蠕变作用对土工格栅加筋土界面特性影响的研究
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摘要
为了研究土工格栅的蠕变特性对加筋土界面特性的影响,采用蠕变试验设备及大型直剪试验装置,以两种常用的双向土工格栅为研究对象开展加筋土界面特性试验研究,分析了蠕变作用对土工格栅加筋土的筋土界面工作性能的影响规律。试验结果表明,与纯砂相比,土工格栅加筋后试样内摩擦角变化较小、黏聚力增大,土体的抗剪强度提高;与未蠕变土工格栅加筋砂土相比,蠕变后的土工格栅黏聚力降低,且蠕变加载等级越高,黏聚力下降越多;蠕变加载等级为极限荷载的40%时,土工格栅加筋土的黏聚力下降约30%。在同样的加载等级下,初始抗拉强度较低土工格栅的蠕变变形较初始抗拉强度较高的土工格栅蠕变应变略小。
In order to study the effect of creep behavior of geogrid on the interface characteristics of reinforced soil,the creep test equipment and large direct shear test device were used to carry out the experimental study on the interfacial properties of reinforced soil with two kinds of common biaxial geogrid as the research object,and the effect of creep on the mechanical properties of the geogrid reinforced soil was analyzed. The results of the studyindicated that the internal friction angle of reinforced sand and the pure sand were basically the same; the cohesive force increased,which improved the shear strength of the soil. Compared with reinforced sand soil for uncreep geogrid,the creep geogrid cohesive force produced by creep decreased. The higher the creep loading level,themore the cohesive force decreased.When the loading level of creep test was 40 %,geogrid reinforced soil cohesion decreases about 30 %. Under the same loading level,the initial tensile strength was lower,and the creep deformation of geogrid was smaller than that of the geogrid with higher tensile strength.
In order to study the effect of creep behavior of geogrid on the interface characteristics of reinforced soil,the creep test equipment and large direct shear test device were used to carry out the experimental study on the interfacial properties of reinforced soil with two kinds of common biaxial geogrid as the research object,and the effect of creep on the mechanical properties of the geogrid reinforced soil was analyzed. The results of the studyindicated that the internal friction angle of reinforced sand and the pure sand were basically the same; the cohesive force increased,which improved the shear strength of the soil. Compared with reinforced sand soil for uncreep geogrid,the creep geogrid cohesive force produced by creep decreased. The higher the creep loading level,themore the cohesive force decreased.When the loading level of creep test was 40 %,geogrid reinforced soil cohesion decreases about 30 %. Under the same loading level,the initial tensile strength was lower,and the creep deformation of geogrid was smaller than that of the geogrid with higher tensile strength.
引文
[1]李丽华,王钊,唐建设.时温叠加法确定土工合成材料蠕变折减系数[J].岩土力学,2005(1):113-116.
[2]王钊.土工合成材料的蠕变试验[J].岩土工程学报,1994,16(6):96-102.
[3]邹维列,王钊,林晓玲.土工合成材料的蠕变折减系数[J].岩土力学,2004,25(12):1 361-1 363.
[4]郭军辉,程卫国,张滨.土工格栅低温下蠕变特性试验研究[J].岩土力学,2009,30(10):3009-3012.
[5] BATHURST R J,MIYATA Y. Reliability-based analysis of combined installation damage and creep for the tensile rupture limit state of geogrid reinforcement in Japan[J],Soils and Foundations,2015,55(2):437-446.
[6] BECKER L D B,NUNES A L L S. Influence of soil confinement on the creep behavior of geotextiles[J]. Geotextiles and Geomembranes,2015,43(4):351-358.
[7] COSTA C M L,ZORNBERG J G,BUENO B S,COSTA Y D J. Centrifuge evaluation of the time-dependent behavior of geotextile-reinforced soil walls[J]. Geotextiles and Geomembranes,2016,44(2):188-200.
[8] DELSAUTE B,TORRENTI J M,STAQUET S. Modeling basic creep of concrete since setting time[J]. Cement and Concrete Composites,2017,83:239-250.
[9]王晶仁,葛昕声,白晓红,等.考虑老化作用影响的土工格栅蠕变试验研究[J].特种结构,2017,34(6):25-28.
[10]赵鹤晖.考虑老化作用下土工格栅拉伸、蠕变、筋土界面特性的试验研究[D].太原理工大学,2017.
[11]赵鹤晖,袁慧,刘双英,等.土工格栅蠕变后拉伸性能试验研究[J].中外公路,2017,37(1):215-218.
[12]薛超,袁慧,刘双英,等.双向土工格栅的蠕变与收缩特性研究[J].太原理工大学学报,2015,46(6):697-701.
[13]匡希龙.预应变加筋路堤中加筋材料的变形计算[J].公路工程,2015,40(5):23-26.
[14]张震,朱铎义,薛炳春.侧限荷载和温度对PE-HD土工格栅蠕变特性的影响[J].工程塑料应用,2014,42(6):83-87.
[15]杨广庆,王贺,刘华北,等. HDPE土工格栅加筋土结构的筋材长期强度研究[J].东华大学学报(自然科学版),2014,40(2):167-170.
[16]张鹏,周志刚,杨志峰,等.高密度聚乙烯土工格栅拉伸蠕变特性及模型分析[J].西部交通科技,2016,105(4):1-5.
[2]王钊.土工合成材料的蠕变试验[J].岩土工程学报,1994,16(6):96-102.
[3]邹维列,王钊,林晓玲.土工合成材料的蠕变折减系数[J].岩土力学,2004,25(12):1 361-1 363.
[4]郭军辉,程卫国,张滨.土工格栅低温下蠕变特性试验研究[J].岩土力学,2009,30(10):3009-3012.
[5] BATHURST R J,MIYATA Y. Reliability-based analysis of combined installation damage and creep for the tensile rupture limit state of geogrid reinforcement in Japan[J],Soils and Foundations,2015,55(2):437-446.
[6] BECKER L D B,NUNES A L L S. Influence of soil confinement on the creep behavior of geotextiles[J]. Geotextiles and Geomembranes,2015,43(4):351-358.
[7] COSTA C M L,ZORNBERG J G,BUENO B S,COSTA Y D J. Centrifuge evaluation of the time-dependent behavior of geotextile-reinforced soil walls[J]. Geotextiles and Geomembranes,2016,44(2):188-200.
[8] DELSAUTE B,TORRENTI J M,STAQUET S. Modeling basic creep of concrete since setting time[J]. Cement and Concrete Composites,2017,83:239-250.
[9]王晶仁,葛昕声,白晓红,等.考虑老化作用影响的土工格栅蠕变试验研究[J].特种结构,2017,34(6):25-28.
[10]赵鹤晖.考虑老化作用下土工格栅拉伸、蠕变、筋土界面特性的试验研究[D].太原理工大学,2017.
[11]赵鹤晖,袁慧,刘双英,等.土工格栅蠕变后拉伸性能试验研究[J].中外公路,2017,37(1):215-218.
[12]薛超,袁慧,刘双英,等.双向土工格栅的蠕变与收缩特性研究[J].太原理工大学学报,2015,46(6):697-701.
[13]匡希龙.预应变加筋路堤中加筋材料的变形计算[J].公路工程,2015,40(5):23-26.
[14]张震,朱铎义,薛炳春.侧限荷载和温度对PE-HD土工格栅蠕变特性的影响[J].工程塑料应用,2014,42(6):83-87.
[15]杨广庆,王贺,刘华北,等. HDPE土工格栅加筋土结构的筋材长期强度研究[J].东华大学学报(自然科学版),2014,40(2):167-170.
[16]张鹏,周志刚,杨志峰,等.高密度聚乙烯土工格栅拉伸蠕变特性及模型分析[J].西部交通科技,2016,105(4):1-5.