|
|
|
| ROCK SLOPE FRACTURE DAMAGE MODEL CONSIDERING THE EFFECT OF UNLOADING AND ITS APPLICATION |
| LIU Lei,JIA Hongbiao,Ma shuzhi |
| (College of Engineering,China University of Geosciences,Wuhan,Hubei 430074,China) |
|
|
|
|
Abstract The macro-crack distributed in the rock mass continuously worsened after excavation,which may resulting the crack connect to each other and form macroscopic fracture in some areas,and could make the slope become unstable. The slope excavation process of each step is equivalent to the process of applying a distributed load in the excavation face and gradually reduced to zero. During the process of equivalent excavating the slope,the crack near the slope free surface within a certain range will be in the state of tension-shear stress. Based on the continuum mechanics,and combining with the damage mechanics and the fracture mechanics,the constitutive model of damage evolution are solved under the tension-shear stress state. The macroscopic bulk modulus are used to reflect the damage degree of rock,and the destruction degree are defined to represent the destroyed characterization in the actual rock mass. Based on the principle above,The calculation of fractured rock unloading damage model is programmed by using the interface of the FLAC3D. The excavation simulation of Guangxi Fengshan limestone building material mine is studied by the new model. The results of the displacement values and the plastic area under two conditions which are using and do not using the new model are calculated and analyzed. The validity of the new model are proved and the real situation in the slope are more accurately reflected. Using the destruction degree to indicate the damage of the rock mass can be more intuitively and accurately determined the rock mass stable state are proved by comparative analyzing the damage degree and the destruction degree after excavating the rock slope.
|
|
|
|
|
|
| [1] LI H B,XIA X,LI J C. Rock damage control in bedrock blasting excavation for a nuclear power plant[J]. International Journal of Rock Mechanics and Mining Sciences,2010,48(2):210–218.
[2] 杨 军,高文学,金乾坤. 岩石动态损伤特性实验及爆破模型[J]. 岩石力学与工程学报,2001,20(3):320–323.(YANG Jun,GAO Wenxue,JIN Qiankun. Experiment on dynamic damage property of rock and a new damage model for rock fragmentation by blasting[J]. Chinese Journal of Rock Mechanics and Engineering,2001,20(3):320–323.(in Chinese))
[3] HAO H,WU C H,ZHOU Y X. Numerical analysis of blast-induced stress waves in a rock mass with anisotropic continuum damage models,part I:equivalent material property approach[J]. Rock Mechanics and Rock Engineering,2002,35(2):79–94.
[4] MA G W,AN X M. Numerical simulation of blasting-induced rock fractures[J]. International Journal of Rock Mechanics and Mining Sciences,2008,45(6):966–975.
[5] 付晓东,盛 谦,张勇慧. 开挖及动荷载作用下边坡响应的DDA方法研究[J]. 岩石力学与工程学报,2012,31(增1):2 612–2 618. (FU Xiaodong,SHENG Qian,ZHANG Yonghui. Research on DDA method for response of slopes under excavation and dynamic load[J]. Chinese Journal of Rock Mechanics and Engineering,2012,31(Supp.1):2 612–2 618.(in Chinese))
[6] 张强勇,朱维申,陈卫忠. 三峡船闸高边坡开挖卸荷弹塑性损伤分析[J]. 水利学报,1998,8:19–22.(ZHANG Qiangyong,ZHU Weishen,CHEN Weizhong. Analysis of elastoplastic damage for high jointed slope of the Three Gorges Project shiplock during unloading due to excavation[J]. Journal of Hydraulic Engineering,1998,8:19–22.(in Chinese))
[7] 胡英国,卢文波,陈 明. 不同开挖方式下岩石高边坡损伤演化过程比较[J]. 岩石力学与工程学报,2013,32(6):1 176–1 184.(HU Yingguo,LU Wenbo,CHEN Ming,et al. Comparison of damage evolution process of high rock slope excavated by different methods[J]. Chinese Journal of Rock Mechanics and Engineering,2013,32(6):1 176–1 184.(in Chinese))
[8] 胡英国,卢文波,金旭浩,等. 岩石高边坡开挖爆破动力损伤的数值仿真[J]. 岩石力学与工程学报,2012,31(11):2 204–2 213.(HU Yingguo,LU Wenbo,JIN Xuhao,et al. Numerical simulation for excavation blasting dynamic damage of rock high slope[J]. Chinese Journal of Rock Mechanics and Engineering,2012,31(11):2 204–2 213.(in Chinese))
[9] 黄 达,金华辉,黄润秋. 拉剪应力状态下岩体裂隙扩展的断裂力学机制及物理模型试验[J]. 岩土力学,2011,32(4):997–1 002. (HUANG Da,JIN Huahui,HUANG Runqiu. Mechanism of fracture mechanics and physical model test of rocks crack expanding under tension-shear stress[J]. Rock and Soil Mechanics,2011,32(4):997–1 002.(in Chinese))
[10] 陈 亮,刘建锋,王春萍,等. 北山深部花岗岩弹塑性损伤模型研究[J]. 岩石力学与工程学报,2013,32(3):289–298.(CHEN Liang,LIU Jianfeng,WANG Chunping,et al. Elastoplastic damage model of Beishan deep granite[J]. Chinese Journal of Rock Mechanics and Engineering,2013,32(3):289–298.(in Chinese).)
[11] 李术才,许新骥,刘征宇,等. 单轴压缩条件下砂岩破坏全过程电阻率与声发射响应特征及损伤演化[J]. 岩石力学与工程学报,2014,33(1):14–23.(LI Shucai,XU Xinji,LIU Zhengyu,et al. electrical resistivity and acoustic emission response characteristics and damage evolution of sandstone during whole process of uniaxial compression[J]. Chinese Journal of Rock Mechanics and Engineering,2014,33(1):14–23.(in Chinese))
[12] 孙 均,凌建明. 三峡船闸高边坡岩体的细观损伤及长期稳定性研究[J]. 岩石力学与工程学报,1997,16(1):1–7.(SUN jun,LING jianming. On me so damage behavior and long-term stability of high slope rock of the three gorges ship locks[J]. Chinese Journal of Rock Mechanics and Engineering,1997,16(1):1–7.(in Chinese))
[13] 黄润秋. 中国西部岩石高坡应力场特征及其卸荷破裂机制[J]. 工程地质学报,2004,12(增l):7–13.(HUANG runqiu. Geo-stress distribution and unloading fracturing mechanism of high rock slopes in western part of China[J]. Journal of Engineering Geology,2004,12(Supp.l):7–13.(in Chinese))
[14] KEMENY J,COOK N G W. Effective Moduli,Non-Linear Deformation and Strength of a cracked elastic solid. Int. J. Rock Mech. Min. Sci. and Geomech. Abstr.1986:23(2).
[15] 中国航空研究院编著. 应力强度因子手册(修订版)[S]. 北京:科学出版社,1996.
[16] 郑少河,朱维申. 裂隙岩体渗流损伤耦合模型的理论分析[J]. 岩石力学与工程学报,2001,20(2):156–159.(ZHENG Shao-he,ZHU Wei-shen. Theory analysizing of the jointed rock fluid and damage coupling model[J]. Chinese Journal of Rock Mechanics and Engineering,2001,20(2):156–159.(in Chinese))
[17] 李树才,朱维申. 复杂应力状态下断续节理岩体断裂损伤机制研究及其应用[J]. 岩石力学与工程学报,1999,18(2):142–146.(Fractured damage mechanism of discontinuous jointed rock mass under the state of complex stress and its application[J]. Chinese Journal of Rock Mechanics and Engineering,1999,18(2):142–146.(in Chinese))
[18] 易顺民,朱珍德著. 裂隙岩体损伤力学导论[M]. 北京:科学出版社,2005.
[19] Asbby M. F. Hallam S. D.. The failure of brittle solids containing small cracks under compressive stress states[J]. Acta. Metall.,1986:34(3).
[20] Jean Lemaitre,Rodrigue Desmorat,Maxime Sauzay. Anisotropic damage law of evolution[J]. Eur. J. Mech. A/Solids 19(2000) 187–208. |
|
|
|