Abstract:The dynamic characteristics of the undisturbed loess in Haidong area of Qinghai Province are studied by using the British GDS bidirectional dynamic triaxial test system. The test results show that: when the dynamic strainε<sub>d</sub> is smaller than 1%, the dynamic shear modulus decreases sharply with the increase of the dynamic strain, while it decreases slowly with the increase of the dynamic strain and tends to be stable at the later stage when the dynamic strainε<sub>d</sub> is larger than 1%. The dynamic shear modulus increases with the increase of the consolidation confining pressure, consolidation stress ratio and loading frequency, in addition, the increasing amplitude decreases with the increase of the strain. When the dynamic strainε<sub>d</sub> is smaller than 0.5%, the damping ratio increases rapidly with the increase of the dynamic strain. When the dynamic strainε<sub>d</sub> is larger than 0.5%, the damping ratio increases slowly with the increase of the dynamic strain. When the dynamic strain is small, the consolidation confining pressure, consolidation stress ratio and loading frequency have no clear influence on the damping ratio. With the increase of the dynamic strain, the damping ratio decreases with the increase of the confining pressure and loading frequency, however, it increases with the increase of the consolidation stress ratio.
文少杰, 张吾渝, 曾垂青. 海东地区原状黄土动剪切模量与阻尼比试验研究[J]. 岩土工程学报, 2019, 41(S2): 137-140.
WEN Shao-jie, ZHANG Wu-yu, ZENG Cui-qing. Experimental study on dynamic shear modulus and damping ratio of undisturbed loess in Haidong area. Chinese J. Geot. Eng., 2019, 41(S2): 137-140.
[1] 张吾渝. 黄土工程[M]. 北京: 中国建材工业出版社, 2018. (ZHANG Wu-yu.Loess engineering[M]. Beijing: China Building Materials Press, 2018. (in Chinese)) [2] 李瑞山, 陈龙伟, 袁晓铭. 荷载频率对动模量阻尼比影响的试验研究[J]. 岩土工程学报, 2017, 39(1): 71-80. (LI Rui-shan, CHEN Long-wei, YUAN Xiao-ming, et al.Experimental study on influences of different loading frequencies on dynamic modulus and damping ratio[J]. Chinese Journal of Geotechnical Engineering, 2017, 39(1): 71-80. (in Chinese)) [3] 刘亚明, 王家鼎, 谷天峰. 循环荷载下压实黄土动力特性的试验研究[J]. 水文地质工程地质, 2015, 42(3). (LIU Ya-ming, WANG Jia-ding, et al.Dynamic characteristics of compacted loess under cyclic loads[J]. Hydrogeology & Engineering Geology, 2015, 42(3). (in Chinese)) [4] 骆亚生, 田堪良. 非饱和黄土的动剪模量与阻尼比[J]. 水利学报, 2005, 36(7): 830-834. (LUO Ya-sheng, TIAN Kan-liang. Dynamic shear modulus and damping ratio of unsaturated loess[J]. Journal of Hydraulic Engineering, 2005, 36(7): 830-834. ( in Chinese)) [5] 王军海, 刘亚明. 基于动三轴试验的压实黄土动强度特性研究[J]. 地震工程学报, 2016, 38(3): 439-444. (WANG Jun-hai, LIU Ya-ming.Dynamic strength properties of compacted loessbased on dynamic triaxialtest[J]. China Earthquake Engineering Journal, 2016, 38(3): 439-444. (in Chinese)) [6] 刘保健, 张晓荣, 程海涛. 应变控制下压实黄土的动三轴试验研究[J]. 岩土力学, 2007, 28(6): 1073-1076. (LIU Bao-jian, ZHANG Xiao-rong, CHENG Hai-tao.Study on compacted loess under strain control at dynamic triaxialtest[J]. Rock and Soil Mechanics, 2007, 28(6): 1073-1076. (in Chinese)) [7] KRIPAUPRETI E C.Dynamic properties of residual soil over a wide range of strain[C]// Second Pan-American Conference on Unsaturated Soils. Dallas, 2017: 388-397. [8] DUTTA T T, SARIDE S.Influence of shear strain on the poisson’sratio of clean sands[J]. Geotechnical and Geological Engineering, 2016, 34(5): 1359-1373. [9] 李焱, 骆亚生, 谭东岳. 振动频率对压实黄土动强度特性的影响[J]. 水土保持通报, 2009, 29(4): 130-133. (LI Yan, LUO Ya-sheng, TAN Dong-yue.Effects of vibration frequency on dynamic strength properties of compacted loess[J]. Bulletin of Soil and Water Conservation, 2009, 29(4): 130-133. (in Chinese)) [10] 王志杰, 骆亚生, 王瑞瑞. 不同地区原状黄土动剪切模量与阻尼比试验研究[J]. 岩土工程学报, 2010, 28(9): 1464-1469. (WANG Zhi-jie, LUO Ya-sheng, WANG Rui-rui.Experimental study on dynamic shear modulus and damping ratio of undisturbed loess in different regions[J]. Chinese Journal of Geotechnical Engineering, 2010, 28(9):1464-1469. (in Chinese)) [11] 万战胜, 杨喆, 王家鼎. 列车振动荷载作用下原状黄土动力特性试验[J]. 煤田地质与勘探, 2011, 39(2): 47-51. (WAN Zhan-sheng, YANG Zhe, WANG Jia-ding.Experimental study on dynamic properties of intact loess under train vibrating load[J]. Coal Geology & Exploration, 2011, 39(2): 47-51. (in Chinese)) [12] 骆亚生, 李瑞, 田堪良. 非饱和黄土动力特性试验方法研究[J]. 地下空间与工程学报, 2007(6): 1041-1046. (LUO Ya-sheng, LI Rui, TIAN Kan-liang.Research on method of dynamic characteristics tests for unsaturated loess[J]. Chinese Journal of Underground Space and Engineering, 2007(6): 1041-1046. (in Chinese)) [13] 郭婷婷, 秦梅梅. 土动三轴试验参数选取的理论分析与计算[J]. 工程抗震与加固改造, 2016, 38(2): 144-149. (GUO Ting-ting, QIN Mei-mei.Theoretic analysis of parameters selection of dynamic triaxialtests[J]. Earthquake Resistant Engineering and Retrofitting, 2016, 38(2): 144-149. (in Chinese))