Email Alerts
RSS
Study on dynamic modulus and damping ratio of sand gravel under different loading ratios
-
摘要: 为探究加载比和围压对砂砾料动力特性的影响，通过大型动三轴试验，研究不同加载比和围压作用下砂砾料动模量和阻尼比的变化规律。研究结果表明：（1）随着加载比的增大，动应变显著增大，孔压明显上升，最大阻尼比增大；（2）试验数据更能反映出阻尼比随动剪应变发展的变化规律，综合考虑各动力参数的变化，建议砂砾料动模量和阻尼比试验加载比选择范围为1.5~2.0；（3）采用分段拟合法对动应变小于0.01%和大于0.01%的试验数据进行拟合，直线与试验点的拟合度均大于0.96，分段拟合不同试验条件下砂砾料本构关系更为合理；(4)不同试验条件下动剪切模量比与参考剪应变具有良好的归一性，通过二元线性回归得到砂砾料最大动剪切模量关于围压和加载比的经验公式。该方法可为砂砾料动三轴试验及数据处理提供参考。Abstract: In order to explore the dynamic characteristics of sand gravel under the action of loading ratio, through large-scale dynamic triaxial test, the change law of dynamic modulus and damping ratio of sand gravel under different loading ratio and confining pressure is studied, and the influence of different loading ratio and confining pressure on the dynamic parameters of sand gravel is analyzed. The results show that: (1) With the increase of loading ratio, the dynamic strain increases significantly, the pore pressure increases significantly, and the maximum damping ratio increases; (2) The test data can better reflect the variation law of damping ratio with the development of dynamic shear strain. Considering the changes of various dynamic parameters, it is suggested that the selection range of dynamic modulus and damping ratio test loading ratio of gravel is 1.5~2.0; (3) The test data with dynamic strain less than 0.01% and dynamic strain greater than 0.01% are fitted by the subsection fitting method. The fitting degree between the straight line and the test point is greater than 0.96, and the subsection fitting is more reasonable under different test conditions; (4) Under different test conditions, the dynamic shear modulus ratio and the reference shear strain have good normalization, and the test data are reliable. Through binary linear regression, the empirical formula of the maximum dynamic shear modulus of gravel about confining pressure and loading ratio is obtained. This method can provide a reference for dynamic triaxial test and data processing of gravel materials.
-
Key words:
- sand gravel /
- dynamic modulus /
- damping ratio /
- loading ratio /
- maximum dynamic shear modulus
-
图 4 不同加载比下1/Ed－εd关系
Figure 4. 1/Ed－εd relationship relationship under different loading ratios
图 5 加载比为1.5时的1/Ed-εd关系
Figure 5. 1/Ed－εd relationship under the 1.5 action of loading ratio
图 6 不同加载比下孔压与动应变关系曲线
Figure 6. Relation curve between pore water pressure and dynamic strain under different loading ratios
图 7 相同围压下最大动剪切模量Gdmax与加载比C关系曲线
Figure 7. Relationship curve between maximum dynamic shear modulus Gdmax and loading ratio C under the same confining pressure
图 8 不同加载比下Gd/Gdmax-γr关系
Figure 8. Gd/Gdmax-γr relationship under different loading ratios
图 9 不同加载比下最大阻尼比λdmax关系
Figure 9. Maximum damping ratio under different loading ratios λdmax relation
表 1 不同加载比试验方案
Table 1. Test schemes with different loading ratios
试验材料 围压/kPa Kc 加载比 动应力幅值/kPa 砂砾料 400 1.5 1.0 60 120 180 240 300 360 420 480 540 1 000 150 300 450 600 750 900 1 050 1 200 1 350 1 600 240 480 720 960 1 200 1 440 1 680 1 920 2 160 400 1.5 32 47 71 107 160 240 360 540 / 1 000 79 119 178 267 400 600 900 1 350 / 1 600 126 190 284 427 640 960 1 440 2 160 / 400 2.0 17 34 68 135 270 540 / / / 1 000 42 84 169 338 675 1 350 / / / 1 600 68 135 270 540 1 080 2 160 / / / 400 2.5 6 14 35 86 216 540 / / / 1 000 14 35 86 216 540 1 350 / / / 1 600 22 55 138 346 864 2 160 / / / 
下载: 导出CSV
表 2 不同加载比下双曲线模型参数
Table 2. Hyperbolic model parameters under different loading ratios
加载比 围压/kPa a/10−7 b/10−5 R2 εd<0.01% εd>0.01% εd<0.01% εd>0.01% εd<0.01% εd>0.01% 1.0 400 - 7.09 - 1.04 - 0.984 1 000 - 5.15 - 0.40 - 0.981 1 600 - 4.61 - 0.22 - 0.945 1.5 400 4.81 7.42 2.99 1.24 0.999 0.981 1 000 4.18 5.57 0.95 0.40 0.974 0.978 1 600 3.15 4.27 0.67 0.25 1.000 0.965 2.0 400 4.18 7.40 5.03 1.29 0.999 0.993 1 000 3.85 5.71 1.37 0.40 0.999 0.991 1 600 2.99 4.21 1.12 0.27 1.000 0.977 2.5 400 4.09 7.44 4.10 1.13 0.995 1.000 1 000 2.60 4.91 3.83 0.50 0.967 0.992 1 600 2.07 4.21 2.89 0.27 0.964 0.979
下载: 导出CSV
表 3 不同试验条件下最大动剪切模量Gdmax
Table 3. Maximum dynamic shear modulus Gdmax under different test conditions
加载比 围压/kPa Gdmax/MPa εd<0.01% εd>0.01% 1.0 400 - 530.54 1 000 - 730.23 1 600 - 816.25 1.5 400 782.05 506.19 1 000 899.42 675.15 1 600 1 193.24 880.24 2.0 400 908.76 507.79 1 000 976.04 658.73 1 600 1 256.68 892.82 2.5 400 920.09 505.12 1 000 1 448.05 765.08 1 600 1 812.21 892.78
下载: 导出CSV
表 4 不同加载比下模型参数
Table 4. Model parameters under different loading ratios
加载比 n k1 k2 1.0 0.316 30.33 3 263.47 1.5 0.387 90.22 2 723.05 2.0 0.390 141.43 2 699.59 2.5 0.417 240.70 2 665.72 注：k1、k2、n均为试验常数，均由试验所得。
下载: 导出CSV
-
[1] 陈生水, 凤家骥, 袁辉. 砂砾石面板坝关键技术研究[J]. 岩土工程学报,2004,26(1):16-20 doi: 10.3321/j.issn:1000-4548.2004.01.002 CHEN Shengshui, FENG Jiaji, YUAN Hui. Research on key techniques of facing sandy gravel dam[J]. Chinese Journal of Geotechnical Engineering, 2004, 26(1): 16-20. (in Chinese) doi: 10.3321/j.issn:1000-4548.2004.01.002 [2] 董威信, 孙书伟, 于玉贞, 等. 堆石料动力特性大型三轴试验研究[J]. 岩土力学, 2011, 32(增刊2): 296-301 DONG Weixin, SUN Shuwei, YU Yuzhen, et al. Large scale triaxial shear test on dynamic properties of rockfill materials[J]. Rock and Soil Mechanics, 2011, 32(Suppl 2): 296-301. （in Chinese） [3] 王佳. 粗粒土动弹性模量与阻尼比试验研究[D]. 长沙: 中南大学, 2013 WANG Jia. Experimental study on dynamic elasticity modulus and damping ratio of coarse-grained soils[D]. Changsha: Central South University, 2013. (in Chinese)) [4] 房恩泽. 堆石料的模量阻尼试验研究[J]. 水利与建筑工程学报,2015,13(2):173-176 doi: 10.3969/j.issn.1672-1144.2015.02.036 FANG Enze. Study on dynamic shear modulus damping of rock fill materials of Gushui dam[J]. Journal of Water Resources and Architectural Engineering, 2015, 13(2): 173-176. (in Chinese) doi: 10.3969/j.issn.1672-1144.2015.02.036 [5] 李玫, 王艳丽, 谭凡, 等. 筑坝堆石料的动模量阻尼比试验研究[J]. 长江科学院院报,2019,36(9):86-91 doi: 10.11988/ckyyb.20181137 LI Mei, WANG Yanli, TAN Fan, et al. Experimental study on dynamic modulus and damping ratio of dam rockfill materials[J]. Journal of Yangtze River Scientific Research Institute, 2019, 36(9): 86-91. (in Chinese) doi: 10.11988/ckyyb.20181137 [6] 沈珠江, 徐刚. 堆石料的动力变形特性[J]. 水利水运科学研究,1996(2):143-150 SHEN Zhujiang, XU Gang. Deformation behavior of rock materials under cyclic loading[J]. Journal of Nanjing Hydraulic Research Institute, 1996(2): 143-150. (in Chinese) [7] 孔宪京, 娄树莲, 邹德高, 等. 筑坝堆石料的等效动剪切模量与等效阻尼比[J]. 水利学报,2001,32(8):20-25 doi: 10.3321/j.issn:0559-9350.2001.08.004 KONG Xianjing, LOU Shulian, ZOU Degao, et al. The equivalent dynamic shear modulus and equivalent damping ratio of rockfill material for dam[J]. Journal of Hydraulic Engineering, 2001, 32(8): 20-25. (in Chinese) doi: 10.3321/j.issn:0559-9350.2001.08.004 [8] 谭凡, 张婷, 徐晗. 基于大型动三轴试验的筑坝砂砾石料动模量和阻尼比研究[J]. 长江科学院院报,2020,37(7):130-134 doi: 10.11988/ckyyb.20190439 TAN Fan, ZHANG Ting, XU Han. Dynamic modulus and damping ratio of sandy gravel material based on large-scale dynamic triaxial test[J]. Journal of Yangtze River Scientific Research Institute, 2020, 37(7): 130-134. (in Chinese) doi: 10.11988/ckyyb.20190439 [9] 何建新, 王景, 杨海华. 基于大型三轴试验的筑坝材料动力特性对比分析[J]. 水电能源科学,2021,39(8):107-111 HE Jianxin, WANG Jing, YANG Haihua. Comparative analysis of dynamic characteristics of different dam materials based on large triaxial test[J]. Water Resources and Power, 2021, 39(8): 107-111. (in Chinese) [10] 何建新, 王景, 杨海华. 尼雅水库坝料动力特性研究及三维地震反应分析[J]. 水利水电科技进展,2021,41(5):53-61 HE Jianxin, WANG Jing, YANG Haihua. Dynamic characteristics of dam materials and three-dimensional seismic response analysis of Niya Reservoir[J]. Advances in Science and Technology of Water Resources, 2021, 41(5): 53-61. (in Chinese) [11] 何亮, 景宏彬, 李国英. 加筋堆石料的动力残余变形特性[J]. 水利水运工程学报,2018(4):18-23 doi: 10.16198/j.cnki.1009-640X.2018.04.003 HE Liang, JING Hongbin, LI Guoying. Analysis of dynamic residual deformation characteristics of reinforced rockfill[J]. Hydro-Science and Engineering, 2018(4): 18-23. (in Chinese) doi: 10.16198/j.cnki.1009-640X.2018.04.003 [12] 中华人民共和国住房和城乡建设部. 土工试验方法标准: GB/T 50123—2019[S]. 北京: 中国计划出版社, 2019 Ministry of Housing and Urban-Rural Development of the People’s Republic of China. Standard for geotechnical testing method: GB/T 50123—2019[S]. Beijing: China Planning Press, 2019. （in Chinese） [13] 王景. 加载比对筑坝砂砾料动模量和阻尼比影响试验研究[J]. 吉林水利,2021(12):7-13 doi: 10.3969/j.issn.1009-2846.2021.12.003 WANG Jing. Experimental study on the influence of loading ratio on dynamic modulus and damping ratio of dam gravel[J]. Jilin Water Resources, 2021(12): 7-13. (in Chinese) doi: 10.3969/j.issn.1009-2846.2021.12.003 [14] 何昌荣. 动模量和阻尼的动三轴试验研究[J]. 岩土工程学报,1997,19(2):39-48 doi: 10.3321/j.issn:1000-4548.1997.02.006 HE Changrong. Dynamic triaxial test on modulus and damping[J]. Chinese Journal of Geotechnical Engineering, 1997, 19(2): 39-48. (in Chinese) doi: 10.3321/j.issn:1000-4548.1997.02.006 [15] ATKINSON J H, SALLFORS G. Experimental determination of stress-strain-time characteristics in laboratory and in-situ tests[C]∥SMFE. Proceedings of the 10th European Conference on Soil Mechanics and Foundation Engineering. Rotterdam: A A Balkema, 1991: 915-956. [16] ATKINSON J H, RICHARDSON D, STALLEBRASS S E. Effect of recent stress history on the stiffness of over consolidated soil[J]. Géotechnique, 1990, 40(4): 531-540. [17] BURLAND J B. Ninth Laurits Bjerrum Memorial Lecture: “Small is beautiful”—the stiffness of soils at small strains[J]. Canadian Geotechnical Journal, 1989, 26(4): 499-516. doi: 10.1139/t89-064 -
点击查看大图
计量
- 文章访问数: 7
- HTML全文浏览量: 0
- PDF下载量: 0
- 被引次数: 0
