[J].Zhongzhou Coal,2003(4):36-37.
[2]牛志荣,杨桂通.强夯作用下土体动力特性研究[J].工程力学,2006,23(3):118-125.Niu Zhirong,Yang Guitong.Dynamic characteristics of soils during and after dynamic consolidation[J].Engineering Mechanics,2006,23(3):118-125.
[3]韩云山,董彦莉,白晓红.夯锤冲击黄土行程试验研究[J].岩石力学与工程学报,2015,34(3):631-638.Han Yunshan,Dong Yanli,Bai Xiaohong.Model test on process of hammer under dynamic compaction of loess[J].Chinese Journal of Rock Mechanics and Engineering,2015,34(3):631-638.
[4]王威,王建华.高能强夯下地基土体的变形特性[J].岩土力学,2015(S1):315-319.Wang Wei,Wang Jianhua.Numerical modeling of ground settlement under high energy dynamic compaction[J].Rock and Soil Mechanics,2015(S1):315-319.
[5]冯世进,胡斌,张旭,等.强夯参数对夯击效果影响的室内模型试验[J].同济大学学报(自然科学版),2012,40(8):1147-1153.Feng Shijin,Hu Bin,Zhang Xu,et al.Model test study on impact parameters influence on tamping effect[J].Journal of Tongji University(Natural Science),2012,40(8):1147-1153.
[6]邢永强.国道主干线改扩建工程软基处理施工与评价[J].中州煤炭,2006(2):13-14.Xing Yongqiang.Construction and evaluation of soft foundation treatment for expansion and extension project of national trunk road[J].Zhongzhou Coal,2006(2):13-14.
[7]蔡袁强,陈超,徐长节.强夯加固回填土地基的三维数值模拟[J].岩土力学,2007,28(6):1108-1112.Cai Yuanqiang,Chen Chao,Xu Changjie.Three-dimensional numerical simulation of dynamic compaction of backfilled soil[J].Rock and Soil Mechanics,2007,28(6):1108-1112.
[8]姚仰平,张北战.基于体应变的强夯加固范围研究[J].岩土力学,2016,37(9):2663-2671.Yao Yangping,Zhang Beizhan.Reinforcement range of dynamic compaction based on volumetric strain[J].Rock and Soil Mechanics,2016,37(9):2663-2671.
[9]Zhao Y.Field Studies of Dynamic Compaction on Marine Deposits[J].Marine Georesources&Geotechnology,2016,34(4):313-320.
[10]Hajialilue-Bonab M,Zare F S.Investigation on tamping spacing in dynamic compaction using model tests[J].Proceedings of the Institution of Civil Engineers Ground Improvement,2015,167(3):219-231.
[11]Li W,Gu Q,Su L,et al.Finite element analysis of dynamic compaction in soft foundation[J].Procedia Engineering,2011(12):224-228.
[12]Gu Q,Lee F H.Ground response to dynamic compaction of dry sand[J].Géotechnique,2002,52(7):481-493.
[13]宋修广,周志东,张崇高,等.强夯联合井点降水加固粉土地基现场试验[J].公路交通科技,2015(3):51-56.Song Xiuguang,Zhou Zhidong,Zhang Chonggao,et al.Field test on silt foundation treatment with dynamic consolidation method combining with well-point dewatering[J].Journal of Highway and Transportation Research and Development,2015(3):51-56.
[14]厉超,张宏博,陈晓光,等.强夯加固粉土地基孔压及变形特性研究[J].公路,2015(10):40-46.Li Chao,Zhang Hongbo,Chen Xiaoguang,et al.Pore pressure and deformation characteristic of silt foundation under dynamic compaction[J].Highway,2015(10):40-46.
[15]张宏博,厉超,吴建清.地下水位对地基强夯加固效果影响现场试验[J].公路,2015(3):14-19.Zhang Hongbo,Li Chao,Wu Jianqing.Field tests of effects of underground water level on dynamic consolidation[J].Highway,2015(3):14-19.
[16]张峰.碎石土的强夯模型试验研究[J].建筑科学,1992,8(3):25-28.Zhang Feng.Model test research on rock filling by dynamic compaction[J].Building Science,1992,8(3):25-28.
[17]赵华新,凌敏.强夯法研究现状分析[J].合肥工业大学学报(自然科学版),2009(10):1606-1611.Zhao Huaxin,Ling Min.Review of current research on dynamic consolidation[J].Journal of Hefei University of Technology(Natural Science),2009(10):1606-1611.
[18]杜文斌.砂土液化分析及抗液化措施[J].中州煤炭,2003(4):36-37.Du Wenbin.Analysis of sand liquefaction and anti liquefaction measures[J].Zhongzhou Coal,2003(4):36-37.
© 2004-2018 中国地质图书馆版权所有 京ICP备05064691号 京公网安备11010802017129号 地址：北京市海淀区学院路29号 邮编：100083 电话：办公室：(+86 10)66554848；文献借阅、咨询服务、科技查新：66554700 |