干湿循环作用下压实黄土强度劣化模型试验研究
|
摘要
为了解干湿循环引起的压实黄土强度劣化规律,开展考虑干密度、干湿循环幅度、干湿循环下限含水量三种影响因素的干湿循环三轴试验,得到不同因素影响下的压实黄土强度劣化曲线。采用双曲线函数对劣化度进行拟合,定量分析干密度、干湿循环幅度、干湿循环下限含水量对压实黄土强度劣化规律的影响,建立综合考虑三种影响因素的"压实黄土干湿循环强度劣化模型(CLDM)",并通过SEM图像分析从微观结构角度对强度劣化进行解释。最终通过基于Python语言的二次开发将CLDM模型应用至有限元软件ABAQUS,实现了干湿循环作用下压实黄土填方边坡稳定分析,验证了CLDM模型在数值模拟中的适用性。研究结论可为压实黄土干湿循环强度劣化的分析以及填方边坡灾害预测提供参考。
In order to fully understand the strength deterioration law of compacted loess caused by wetting-drying cycles,a series of triaxial tests considering the influence of the dry density,the wetting-drying amplitude and the lower bound water content of drying-wetting cycles were carried out,and the strength deterioration curves of compacted loess under different influencing factors were obtained. The effects of the dry density, the wetting-drying amplitude and the lower bound water content on the strength deterioration law were quantitatively analyzed by fitting a hyperbolic function to the deterioration data and as a result,a compacted loess deterioration model(CLDM) was established. Besides,SEM tests were carried out to study the microstructure change caused by wetting-drying cycles. A Python-based secondary development of finite element software was carried out in order to apply CLDM to ABAUQS,by which the stability of a loess fill slope after exposure to drying-wetting cycles was analyzed,and the applicability of the CLDM model was validated. Research results provide a theoretical basis for the analysis of the strength deterioration of compacted loess caused by wetting-drying cycles and for the prediction of fill slope disasters.
In order to fully understand the strength deterioration law of compacted loess caused by wetting-drying cycles,a series of triaxial tests considering the influence of the dry density,the wetting-drying amplitude and the lower bound water content of drying-wetting cycles were carried out,and the strength deterioration curves of compacted loess under different influencing factors were obtained. The effects of the dry density, the wetting-drying amplitude and the lower bound water content on the strength deterioration law were quantitatively analyzed by fitting a hyperbolic function to the deterioration data and as a result,a compacted loess deterioration model(CLDM) was established. Besides,SEM tests were carried out to study the microstructure change caused by wetting-drying cycles. A Python-based secondary development of finite element software was carried out in order to apply CLDM to ABAUQS,by which the stability of a loess fill slope after exposure to drying-wetting cycles was analyzed,and the applicability of the CLDM model was validated. Research results provide a theoretical basis for the analysis of the strength deterioration of compacted loess caused by wetting-drying cycles and for the prediction of fill slope disasters.
引文
[1]PIRES L F,BACCHI O O S,REICHARDT K.Gamma ray computed tomography to evaluate wetting/drying soil structure changes[J].Nuclear Instruments and Methods in Physics Research Section B:Beam Interactions with Materials and Atoms,2005,229(3):443-456.
[2]TANG C S,CUI Y J,SHI B,et al.Desiccation and cracking behaviour of clay layer from slurry state under wetting-drying cycles[J].Geoderma,2011,166(1):111-118.
[3]袁志辉,倪万魁,唐春,等.干湿循环下黄土强度衰减与结构强度试验研究[J].岩土力学,2017,38(7):1 894-1 902.(YUANZhihui,NI Wankui,TANG Chun,et al.Experimental study of structure strength and strength attenuation of loess under wettingdrying cycle[J].Rock and Soil Mechanics,2017,38(7):1 894-1 902.(in Chinese))
[4]袁志辉,倪万魁,唐春,等.干湿循环效应下黄土抗拉强度试验研究[J].岩石力学与工程学报,2017,36(增1):3 670-3 677.(YUAN Zhihui,NI Wankui,TANG Chun,et al.Experimental studies of tensile strength of loess in drying-wetting cycle[J].Chinese Journal of Rock Mechanics and Engineering,2017,36(Supp.1):3 670-3 677.(in Chinese))
[5]王飞,李国玉,穆彦虎,等.干湿循环条件下压实黄土变形特性试验研究[J].岩土力学,2016,37(8):2 306-2 312.(WANG Fei,LI Guoyu,MU Yanhu,et al.Experimental study of deformation characteristics of compacted loess subjected to drying-wetting cycle[J].Rock and Soil Mechanics,2016,37(8):2 306-2 312.(in Chinese))
[6]赵贵刚,黄英,张浚枫,等.干湿循环作用下云南红土裂缝发展研究[J].水土保持学报,2017,31(2):157-165.(ZHAO Guigang,HUANG Ying,ZHANG Junfeng,et al.Investigation on the development of cracks of laterite of Yunnan under wetting-drying cycles[J].Journal of Soil and Water Conservation,2017,31(2):157-165.(in Chinese))
[7]程富阳,黄英,周志伟,等.干湿循环下饱和红土不排水三轴试验研究[J].工程地质学报,2017,25(4):1 017-1 026.(CHENGFuyang,HUANG Ying,ZHOU Zhiwei,et al.Undrained triaxial test of saturated laterite under drying-wetting cycle[J].Journal of Engineering Geology,2017,25(4):1 017-1 026.(in Chinese))
[8]刘文化,杨庆,唐小微,等.干湿循环条件下不同初始干密度土体的力学特性[J].水利学报,2014,45(3):261-268.(LIU Wenhua,YANG Qing,TANG Xiaowei,et al.Mechanical behaviors of soils with different initial dry densities under drying-wetting cycle[J].Journal of Hydraulic Engineering,2014,45(3):261-268.(in Chinese))
[9]涂义亮,刘新荣,钟祖良,等.干湿循环下粉质黏土强度及变形特性试验研究[J].岩土力学,2017,38(12):3 581-3 589.(TU Yiliang,LIU Xinrong,ZHONG Zuliang,et al.Experimental study on strength and deformation characteristics of silty clay during wetting-drying cycles[J].Rock and Soil Mechanics,2017,38(12):3 581-3 589.(in Chinese))
[10]邓华锋,肖瑶,方景成,等.干湿循环作用下岸坡消落带土体抗剪强度劣化规律及其对岸坡稳定性影响研究[J].岩土力学,2017,38(9):2 629-2 638.(DENG Huafeng,XIAO Yao,FANG Jingcheng,et al.Shear strength degradation and slope stability of soils at hydro-fluctuation belt of river bank slope during drying-wetting cycle[J].Rock and Soil Mechanics,2017,38(9):2 629-2 638.(in Chinese))
[11]杨俊,童磊,张国栋,等.干湿循环效应对风化砂改良膨胀土抗剪强度影响研究[J].长江科学院院报,2014,31(4):39-44.(YANG Jun,TONG Lei,ZHANG Guodong,et al.Influence of wet-dry cycles on the shear strength of expansive soil modified by weathered sand[J].Journal of Yangtze River Scientific Research Institute,2014,31(4):39-44.(in Chinese))
[12]曾胜,李振存,韦慧,等.降雨渗流及干湿循环作用下红砂岩顺层边坡稳定性分析[J].岩土力学,2013,34(6):1 536-1 540.(ZENG Sheng,LI Zhencun,WEI Hui,et al.Stability analysis of red sandstone bedding slope under rainfall infiltration and dry-wet cycling[J].Rock and Soil Mechanics,2013,34(6):1 536-1 540.(in Chinese))
[13]杨和平,唐咸远,王兴正,等.有荷干湿循环条件下不同膨胀土抗剪强度基本特性[J].岩土力学,2018,39(7):1-7.(YANG Heping,TANG Xianyuan,WANG Xingzheng,et al.Basic shear strength properties of expansive soils under wet-dry cycles with loading[J].Rock and Soil Mechanics,2018,39(7):1-7.(in Chinese))
[14]陈宾,周乐意,赵延林,等.干湿循环条件下红砂岩软弱夹层微结构与剪切强度的关联性[J].岩土力学,2018,39(5):1-11.(CHENBin,ZHOU Leyi,ZHAO Yanlin,et al.Microstructure and intensity variation of weak sandwich in red sandstone under dry and wet cycles[J].Rock and Soil Mechanics,2018,39(5):1-11.(in Chinese))
[15]吕海波,曾召田,赵艳林,等.胀缩性土强度衰减曲线的函数拟合[J].岩土工程学报,2013,35(增2):157-162.(LV Haibo,ZENGZhaotian,ZHAO Yanlin,et al.Function fitting on strength attenuation curve of swell-shrinking soils[J].Chinese Journal of Geotechnical Engineering,2013,35(Supp.2):157-162.(in Chinese))
[16]NOWAMOOZ H,MASROURI F.Influence of suction cycles on the soil fabric of compacted swelling soil[J].Comptes Rendus Geoscience,2010,342(12):901-910.
[17]SITHARAM T G.Micromechanical modeling of granular materials:effect of confining pressure on mechanical behavior[J].Mechanics of Materials,1999,31(10):653-665.
[18]赵天宇,王锦芳.考虑密度与干湿循环影响的黄土土水特征曲线[J].中南大学学报:自然科学版,2012,43(6):2 445-2 453.(ZHAOTianyu,WANG Jinfang.Soil-water characteristic curve for unsaturated loess soil considering density and wetting-drying cycle effects[J].Journal of Central South University:Science and Technology,2012,43(6):2 445-2 453.(in Chinese))
[19]NOWAMOOZ H,MASROURI F.Influence of suction cycles on the soil fabric of compacted swelling soil[J].Comptes Rendus Geoscience,2010,342(12):901-910.
[20]KHOLGHIFARD M,AHMAD K,ALI N,et al.Collapse/swell potential of residual laterite soil due to wetting and drying-wetting cycles[J].National Academy Science Letters,2014,37(2):147-153.
[21]吕海波,曾召田,赵艳林,等.膨胀土强度干湿循环试验研究[J].岩土力学,2009,30(12):3 797-3 802.(LV Haibo,ZENG Zhaotian,ZHAO Yanlin,et al.Experimental studies of strength of expansive soil in drying and wetting cycle[J].Rock and Soil Mechanics,2009,30(12):3 797-3 802.(in Chinese))
[22]彭小平,陈开圣.干湿循环下红黏土力学特性衰减规律研究[J].工程勘察,2018,(2):1-7.(PENG Xiaoping,CHEN Kaisheng.Study on attenuation law of the mechanical properties of red clay under drying-wetting cycles[J].Geotechnical Investigation and Surveying,2018,(2):1-7.(in Chinese))
[23]中华人民共和国行业标准编写组.SL237-1999土工试验规程[S].北京:中国计划出版社,1999.(The professional Standards Compilation Group of People′s Republic of China.SL237-1999Specification of soil test[S].Beijing:China Planning Press,1999.(in Chinese))
[24]曹玲,王志俭,张振华.降雨-蒸发条件下膨胀土裂隙演化特征试验研究[J].岩石力学与工程学报,2016,35(2):413-421.(CAOLing,WANG Zhijian,ZHANG Zhenhua.Experimental research of cracking process of expansive soil under rainfall infiltration and evaporation[J].Chinese Journal of Rock Mechanics and Engineering,2016,35(2):413-421.(in Chinese))
[25]MEI Y,HU C M,YUAN Y L,et al.Experimental study on deformation and strength property of compacted loess[J].Geomechanics and Engineering,2016,11(1):161-175.
[26]申春妮,方祥位,王和文,等.吸力、含水率和干密度对重塑非饱和土抗剪强度影响研究[J].岩土力学,2009,30(5):1 347-1 351.(SHEN Chunni,FANG Xiangwei,WANG Hewen,et al.Research on effects of suction,water content and dry density on shear strength of remolded unsaturated soils[J].Rock and Soil Mechanics,2009,30(5):1 347-1 351.(in Chinese))
[27]徐丹,唐朝生,冷挺,等.干湿循环对非饱和膨胀土抗剪强度影响的试验研究[J].地学前缘,2018,(1):286-296.(XU Dan,TANG Chaosheng,LENG Ting,et al.Shear strength of unsaturated expansive soil during wetting-drying cycles[J].Earth Science Frontiers,2018,(1):286-296.(in Chinese))
[28]高国瑞.黄土显微结构分类与湿陷性[J].中国科学,1980,(12):1 203-1 208.(GAO Guorui.Microstructure classification and collapsibility of loess[J].Scientia Sinica,1980,(12):1 203-1 208.(in Chinese))
[29]郑少河,金剑亮,姚海林,等.地表蒸发条件下的膨胀土初始开裂分析[J].岩土力学,2006,27(12):2 229-2 233.(ZHENG Shaohe,JIN Jianliang,YAO Hailin,et al.Analysis of initial cracking behavior of expansive soil due to evaporation[J].Rock and Soil Mechanics,2006,27(12):2 229-2 233.(in Chinese))
[2]TANG C S,CUI Y J,SHI B,et al.Desiccation and cracking behaviour of clay layer from slurry state under wetting-drying cycles[J].Geoderma,2011,166(1):111-118.
[3]袁志辉,倪万魁,唐春,等.干湿循环下黄土强度衰减与结构强度试验研究[J].岩土力学,2017,38(7):1 894-1 902.(YUANZhihui,NI Wankui,TANG Chun,et al.Experimental study of structure strength and strength attenuation of loess under wettingdrying cycle[J].Rock and Soil Mechanics,2017,38(7):1 894-1 902.(in Chinese))
[4]袁志辉,倪万魁,唐春,等.干湿循环效应下黄土抗拉强度试验研究[J].岩石力学与工程学报,2017,36(增1):3 670-3 677.(YUAN Zhihui,NI Wankui,TANG Chun,et al.Experimental studies of tensile strength of loess in drying-wetting cycle[J].Chinese Journal of Rock Mechanics and Engineering,2017,36(Supp.1):3 670-3 677.(in Chinese))
[5]王飞,李国玉,穆彦虎,等.干湿循环条件下压实黄土变形特性试验研究[J].岩土力学,2016,37(8):2 306-2 312.(WANG Fei,LI Guoyu,MU Yanhu,et al.Experimental study of deformation characteristics of compacted loess subjected to drying-wetting cycle[J].Rock and Soil Mechanics,2016,37(8):2 306-2 312.(in Chinese))
[6]赵贵刚,黄英,张浚枫,等.干湿循环作用下云南红土裂缝发展研究[J].水土保持学报,2017,31(2):157-165.(ZHAO Guigang,HUANG Ying,ZHANG Junfeng,et al.Investigation on the development of cracks of laterite of Yunnan under wetting-drying cycles[J].Journal of Soil and Water Conservation,2017,31(2):157-165.(in Chinese))
[7]程富阳,黄英,周志伟,等.干湿循环下饱和红土不排水三轴试验研究[J].工程地质学报,2017,25(4):1 017-1 026.(CHENGFuyang,HUANG Ying,ZHOU Zhiwei,et al.Undrained triaxial test of saturated laterite under drying-wetting cycle[J].Journal of Engineering Geology,2017,25(4):1 017-1 026.(in Chinese))
[8]刘文化,杨庆,唐小微,等.干湿循环条件下不同初始干密度土体的力学特性[J].水利学报,2014,45(3):261-268.(LIU Wenhua,YANG Qing,TANG Xiaowei,et al.Mechanical behaviors of soils with different initial dry densities under drying-wetting cycle[J].Journal of Hydraulic Engineering,2014,45(3):261-268.(in Chinese))
[9]涂义亮,刘新荣,钟祖良,等.干湿循环下粉质黏土强度及变形特性试验研究[J].岩土力学,2017,38(12):3 581-3 589.(TU Yiliang,LIU Xinrong,ZHONG Zuliang,et al.Experimental study on strength and deformation characteristics of silty clay during wetting-drying cycles[J].Rock and Soil Mechanics,2017,38(12):3 581-3 589.(in Chinese))
[10]邓华锋,肖瑶,方景成,等.干湿循环作用下岸坡消落带土体抗剪强度劣化规律及其对岸坡稳定性影响研究[J].岩土力学,2017,38(9):2 629-2 638.(DENG Huafeng,XIAO Yao,FANG Jingcheng,et al.Shear strength degradation and slope stability of soils at hydro-fluctuation belt of river bank slope during drying-wetting cycle[J].Rock and Soil Mechanics,2017,38(9):2 629-2 638.(in Chinese))
[11]杨俊,童磊,张国栋,等.干湿循环效应对风化砂改良膨胀土抗剪强度影响研究[J].长江科学院院报,2014,31(4):39-44.(YANG Jun,TONG Lei,ZHANG Guodong,et al.Influence of wet-dry cycles on the shear strength of expansive soil modified by weathered sand[J].Journal of Yangtze River Scientific Research Institute,2014,31(4):39-44.(in Chinese))
[12]曾胜,李振存,韦慧,等.降雨渗流及干湿循环作用下红砂岩顺层边坡稳定性分析[J].岩土力学,2013,34(6):1 536-1 540.(ZENG Sheng,LI Zhencun,WEI Hui,et al.Stability analysis of red sandstone bedding slope under rainfall infiltration and dry-wet cycling[J].Rock and Soil Mechanics,2013,34(6):1 536-1 540.(in Chinese))
[13]杨和平,唐咸远,王兴正,等.有荷干湿循环条件下不同膨胀土抗剪强度基本特性[J].岩土力学,2018,39(7):1-7.(YANG Heping,TANG Xianyuan,WANG Xingzheng,et al.Basic shear strength properties of expansive soils under wet-dry cycles with loading[J].Rock and Soil Mechanics,2018,39(7):1-7.(in Chinese))
[14]陈宾,周乐意,赵延林,等.干湿循环条件下红砂岩软弱夹层微结构与剪切强度的关联性[J].岩土力学,2018,39(5):1-11.(CHENBin,ZHOU Leyi,ZHAO Yanlin,et al.Microstructure and intensity variation of weak sandwich in red sandstone under dry and wet cycles[J].Rock and Soil Mechanics,2018,39(5):1-11.(in Chinese))
[15]吕海波,曾召田,赵艳林,等.胀缩性土强度衰减曲线的函数拟合[J].岩土工程学报,2013,35(增2):157-162.(LV Haibo,ZENGZhaotian,ZHAO Yanlin,et al.Function fitting on strength attenuation curve of swell-shrinking soils[J].Chinese Journal of Geotechnical Engineering,2013,35(Supp.2):157-162.(in Chinese))
[16]NOWAMOOZ H,MASROURI F.Influence of suction cycles on the soil fabric of compacted swelling soil[J].Comptes Rendus Geoscience,2010,342(12):901-910.
[17]SITHARAM T G.Micromechanical modeling of granular materials:effect of confining pressure on mechanical behavior[J].Mechanics of Materials,1999,31(10):653-665.
[18]赵天宇,王锦芳.考虑密度与干湿循环影响的黄土土水特征曲线[J].中南大学学报:自然科学版,2012,43(6):2 445-2 453.(ZHAOTianyu,WANG Jinfang.Soil-water characteristic curve for unsaturated loess soil considering density and wetting-drying cycle effects[J].Journal of Central South University:Science and Technology,2012,43(6):2 445-2 453.(in Chinese))
[19]NOWAMOOZ H,MASROURI F.Influence of suction cycles on the soil fabric of compacted swelling soil[J].Comptes Rendus Geoscience,2010,342(12):901-910.
[20]KHOLGHIFARD M,AHMAD K,ALI N,et al.Collapse/swell potential of residual laterite soil due to wetting and drying-wetting cycles[J].National Academy Science Letters,2014,37(2):147-153.
[21]吕海波,曾召田,赵艳林,等.膨胀土强度干湿循环试验研究[J].岩土力学,2009,30(12):3 797-3 802.(LV Haibo,ZENG Zhaotian,ZHAO Yanlin,et al.Experimental studies of strength of expansive soil in drying and wetting cycle[J].Rock and Soil Mechanics,2009,30(12):3 797-3 802.(in Chinese))
[22]彭小平,陈开圣.干湿循环下红黏土力学特性衰减规律研究[J].工程勘察,2018,(2):1-7.(PENG Xiaoping,CHEN Kaisheng.Study on attenuation law of the mechanical properties of red clay under drying-wetting cycles[J].Geotechnical Investigation and Surveying,2018,(2):1-7.(in Chinese))
[23]中华人民共和国行业标准编写组.SL237-1999土工试验规程[S].北京:中国计划出版社,1999.(The professional Standards Compilation Group of People′s Republic of China.SL237-1999Specification of soil test[S].Beijing:China Planning Press,1999.(in Chinese))
[24]曹玲,王志俭,张振华.降雨-蒸发条件下膨胀土裂隙演化特征试验研究[J].岩石力学与工程学报,2016,35(2):413-421.(CAOLing,WANG Zhijian,ZHANG Zhenhua.Experimental research of cracking process of expansive soil under rainfall infiltration and evaporation[J].Chinese Journal of Rock Mechanics and Engineering,2016,35(2):413-421.(in Chinese))
[25]MEI Y,HU C M,YUAN Y L,et al.Experimental study on deformation and strength property of compacted loess[J].Geomechanics and Engineering,2016,11(1):161-175.
[26]申春妮,方祥位,王和文,等.吸力、含水率和干密度对重塑非饱和土抗剪强度影响研究[J].岩土力学,2009,30(5):1 347-1 351.(SHEN Chunni,FANG Xiangwei,WANG Hewen,et al.Research on effects of suction,water content and dry density on shear strength of remolded unsaturated soils[J].Rock and Soil Mechanics,2009,30(5):1 347-1 351.(in Chinese))
[27]徐丹,唐朝生,冷挺,等.干湿循环对非饱和膨胀土抗剪强度影响的试验研究[J].地学前缘,2018,(1):286-296.(XU Dan,TANG Chaosheng,LENG Ting,et al.Shear strength of unsaturated expansive soil during wetting-drying cycles[J].Earth Science Frontiers,2018,(1):286-296.(in Chinese))
[28]高国瑞.黄土显微结构分类与湿陷性[J].中国科学,1980,(12):1 203-1 208.(GAO Guorui.Microstructure classification and collapsibility of loess[J].Scientia Sinica,1980,(12):1 203-1 208.(in Chinese))
[29]郑少河,金剑亮,姚海林,等.地表蒸发条件下的膨胀土初始开裂分析[J].岩土力学,2006,27(12):2 229-2 233.(ZHENG Shaohe,JIN Jianliang,YAO Hailin,et al.Analysis of initial cracking behavior of expansive soil due to evaporation[J].Rock and Soil Mechanics,2006,27(12):2 229-2 233.(in Chinese))