土工格栅加筋橡胶砂强度特性试验研究
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摘要
橡胶砂作为轻质、耗能填料在土木工程中有广泛的应用前景,但其强度往往会随橡胶含量的增大而降低。土工格栅常用于对散体材料的加筋补强,研究土工格栅对橡胶砂强度特性的加筋效应具有重要意义。基于三轴压缩试验,对3种不同格栅布置方式(1、2、3层)下的干燥橡胶砂强度特性展开研究,重点考察加筋层数对不同围压(50、100、200k Pa)下、不同配比(0%、10%、20%、30%、40%)橡胶砂的强度参数,如峰值强度、似黏聚力、内摩擦角的影响规律。结果表明:土工格栅加筋橡胶砂的强度参数,包括峰值强度、似黏聚力、内摩擦角,相对于未加筋橡胶砂均有明显提高,提高幅度随土工格栅加筋层数的增加而增大,随着围压的降低而增大;土工格栅对配比为20%橡胶砂的强度加筋效应最为明显;土工格栅加筋橡胶砂的强度参数恢复系数与加筋密度之间呈良好的线性关系;土工格栅加筋橡胶砂的强度特性可由试验所得的经验恢复函数较好地估计。
Rubber-sand mixture(RSM) has long been recognized as a light weight and energy absorbing material with widely usage in civil engineering. Shear strength of RSM usually decreases with inclusion of rubber particles. As geogrid is usually used to improve the shear strength of granular materials, it is of great interesting to find out how geogrid affect the strength of RSM when RSM is reinforced by geogrid. Triaxial tests were carried out on dry RSMs to study the influence of reinforcing geogrid layers on the strength parameters, such as peak deviatoric stress, pseudo cohesive strength and internal friction angle. Five rubber contents(0%, 10%, 20%, 30% and 40%) and three confining pressures(50 kPa, 100 kPa, 200 kPa) were taken into accounted in tests. Test results indicate that peak deviatoric stress, pseudo cohesive strength and internal friction angle of RSMs reinforced by geogrid are significantly improved comparing to those of RSMs without geogrid. These parameters increase with the increase of the number of geogrid reinforcement layers and with the decrease of confining pressure. The reinforcing effect on strength of RSM by geogrid reaches a peak when the rubber content is 20%. The strength recovery coefficients of geogrid reinforced RSMs exhibit linear relations with the reinforcement density of geogrid, and can be estimated well by the empirical curves of this study.
Rubber-sand mixture(RSM) has long been recognized as a light weight and energy absorbing material with widely usage in civil engineering. Shear strength of RSM usually decreases with inclusion of rubber particles. As geogrid is usually used to improve the shear strength of granular materials, it is of great interesting to find out how geogrid affect the strength of RSM when RSM is reinforced by geogrid. Triaxial tests were carried out on dry RSMs to study the influence of reinforcing geogrid layers on the strength parameters, such as peak deviatoric stress, pseudo cohesive strength and internal friction angle. Five rubber contents(0%, 10%, 20%, 30% and 40%) and three confining pressures(50 kPa, 100 kPa, 200 kPa) were taken into accounted in tests. Test results indicate that peak deviatoric stress, pseudo cohesive strength and internal friction angle of RSMs reinforced by geogrid are significantly improved comparing to those of RSMs without geogrid. These parameters increase with the increase of the number of geogrid reinforcement layers and with the decrease of confining pressure. The reinforcing effect on strength of RSM by geogrid reaches a peak when the rubber content is 20%. The strength recovery coefficients of geogrid reinforced RSMs exhibit linear relations with the reinforcement density of geogrid, and can be estimated well by the empirical curves of this study.
引文
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[2]HAN J.Principles and practice of ground improvement[M].London:John Wiley&Sons,2015.
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[4]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.YANG Guang-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.
[5]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.
[6]周小凤,张孟喜,邱成春,等.不同形式土工格栅加筋砂的强度特性[J].上海交通大学学报,2013,47(9):1377-1381.ZHOU Xiao-feng,ZHANG Meng-xi,QIU Cheng-chun,et al.Strength of sand reinforced with different forms of geogrid[J].Journal of Shanghai Jiao Tong University,2013,47(9):1377-1381.
[7]胡幼常,申俊敏,赵建斌,等.土工格栅加筋掺砂黄土工程性质试验研究[J].岩土力学,2013,34(增刊2):74-80.HU You-chang,SHEN Jun-min,ZHAO Jian-bin,et al.Experimental study of engineering properties of geogrid-reinforced loess mixed with sand[J].Rock and Soil Mechanics,2013,34(Supp.2):74-80.
[8]王协群,郭敏,胡波.土工格栅加筋膨胀土的三轴试验研究[J].岩土力学,2011,32(6):1649-1653.WANG Xie-qun,GUO Min,HU Bo.Triaxial testing study of expansive soil reinforced with geogrid[J].Rock and Soil Mechanics,2011,32(6):1649-1653.
[9]LEE J,SALGADO R,BERNAL A,et al.Shredded tires and rubber-sand as lightweight backfill[J].Journal of Geotechnical and Geoenvironmental Engineering,ASCE,1999,125(2):132-141.
[10]XIAO M,BOWEN J,GRAHAM M,et al.Comparison of seismic responses of geosynthetically reinforced walls with tire-derived aggregates and granular backfills[J].Journal of Materials in Civil Engineering,ASCE,2012,24(11):1368-1377.
[11]PATIL U,VALDES J R,EVANS T M.Swell mitigation with granulated tire rubber[J].Journal of Materials in Civil Engineering,2011,23(5):721-727.
[12]SOLTANI-JIGHEH H,ASADZADEH M,MAREFAT V.Effects of tire chips on shrinkage and cracking characteristics of cohesive soils[J].Turkish Journal of Engineering and Environmental Sciences,2013,37:259-271.
[13]CHRIST M,PARK J,HONG S.Laboratory observation of the response of a buried pipeline to freezing rubber-sand backfill[J].Journal of Materials in Civil Engineering,2010,22(9):943-950.
[14]MEHRJARDI G T,TAFRESHI S N M,DAWSON A R.Numerical analysis on buried pipes protected by combination of geocell reinforcement and rubber-soil mixture[J].International Journal of Civil Engineering,Transaction B:Geotechnical Engineering,2015,13(2):90-104.
[15]TSANG H H.Seismic isolation by rubber-soil mixtures for developing countries[J].Earthquake Engineering and Structural Dynamics,2007,37(7):283-303.
[16]TSANG H H,LO S H,XU X,et al.Seismic isolation for low-to-medium-rise buildings using granulated rubbersoil mixtures:Numerical study[J].Earthquake Engneering and Structural Dynamics,2012,41(14):2009-2024.
[17]XIONG W,LI Y Z.Seismic isolation using granulated tire-soil mixtures for less-developed regions:Experimental validation[J].Earthquake Engineering and Structure Dynamics,2013,42(14):2187-2193.
[18]PITILAKIS K,KARAPETROU S,TSAGDI K.Numerical investigation of the seismic response of RCbuildings on soil replaced with rubber-sand mixtures[J].Soil Dynamics and Earthquake Engineering,2015,79:237-252.
[19]BRUNET S,DE LALLERA J C,KAUSEL E.Non-linear modeling of seismic isolation systems made of recycled tire-rubber[J].Soil Dynamics and Earthquake Engineering,2016,(85):134-145.
[20]刘方成,任东滨,刘娜,等.土工格室加筋橡胶砂垫层隔震效果数值分析[J].土木工程学报,2015,47(增刊2):1-7.LIU Fang-cheng,REN Dong-bin,LIU Na,et al.Numerical simulation on the isolation effect of geocell reinforced rubber-sand mixture cushion as earthquake base isolator[J].China Civil Engineering Journal,2015,47(Supp.2):1-7.
[21]刘方成,张永富,周亚栋.土工格室加筋橡胶砂垫层隔震试验研究[J].建筑结构学报,2016,37(增刊1):93-100.LIU Fang-cheng,ZHANG Yong-fu,ZHOU Ya-dong.Experimental study on isolating performance of geo-cell reinforced rubber-sand mixture cushion[J].Journal of Building Structures,2016,37(Supp.1):93-100.
[22]吴孟桃,刘方成,陈巨龙,等.含水率对大应变下橡胶砂动剪模量和阻尼比的影响[J].岩土力学,2018,39(3):803-814.WU Meng-tao,LIU Fang-cheng,CHEN Ju-long,et al.Influence of water content on dynamic shear modulus and damping ratio of rubber-sand mixture under large strains[J].Rock and Soil Mechanics,2018,39(3):803-814.
[23]LIU H S,MEAD J L,STACER R G.Environmental effects of recycled rubber in light-fill applications[J].Rubber Chemistry and Technology,2000,73(3):551-564.
[24]FINNEY B,CHANDLER Z H,BRUCE J L,et al.Properties of tire-derived aggregate for civil engineering applications[R].Sacramento,CA:California Department of Resources Recycling and Recovery,Humbolt State University,2013.
[25]ZORNBERG J G,CABRAL A R,VIRATJANDR C.Behaviour of tire shred sand mixtures[J].Canadian Geotechnical Journal,2004,41(2):227-241.
[26]辛凌,刘汉龙,沈扬,等.废弃轮胎橡胶颗粒轻质混合土强度特性试验研究[J].岩土工程学报,2010,32(3):428-433.XIN Ling,LIU Han-long,SHEN Yang,et al.Consolidated undrained triaxial compression tests on lightweight soil mixed with rubber chips of scrap tires[J].Chinese Journal of Geotechnical Engineering,2010,32(3):428-433.
[27]CABALAR A F.Direct shear tests on waste tires-sand mixtures[J].Geotechnical and Geological Engineering,2011,29(4):411-418.
[28]VINOD J S,SHEIKH M N,MASTELLO D,et al.The direct shear strength of sand tyre shred mixtures[C]//Proceedings of the International Conference on Geotechnical Engineering.Sri Lanka:Sri Lankan Geotechnical Society,2015:193-196.
[29]中华人民共和国水利部.GB/T50123―1999土工试验方法标准[S].北京:中国计划出版社,1999.Ministry of Water Resources of the People's Republic of China.GB/T50123―1999 Standards for Geotechnical Test Methods[S].Beijing:China Planning Press,1999.
[30]AHMED I.Laboratory study on properties of rubber soils[R].West Lafayette:Purdue University,1993.
[31]VERDUGO R,ISHIHARA K.The steady state of sandy soils[J].Soils and Foundations,1996,36(2):81-91.
[32]CHANEY R C,DEMARS K R,FENG Zheng-yi,et al.Dynamic properties of granulated rubber/sand mixtures[J].Geotechnical Testing Journal,2000,23(3):338-344.
[33]EL-SHERBINY R,YOUSSEF A,LOTFY H.Triaxial testing on saturated mixtures of sand and granulated rubber[C]//Proceedings of the 2013 Geo-Congress,Stability and Performance of Slopes and Embankments III.San Diego,CA:ASCE,2013:82-91.
[34]张永富.土工格室加筋橡胶砂隔震垫层动力响应与物性参数反演研究[D].株洲:湖南工业大学,2015.ZHANG Yong-fu.Research on dynamic response and physical character parameter inversion of isolation cushion constructed by geocell reinforced rubber-sand mixture[D].Zhuzhou:Hunan University of Technology,2015.
[35]邓安,冯金荣.砂-轮胎橡胶颗粒轻质土工填料试验研究[J].建筑材料学报,2010,13(1):116-120.DENG An,FENG Jin-rong.Experimental study on sand-shredded tire lightweight fills[J].Journal of Building Materials,2010,13(1):116-120.
[36]保华富,周亦唐,赵川,等.聚合物土工格栅加筋碎石土试验研究[J].岩土工程学报,1999,21(2):217-221.BAO Hua-fu,ZHOU Yi-tang,ZHAO Chuan,et al.Study on georid reinforced stone[J].Chinese Journal of Geotechnical Engineering,1999,21(2):217-221.
[2]HAN J.Principles and practice of ground improvement[M].London:John Wiley&Sons,2015.
[3]彭芳乐,小竹望,龙冈文夫.土工格栅加筋砂土的变形与破坏机制解析[J].岩土力学,2004,25(6):843-849.PENG Fang-le,NOZOMU Kotake,FUMIO Tatsuoke.Numerical analysis of deformation and failure mechanism of geogrid-reinforeed sand[J].Rock and Soil Mechanics,2004,25(6):843-849.
[4]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.YANG Guang-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.
[5]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.
[6]周小凤,张孟喜,邱成春,等.不同形式土工格栅加筋砂的强度特性[J].上海交通大学学报,2013,47(9):1377-1381.ZHOU Xiao-feng,ZHANG Meng-xi,QIU Cheng-chun,et al.Strength of sand reinforced with different forms of geogrid[J].Journal of Shanghai Jiao Tong University,2013,47(9):1377-1381.
[7]胡幼常,申俊敏,赵建斌,等.土工格栅加筋掺砂黄土工程性质试验研究[J].岩土力学,2013,34(增刊2):74-80.HU You-chang,SHEN Jun-min,ZHAO Jian-bin,et al.Experimental study of engineering properties of geogrid-reinforced loess mixed with sand[J].Rock and Soil Mechanics,2013,34(Supp.2):74-80.
[8]王协群,郭敏,胡波.土工格栅加筋膨胀土的三轴试验研究[J].岩土力学,2011,32(6):1649-1653.WANG Xie-qun,GUO Min,HU Bo.Triaxial testing study of expansive soil reinforced with geogrid[J].Rock and Soil Mechanics,2011,32(6):1649-1653.
[9]LEE J,SALGADO R,BERNAL A,et al.Shredded tires and rubber-sand as lightweight backfill[J].Journal of Geotechnical and Geoenvironmental Engineering,ASCE,1999,125(2):132-141.
[10]XIAO M,BOWEN J,GRAHAM M,et al.Comparison of seismic responses of geosynthetically reinforced walls with tire-derived aggregates and granular backfills[J].Journal of Materials in Civil Engineering,ASCE,2012,24(11):1368-1377.
[11]PATIL U,VALDES J R,EVANS T M.Swell mitigation with granulated tire rubber[J].Journal of Materials in Civil Engineering,2011,23(5):721-727.
[12]SOLTANI-JIGHEH H,ASADZADEH M,MAREFAT V.Effects of tire chips on shrinkage and cracking characteristics of cohesive soils[J].Turkish Journal of Engineering and Environmental Sciences,2013,37:259-271.
[13]CHRIST M,PARK J,HONG S.Laboratory observation of the response of a buried pipeline to freezing rubber-sand backfill[J].Journal of Materials in Civil Engineering,2010,22(9):943-950.
[14]MEHRJARDI G T,TAFRESHI S N M,DAWSON A R.Numerical analysis on buried pipes protected by combination of geocell reinforcement and rubber-soil mixture[J].International Journal of Civil Engineering,Transaction B:Geotechnical Engineering,2015,13(2):90-104.
[15]TSANG H H.Seismic isolation by rubber-soil mixtures for developing countries[J].Earthquake Engineering and Structural Dynamics,2007,37(7):283-303.
[16]TSANG H H,LO S H,XU X,et al.Seismic isolation for low-to-medium-rise buildings using granulated rubbersoil mixtures:Numerical study[J].Earthquake Engneering and Structural Dynamics,2012,41(14):2009-2024.
[17]XIONG W,LI Y Z.Seismic isolation using granulated tire-soil mixtures for less-developed regions:Experimental validation[J].Earthquake Engineering and Structure Dynamics,2013,42(14):2187-2193.
[18]PITILAKIS K,KARAPETROU S,TSAGDI K.Numerical investigation of the seismic response of RCbuildings on soil replaced with rubber-sand mixtures[J].Soil Dynamics and Earthquake Engineering,2015,79:237-252.
[19]BRUNET S,DE LALLERA J C,KAUSEL E.Non-linear modeling of seismic isolation systems made of recycled tire-rubber[J].Soil Dynamics and Earthquake Engineering,2016,(85):134-145.
[20]刘方成,任东滨,刘娜,等.土工格室加筋橡胶砂垫层隔震效果数值分析[J].土木工程学报,2015,47(增刊2):1-7.LIU Fang-cheng,REN Dong-bin,LIU Na,et al.Numerical simulation on the isolation effect of geocell reinforced rubber-sand mixture cushion as earthquake base isolator[J].China Civil Engineering Journal,2015,47(Supp.2):1-7.
[21]刘方成,张永富,周亚栋.土工格室加筋橡胶砂垫层隔震试验研究[J].建筑结构学报,2016,37(增刊1):93-100.LIU Fang-cheng,ZHANG Yong-fu,ZHOU Ya-dong.Experimental study on isolating performance of geo-cell reinforced rubber-sand mixture cushion[J].Journal of Building Structures,2016,37(Supp.1):93-100.
[22]吴孟桃,刘方成,陈巨龙,等.含水率对大应变下橡胶砂动剪模量和阻尼比的影响[J].岩土力学,2018,39(3):803-814.WU Meng-tao,LIU Fang-cheng,CHEN Ju-long,et al.Influence of water content on dynamic shear modulus and damping ratio of rubber-sand mixture under large strains[J].Rock and Soil Mechanics,2018,39(3):803-814.
[23]LIU H S,MEAD J L,STACER R G.Environmental effects of recycled rubber in light-fill applications[J].Rubber Chemistry and Technology,2000,73(3):551-564.
[24]FINNEY B,CHANDLER Z H,BRUCE J L,et al.Properties of tire-derived aggregate for civil engineering applications[R].Sacramento,CA:California Department of Resources Recycling and Recovery,Humbolt State University,2013.
[25]ZORNBERG J G,CABRAL A R,VIRATJANDR C.Behaviour of tire shred sand mixtures[J].Canadian Geotechnical Journal,2004,41(2):227-241.
[26]辛凌,刘汉龙,沈扬,等.废弃轮胎橡胶颗粒轻质混合土强度特性试验研究[J].岩土工程学报,2010,32(3):428-433.XIN Ling,LIU Han-long,SHEN Yang,et al.Consolidated undrained triaxial compression tests on lightweight soil mixed with rubber chips of scrap tires[J].Chinese Journal of Geotechnical Engineering,2010,32(3):428-433.
[27]CABALAR A F.Direct shear tests on waste tires-sand mixtures[J].Geotechnical and Geological Engineering,2011,29(4):411-418.
[28]VINOD J S,SHEIKH M N,MASTELLO D,et al.The direct shear strength of sand tyre shred mixtures[C]//Proceedings of the International Conference on Geotechnical Engineering.Sri Lanka:Sri Lankan Geotechnical Society,2015:193-196.
[29]中华人民共和国水利部.GB/T50123―1999土工试验方法标准[S].北京:中国计划出版社,1999.Ministry of Water Resources of the People's Republic of China.GB/T50123―1999 Standards for Geotechnical Test Methods[S].Beijing:China Planning Press,1999.
[30]AHMED I.Laboratory study on properties of rubber soils[R].West Lafayette:Purdue University,1993.
[31]VERDUGO R,ISHIHARA K.The steady state of sandy soils[J].Soils and Foundations,1996,36(2):81-91.
[32]CHANEY R C,DEMARS K R,FENG Zheng-yi,et al.Dynamic properties of granulated rubber/sand mixtures[J].Geotechnical Testing Journal,2000,23(3):338-344.
[33]EL-SHERBINY R,YOUSSEF A,LOTFY H.Triaxial testing on saturated mixtures of sand and granulated rubber[C]//Proceedings of the 2013 Geo-Congress,Stability and Performance of Slopes and Embankments III.San Diego,CA:ASCE,2013:82-91.
[34]张永富.土工格室加筋橡胶砂隔震垫层动力响应与物性参数反演研究[D].株洲:湖南工业大学,2015.ZHANG Yong-fu.Research on dynamic response and physical character parameter inversion of isolation cushion constructed by geocell reinforced rubber-sand mixture[D].Zhuzhou:Hunan University of Technology,2015.
[35]邓安,冯金荣.砂-轮胎橡胶颗粒轻质土工填料试验研究[J].建筑材料学报,2010,13(1):116-120.DENG An,FENG Jin-rong.Experimental study on sand-shredded tire lightweight fills[J].Journal of Building Materials,2010,13(1):116-120.
[36]保华富,周亦唐,赵川,等.聚合物土工格栅加筋碎石土试验研究[J].岩土工程学报,1999,21(2):217-221.BAO Hua-fu,ZHOU Yi-tang,ZHAO Chuan,et al.Study on georid reinforced stone[J].Chinese Journal of Geotechnical Engineering,1999,21(2):217-221.