刚性与柔性顶部边界下筋土界面特性的细观数值研究
|
摘要
土工格栅拉拔试验被认为是研究土工格栅与土相互作用行为最直接有效的方法。在土工格栅拉拔试验中,常采用刚性或柔性顶部边界条件施加竖向荷载。为了研究刚性与柔性顶部边界条件对拉拔试验结果的影响,基于离散元数值模拟,从细观层面深入分析了刚性与柔性顶部边界条件下土工格栅与土的力学响应。研究结果表明:在拉拔位移较小的情况下,刚性与柔性顶部边界条件对拉拔试验结果几乎没有影响;随着拉拔位移的增大,顶部边界条件对拉拔试验结果的影响逐渐明显,刚性顶部边界条件下的最大拉拔阻力略大于柔性顶部边界条件下的最大拉拔阻力;土工格栅张力与试样内部土颗粒间接触力分布情况、试样内部土颗粒旋转情况以及顶部加载板颗粒的竖向位移分布规律直观地展现了顶部边界条件对拉拔试验结果的影响。本研究结果有望为规范土工格栅拉拔试验方法提供科学依据。
The pullout tests on geogrids have been regarded as the most direct way to investigate the geogrid-soil interaction. In the pullout tests on geogrids, either a rigid or a flexible top boundary is commonly used for applying the vertical loads. In order to investigates the influence of rigid and flexible top boundaries on pullout test results, discrete element modeling is carried out to deeply analyze the mechanical response of geogrids and soils under rigid and flexible top boundary conditions from the mesoscopic scale. The results show that the rigid and flexible top boundaries have almost no effects on the pullout test results when the pullout displacement is small. With the increasing pullout displacement, the influences of the top boundaries on the pullout test results become obvious. The maximum pullout resistance under the rigid top boundary conditions is slightly larger than that under flexible ones. Moreover, the influences of the top boundaries on the pullout test results can be visualized by the tensile force distribution of geogrids, the contact force distribution of soil particles in the specimens, the rotations of soil particles and the vertical displacement distribution of top loading particles. The investigation results in this study may provide scientific references for regulating the pullout test methods for geogrids.
The pullout tests on geogrids have been regarded as the most direct way to investigate the geogrid-soil interaction. In the pullout tests on geogrids, either a rigid or a flexible top boundary is commonly used for applying the vertical loads. In order to investigates the influence of rigid and flexible top boundaries on pullout test results, discrete element modeling is carried out to deeply analyze the mechanical response of geogrids and soils under rigid and flexible top boundary conditions from the mesoscopic scale. The results show that the rigid and flexible top boundaries have almost no effects on the pullout test results when the pullout displacement is small. With the increasing pullout displacement, the influences of the top boundaries on the pullout test results become obvious. The maximum pullout resistance under the rigid top boundary conditions is slightly larger than that under flexible ones. Moreover, the influences of the top boundaries on the pullout test results can be visualized by the tensile force distribution of geogrids, the contact force distribution of soil particles in the specimens, the rotations of soil particles and the vertical displacement distribution of top loading particles. The investigation results in this study may provide scientific references for regulating the pullout test methods for geogrids.
引文
[1]HAN J,THAKUR J K.Sustainable roadway construction using recycled aggregates with geosynthetics[J].Sustainable Cities and Society,2015,14:342-350.
[2]陈福全,赖丰文.抗土洞塌陷的低填方加筋路基荷载传递机制及设计方法[J].岩土工程学报,2018,40(7):1180-1189.(CHEN Fu-quan,LAI Feng-wen.Load transfer mechanisms and design method of low geosyntheticsreinforced embankments subjected to localized sinkholes[J].Chinese Journal of Geotechnical Engineering,2018,40(7):1180-1189.(in Chinese))
[3]介玉新,秦晓艳,金鑫,等.加筋高边坡的稳定分析[J].岩土工程学报,2012,34(4):660-666.(JIE Yu-xin,QINXiao-yan,JIN Xin,et al.Stability of high reinforced soil slopes[J].Chinese Journal of Geotechnical Engineering,2012,34(4):660-666.(in Chinese))
[4]包承纲,汪明远,丁金华.格栅加筋土工作机理的试验研究[J].长江科学院院报,2013,30(1):34-41.(BAOCheng-gang,WANG Ming-yuan,DING Jin-hua.Mechanism of soil reinforced with geogrid[J].Journal of Yangtze River Scientific Research Institute,2013,30(1):34-41.(in Chinese))
[5]MORACI N,RECALCATI P.Factors affecting the pullout behaviour of extruded geogrids embedded in a compacted granular soil[J].Geotextiles and Geomembranes,2006,24(4):220-242.
[6]杨广庆,李广信,张保俭.土工格栅界面摩擦特性试验研究[J].岩土工程学报,2006,28(8):948-952.(YANGGuang-qing,LI Guang-xin,ZHANG Bao-jian.Experimental studies on interface friction characteristics of geogrids[J].Chinese Journal of Geotechnical Engineering,2006,28(8):948-952.(in Chinese))
[7]徐超,廖星樾.土工格栅与砂土相互作用机制的拉拔试验研究[J].岩土力学,2011,32(2):423-428.(XU Chao,LIAO Xing-yue.Researches on interaction mechanism between geogrid and sand by pull-out tests[J].Rock and Soil Mechanics,2011,32(2):423-428.(in Chinese))
[8]肖成志,冯晓静.土工格栅-黏性土界面特性的拉拔试验分析[J].土木建筑与环境工程,2012,34(3):47-51,83.(XIAO Cheng-zhi,FENG Xiao-jing.Pullout-test analysis on properties of interface between geogrid and clay[J].Journal of Civil,Architectural&Environmental Engineering,2012,34(3):47-51,83.(in Chinese))
[9]WANG Z,JACOBS F,ZIEGLER M.Experimental and DEMinvestigation of geogrid-soil interaction under pullout loads[J].Geotextiles and Geomembranes,2016,44(3):230-246.
[10]EZZEIN F M,BATHURST R J.A new approach to evaluate soil-geosynthetic interaction using a novel pullout test apparatus and transparent granular soil[J].Geotextiles and Geomembranes,2014,42(3):246-255.
[11]王家全,周岳富,夏雨,等.新型可视土工拉拔试验仪的研发与应用[J].岩土工程学报,2016,38(4):718-725.(WANG Jia-quan,ZHOU Yue-fu,XIA Yu,et al.Development and application of new visual pullout test apparatus for geosynthetics[J].Chinese Journal of Geotechnical Engineering,2016,38(4):718-725.(in Chinese))
[12]STAHL M,KONIETZKY H,TE KAMP L,et al.Discrete element simulation of geogrid-stabilised soil[J].Acta Geotechnica,2014,9(6):1073-1084.
[13]郑俊杰,周燕君,赖汉江,等.格栅加筋砂土拉拔试验界面特性的离散元模拟[J].华中科技大学学报(自然科学版),2014,42(8):104-108.(ZHENG Jun-jie,ZHOU Yan-jun,LAI Han-jiang,et al.DEM analysis of characteristic of interface between geogrid and sand in pullout test[J].Journal of Huazhong University of Science&Technology(Natural Science Edition),2014,42(8):104-108.(in Chinese))
[14]王家全,周健,吴辉琴,等.加筋土拉拔界面作用的离散元细观模拟[J].哈尔滨工程大学学报,2014,35(7):839-845.(WANG Jia-quan,ZHOU Jian,WU Hui-qin,et al.Discrete element mesoscopic simulation of the reinforced soil pullout test interface effect[J].Journal of Harbin Engineering University,2014,35(7):839-845.(in Chinese))
[15]MIAO C X,ZHENG J J,ZHANG R J,et al.DEM modeling of pullout behavior of geogrid reinforced ballast:The effect of particle shape[J].Computers and Geotechnics,2017,81:249-261.
[16]PALMEIRA E M,MILLIGAN G W E.Scale and other factors affecting the results of pull-out tests of grids buried in sand[J].Géotechnique,1989,39(3):511-542.
[17]HUANG B,BATHURST R J.Evaluation of soil-geogrid pullout models using a statistical approach[J].Geotechnical Testing Journal,2009,32(6):489-504.
[18]ABDI M R,ARJOMAND M A.Pullout tests conducted on clay reinforced with geogrid encapsulated in thin layers of sand[J].Geotextiles and Geomembranes,2011,29(6):588-595.
[19]JACOBS F,ZIEGLER M,VOLLMERT L,et al.Explicit design of geogrids with a nonlinear interface model[C]//Proceedings of 10th International Conference on Geosynthetics.Berlin,2014.
[20]ASTM D6706-01 Standard test method for measuring geosynthetic pullout resistance in soil[S].2013.
[21]JTG E50-2006公路工程土工合成材料试验规程[S].2006.(JTG E50-2006 Test methods of geosynthetics for highway engineering[S].2006.(in Chinese))
[22]SL 235-2012土工合成材料测试规程[S].2012.(SL 235-2012 Specification for test and measurement of geosynthetics[S].2012.(in Chinese))
[23]WANG Z,JACOBS F,ZIEGLER M.Visualization of load transfer behaviour between geogrid and sand using PFC2D[J].Geotextiles and Geomembranes,2014,42(2):83-90.
[24]WANG Z,RUIKEN A,JACOBS F,ZIEGLER M.A new suggestion for determining 2D porosities in DEM studies[J].Geomechanics and Engineering,2014,7(6):665-678.
[2]陈福全,赖丰文.抗土洞塌陷的低填方加筋路基荷载传递机制及设计方法[J].岩土工程学报,2018,40(7):1180-1189.(CHEN Fu-quan,LAI Feng-wen.Load transfer mechanisms and design method of low geosyntheticsreinforced embankments subjected to localized sinkholes[J].Chinese Journal of Geotechnical Engineering,2018,40(7):1180-1189.(in Chinese))
[3]介玉新,秦晓艳,金鑫,等.加筋高边坡的稳定分析[J].岩土工程学报,2012,34(4):660-666.(JIE Yu-xin,QINXiao-yan,JIN Xin,et al.Stability of high reinforced soil slopes[J].Chinese Journal of Geotechnical Engineering,2012,34(4):660-666.(in Chinese))
[4]包承纲,汪明远,丁金华.格栅加筋土工作机理的试验研究[J].长江科学院院报,2013,30(1):34-41.(BAOCheng-gang,WANG Ming-yuan,DING Jin-hua.Mechanism of soil reinforced with geogrid[J].Journal of Yangtze River Scientific Research Institute,2013,30(1):34-41.(in Chinese))
[5]MORACI N,RECALCATI P.Factors affecting the pullout behaviour of extruded geogrids embedded in a compacted granular soil[J].Geotextiles and Geomembranes,2006,24(4):220-242.
[6]杨广庆,李广信,张保俭.土工格栅界面摩擦特性试验研究[J].岩土工程学报,2006,28(8):948-952.(YANGGuang-qing,LI Guang-xin,ZHANG Bao-jian.Experimental studies on interface friction characteristics of geogrids[J].Chinese Journal of Geotechnical Engineering,2006,28(8):948-952.(in Chinese))
[7]徐超,廖星樾.土工格栅与砂土相互作用机制的拉拔试验研究[J].岩土力学,2011,32(2):423-428.(XU Chao,LIAO Xing-yue.Researches on interaction mechanism between geogrid and sand by pull-out tests[J].Rock and Soil Mechanics,2011,32(2):423-428.(in Chinese))
[8]肖成志,冯晓静.土工格栅-黏性土界面特性的拉拔试验分析[J].土木建筑与环境工程,2012,34(3):47-51,83.(XIAO Cheng-zhi,FENG Xiao-jing.Pullout-test analysis on properties of interface between geogrid and clay[J].Journal of Civil,Architectural&Environmental Engineering,2012,34(3):47-51,83.(in Chinese))
[9]WANG Z,JACOBS F,ZIEGLER M.Experimental and DEMinvestigation of geogrid-soil interaction under pullout loads[J].Geotextiles and Geomembranes,2016,44(3):230-246.
[10]EZZEIN F M,BATHURST R J.A new approach to evaluate soil-geosynthetic interaction using a novel pullout test apparatus and transparent granular soil[J].Geotextiles and Geomembranes,2014,42(3):246-255.
[11]王家全,周岳富,夏雨,等.新型可视土工拉拔试验仪的研发与应用[J].岩土工程学报,2016,38(4):718-725.(WANG Jia-quan,ZHOU Yue-fu,XIA Yu,et al.Development and application of new visual pullout test apparatus for geosynthetics[J].Chinese Journal of Geotechnical Engineering,2016,38(4):718-725.(in Chinese))
[12]STAHL M,KONIETZKY H,TE KAMP L,et al.Discrete element simulation of geogrid-stabilised soil[J].Acta Geotechnica,2014,9(6):1073-1084.
[13]郑俊杰,周燕君,赖汉江,等.格栅加筋砂土拉拔试验界面特性的离散元模拟[J].华中科技大学学报(自然科学版),2014,42(8):104-108.(ZHENG Jun-jie,ZHOU Yan-jun,LAI Han-jiang,et al.DEM analysis of characteristic of interface between geogrid and sand in pullout test[J].Journal of Huazhong University of Science&Technology(Natural Science Edition),2014,42(8):104-108.(in Chinese))
[14]王家全,周健,吴辉琴,等.加筋土拉拔界面作用的离散元细观模拟[J].哈尔滨工程大学学报,2014,35(7):839-845.(WANG Jia-quan,ZHOU Jian,WU Hui-qin,et al.Discrete element mesoscopic simulation of the reinforced soil pullout test interface effect[J].Journal of Harbin Engineering University,2014,35(7):839-845.(in Chinese))
[15]MIAO C X,ZHENG J J,ZHANG R J,et al.DEM modeling of pullout behavior of geogrid reinforced ballast:The effect of particle shape[J].Computers and Geotechnics,2017,81:249-261.
[16]PALMEIRA E M,MILLIGAN G W E.Scale and other factors affecting the results of pull-out tests of grids buried in sand[J].Géotechnique,1989,39(3):511-542.
[17]HUANG B,BATHURST R J.Evaluation of soil-geogrid pullout models using a statistical approach[J].Geotechnical Testing Journal,2009,32(6):489-504.
[18]ABDI M R,ARJOMAND M A.Pullout tests conducted on clay reinforced with geogrid encapsulated in thin layers of sand[J].Geotextiles and Geomembranes,2011,29(6):588-595.
[19]JACOBS F,ZIEGLER M,VOLLMERT L,et al.Explicit design of geogrids with a nonlinear interface model[C]//Proceedings of 10th International Conference on Geosynthetics.Berlin,2014.
[20]ASTM D6706-01 Standard test method for measuring geosynthetic pullout resistance in soil[S].2013.
[21]JTG E50-2006公路工程土工合成材料试验规程[S].2006.(JTG E50-2006 Test methods of geosynthetics for highway engineering[S].2006.(in Chinese))
[22]SL 235-2012土工合成材料测试规程[S].2012.(SL 235-2012 Specification for test and measurement of geosynthetics[S].2012.(in Chinese))
[23]WANG Z,JACOBS F,ZIEGLER M.Visualization of load transfer behaviour between geogrid and sand using PFC2D[J].Geotextiles and Geomembranes,2014,42(2):83-90.
[24]WANG Z,RUIKEN A,JACOBS F,ZIEGLER M.A new suggestion for determining 2D porosities in DEM studies[J].Geomechanics and Engineering,2014,7(6):665-678.
© 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 |