Influence on the strength of soil-rock mixture made by the rock block orientation features based on numerical experiment
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摘要: 为了探讨土-石混合体的力学强度受块石定向性特征的影响,开发了二维椭圆块石集合体随机模型(2D Elliptic Block Collection Stochastic Model,简称EBCS2D),并在此基础上进行了双轴压缩数值模拟。模拟结果显示土-石混合体的强度受块石定向性特征的影响,该影响规律与含石量显著关联。通过对各向异性屈服面曲线方程和数值模拟结果的拟合分析,验证了该屈服面曲线方程在表达土-石混合体强度方面的适应性。通过引入土-石相互作用单元的概念,阐明了在低、中、高3种含石量下,块石孤立作用和团簇作用交替主导,造成了块石定向性特征对土-石混合体力学强度的不同规律的影响。Abstract: This paper is to explore the influence on the strength of soil-rock mixture made by the rock block orientation features based on numerical experiment.The 2-D Elliptic Block Collection Stochastic Model (EBCS2D) was developed and a series of bia-axial compression numerical tests were conducted.The result indicates that the strength of soil-rock mixture is affected by the rock block orientation features.This effect is highly related to the block proportion.The results of numerical experiments are fitting in an anisotropic yield surface equation, which proves the equation is suitable on the soil-rock mixture, describing the impact of the block proportion and orientation.The soil-rock interactive unit is introduced to explain the mechanism and result.The soil-rock mixture strength changing patterns to the block orientation features are dominated by isolated effect or clustered effect.The dominating effects vary with the block proportion.
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Key words:
- soil-rock mixture /
- stochastic modeling /
- orientation feature /
- block proportion /
- soil-rock interaction
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表 1 土-石混合体结构参数组合
Table 1. Parameters of soil-rock mixture structure
块石定向性特征 块石形状特征 含石量ABP/% θ0/(°) α2 P0 σ2 无定向性 1.5 0.01 40.1829.0623.17 — — 有定向性 0, 15, 30, 45, 60, 75, 90 0 表 2 土-石混合体中块石和土体力学参数
Table 2. Parameters of soil-rock mixture block and soil
名称 密度/(kg·m-3) 弹性模量E/MPa 泊松比μ 黏聚力c/kPa 内摩擦角φ/(°) 块石 2 580 1 040 0.2 500 38 土体 1 820 10 0.3 43 24 表 3 拟合参数结果
Table 3. The results of fitting parameters
含石量φB/% μ λ α 决定系数 40.18 0.786 62 0.997 74 0.245 24 0.999 88 标准差 0.042 21 0.066 38 0.000 89 29.06 0.641 80 0.769 78 0.236 39 0.999 97 标准差 0.014 01 0.013 23 0.000 69 23.17 0.065 14 0.081 56 0.232 17 1.000 00 标准差 0.138 54 0.146 25 0.000 53 -
[1] 徐文杰, 许强.岩土材料细观结构定量化表述方法研究:以土-石混合体为例[J].岩石力学与工程学报, 2012, 31(3):499-506. http://www.cnki.com.cn/Article/CJFDTotal-YSLX201203010.htm [2] 张抒.基于结构性的土-石混合体斜坡变形特征研究[D].武汉: 中国地质大学(武汉), 2015. [3] 舒志乐, 刘新荣, 刘保县, 等.土-石混合体粒度分形特性及其与含石量和强度的关系[J].中南大学学报:自然科学版, 2010, 41(3):1096-1101. http://www.cnki.com.cn/Article/CJFDTotal-ZNGD201003048.htm [4] 张佩, 杜修力, 金浏, 等.块石长轴倾角对土-石混合体宏观力学性能的影响研究[J].工程力学, 2018, 35(9):74-82. http://d.old.wanfangdata.com.cn/Periodical/gclx201809007 [5] Wen B P, Aydin A.Mechanism of a rainfall-induced slide-debris flow:Constraints from microstructure of its slip zone[J].Engineering Geology, 2005, 78(1):69-88. http://www.sciencedirect.com/science/article/pii/S0013795204002388 [6] 乌云飞.秦巴山区土-石混合体滑坡变形破坏机理研究: 以紫阳县滑坡为例[D].西安: 长安大学, 2012. [7] 周剑, 张路青, 戴福初, 等.基于黏结颗粒模型某滑坡土-石混合体直剪试验数值模拟[J].岩石力学与工程学报, 2013, 31(1):2650-2659. http://www.cnki.com.cn/Article/CJFDTotal-YSLX2013S1009.htm [8] 周中.土-石混合体滑坡的流-固耦合特性及其预测预报研究[D].长沙: 中南大学, 2006. [9] 董云, 柴贺军.土石混合料室内大型直剪试验的改进研究[J].岩土工程学报, 2005, 27(11):94-98. http://www.wanfangdata.com.cn/details/detail.do?_type=perio&id=ytgcxb200511019 [10] 郑瑞华, 张建民, 张嘎, 等.积石峡面板堆石坝材料大型三轴试验研究[J].岩土工程学报, 2011, 33(增刊1):184-188. http://www.wanfangdata.com.cn/details/detail.do?_type=perio&id=7507992 [11] 徐文杰, 胡瑞林, 谭儒蛟.三维极限平衡法在原位水平推剪试验中的应用[J].水文地质工程地质, 2006, 33(6):43-47. http://www.wanfangdata.com.cn/details/detail.do?_type=perio&id=swdzgcdz200606011 [12] 魏匡民, 陈生水, 李国英, 等.基于状态参数的筑坝粗粒土本构模型[J].岩土工程学报, 2016, 38(4):654-661. http://www.wanfangdata.com.cn/details/detail.do?_type=perio&id=ytgcxb201604010 [13] Xu W J, Yue Z Q, Hu R L.Study on the meso-structure and meso-mechanical characteristics of the soil-rock mixture using digital image processing based finite element method[J].International Journal of Rock Mechanics & Mining Sciences, 2008, 45(5):749-762. http://www.sciencedirect.com/science/article/pii/S1365160907001438 [14] 徐文杰, 胡瑞林, 岳中崎.土-石混合体随机细观结构生成系统的研发及其细观结构力学数值试验研究[J].岩石力学与工程学报, 2009, 28(8):1652-1665. http://www.wanfangdata.com.cn/details/detail.do?_type=perio&id=yslxygcxb200908017 [15] 徐文杰, 胡瑞林, 岳中琦, 等.土-石混合体细观结构及力学特性数值模拟研究[J].岩石力学与工程学报, 2007, 26(2):300-311. http://www.cnki.com.cn/Article/CJFDTotal-YSLX200702010.htm [16] 徐文杰, 胡瑞林, 岳中琦, 等.基于数字图像分析及大型直剪试验的土-石混合体块石含量与抗剪强度关系研究[J].岩石力学与工程学报, 2008, 27(5):996-1007. http://d.wanfangdata.com.cn/Periodical/yslxygcxb200805016 [17] 周伟, 刘东, 马刚, 等.基于随机散粒体模型的堆石体真三轴数值试验研究[J].岩土工程学报, 2012, 34(4):748-755. http://www.cqvip.com/QK/95758X/20124/41500987.html [18] Barbero M, Bonini M, Borribrunetto M.Numerical modelling of the mechanical behaviour of bimrock[C]//Anon.Proc.11th ISRM Int.Congress.[S.l.]: Taylor & Francis Ltd., 2007: 377-380. [19] 张抒, 唐辉明.基于细观统计规律的土-石混合体随机模型研究[J].人民长江, 2015, 46(16):48-52, 79. http://www.cnki.com.cn/Article/CJFDTotal-RIVE201516012.htm [20] 王菁莪.黄土坡滑坡滑带土的结构特征与水-力相互作用性质研究[D].武汉: 中国地质大学(武汉), 2012. [21] Oda M, Nakayama H.Yield function for soil with anisotropic fabric[J].Journal of Engineering Mechanics, 1989, 115(1):89-104. doi: 10.1061/(ASCE)0733-9399(1989)115:1(89) [22] Curray J R.The analysis of two-dimensional orientation data[J].The Journal of Geology, 1956, 64(2):117-131. doi: 10.1086/626329 [23] 唐朝晖, 孔涛, 柴波.降雨作用碎石土堆积层滑坡变形规律[J].地质科技情报, 2012, 31(6):168-173. http://www.cqvip.com/QK/93477A/20126/44012126.html [24] 郭子正, 殷坤龙, 唐扬, 等.库水位下降及降雨作用下麻柳林滑坡稳定性评价与预测[J].地质科技情报, 2017, 36(4):260-265, 270. http://www.wanfangdata.com.cn/details/detail.do?_type=perio&id=dzkjqb201704035 [25] 熊爽, 曾江波, 姚文敏, 等.降雨干湿循环作用下的渣土边坡稳定性[J].地质科技情报, 2018, 37(5):240-246. http://www.wanfangdata.com.cn/details/detail.do?_type=perio&id=dzkjqb201805033