全部 标题 作者
关键词 摘要

OALib Journal期刊
ISSN: 2333-9721
费用:99美元

查看量下载量

相关文章

更多...
力学学报  2015 

基于单元破裂的岩石裂纹扩展模拟方法

DOI: 10.6052/0459-1879-14-239, PP. 105-118

Keywords: 连续—非连续,单元破裂,裂纹扩展,岩石破坏

Full-Text   Cite this paper   Add to My Lib

Abstract:

传统离散元方法在处理破裂问题时,采用界面上的准则进行判断,裂纹只能沿着单元边界扩展.当物理问题存在宏观或微观裂隙时,在界面上应用准则具有其合理性;而裂纹沿着单元边界扩展,使得裂纹路径受网格影响较大,扩展方向受到限制.针对上述情况,可以基于单元破裂的方式,构建连续-非连续单元法,并应用于岩石裂纹扩展问题的模拟.该方法在连续计算时,将单元离散为具有物理意义的弹簧系统,在局部坐标系下由弹簧特征长度、面积求解单元变形和应力,通过更新局部坐标系和弹簧特征量,可进一步计算块体大位移、大转动,连续问题计算结果与有限元一致,同时提高了计算效率.在此基础上,引入最大拉应力与莫尔—库伦的复合准则,判断单元破裂状态和破裂方向,并采用局部块体切割的方式,在单元内形成初始裂纹.裂纹两侧相应增加新的计算节点,同时引入内聚力模型描述裂纹两侧的法向、切向作用与张开度及滑移变形之间的关系.按此方式,裂纹尖端处的扩展路径可穿过单元内部和单元边界,在扩展方向的选取上更为准确.最后,通过三点弯曲梁、单切口平板拉伸、双切口试样等典型数值试验,模拟裂纹在拉伸、压剪等各种应力状态下的扩展问题,并对岩石单轴压缩试验的破坏过程进行模拟,分析裂纹形成与应力—应变曲线各阶段之间的对应关系.结果表明连续—非连续单元法通过单元内部破裂的方式,可以显示模拟裂纹萌生、扩展、贯通直至形成宏观裂缝的过程.

References

[1]  张楚汉. 论岩石、混凝土离散-接触-断裂分析. 岩石力学与工程学报, 2008, 27(2): 217-235 (Zhang Chuhan. Discrete-contact-fracture analysis of rock and concrete. Chinese Journal of Rock Mechanics and Engineering, 2008, 27(2): 217-235 (in Chinese))
[2]  Swenson DV, Ingraffea AR. Modeling mixed-mode dynamic crack propagation using finite elements: Theory and applications. Computational Mechanics, 1988, 3: 381-397
[3]  Belytschko T, Black T. Elastic crack growth in finite elements with minimal remeshing. International Journal for Numerical Methods in Engineering, 1999, 45(5): 601-620
[4]  Ke TC. Simulated testing of two dimensional heterogeneous and discontinuous rock masses using discontinuous deformation analysis. [PhD Thesis]. Berkeley: University of California, 1993
[5]  Shi GH. Manifold method. In: Salami MR and Banks D eds. Proceedings of the First International Forum on Discontinuous Deformation Analysis (DDA) and Simulation of Discontinuous Media. Berkeley, California, 1996. 52-204
[6]  Shi GH. Numerical manifold method. In: Li JC, Wang CY, Sheng J eds. Proceedings of the First International Conference on Analysis of Discontinuous Deformation (ICADD-1). Chungli, Taiwan, China, 1995. 187-222
[7]  刘丰, 郑宏, 李春光. 基于NMM的EFG方法及其裂纹扩展模拟. 力学学报, 2014, 46(4): 582-590 (Liu Feng, Zheng Hong, Li Chunguang. The NMM-based EFG method and simulation of crack propagation. Chinese Journal of Theoretical and Applied Mechanics, 2014, 46(4): 582-590 (in Chinese))
[8]  杨永涛, 徐栋栋, 郑宏. 动载下裂纹应力强度因子计算的数值流形元法. 力学学报, 2014, 46(5): 730-738 (Yang Yongtao, Xu Dongdong, Zheng Hong. Evaluation on stress intensity factor of crack under dynamic load using numerical manifold method. Chinese Journal of Theoretical and Applied Mechanics, 2014, 46(5): 730-738 (in Chinese))
[9]  Munjiza A, Owen DRJ, Bicanic N. A combined finite-discrete element method in transient dynamics of fracturing solids. Engineering Computations, 1995, 12(2): 145-174
[10]  Munjiza A. The Combined Finite-Discrete Element Method. New York: John Wiley and Sons, 2004: 277-290
[11]  Owen DRJ, Feng YT, De Souza Neto EA, et al. The modeling of multi-fracturing solids and particulate media. International Journal for Numerical Methods in Engineering, 2004, 60(efeq1): 317-339
[12]  Li SH, Zhang YN. Feng C. A spring system equivalent to continuum model. In: The Proc. of The Fifth International Conference on Discrete Element Methods. London, 2010. 75-85
[13]  冯春, 李世海, 姚再兴. 基于连续介质力学的块体单元离散弹簧法研究. 岩石力学与工程学报, 2010, 29(增刊1): 2690-2704 (Feng Chun, Li Shihai, Yao Zaixing. Study of block-discrete-spring method based on continuum mechanics. Chinese Journal of Rock Mechanics and Engineering, 2010, 29(Supp.1): 2690-2704 (in Chinese))
[14]  王杰, 李世海, 周东, 等. 模拟岩石破裂过程的块体单元离散弹簧模型. 岩土力学, 2013, 34(8): 2355-2362 (Wang Jie, Li Shihai, Zhou Dong, et al. A block-discrete-spring model to simulate failure process of rock. Rock and Soil Mechanics, 2013, 34(8): 2355-2362 (in Chinese))
[15]  常晓林, 胡超, 马刚, 等. 模拟岩石失效全过程的连续-非连续变形体离散元方法及应用. 岩石力学与工程学报, 2011, 30(10): 2004-2011 (Chang Xiaolin, Hu Chao, Ma Gang, et al. Continuous-discontinuous deformable discrete element method to simulate the whole failure process of rock masses and application. Chinese Journal of Rock Mechanics and Engineering, 2011, 30(10): 2004-2011 (in Chinese))
[16]  马刚, 周创兵, 常晓林, 等. 岩石破坏全过程的连续-离散耦合分析方法. 岩石力学与工程学报, 2011, 30(12): 2444-2455 (Ma Gang, Hu Chao, Chang Xiaolin, et al. Continuous-discontinuous coupling analysis for whole failure process of rock. Chinese Journal of Rock Mechanics and Engineering, 2011, 30(12): 2444-2455 (in Chinese))
[17]  侯艳丽, 周元德, 张楚汉. 用3D离散元实现I/II型拉剪混凝土断裂的模拟. 工程力学, 2007, 24(3): 1-7 (Hou Yanli, Zhou Yuande, Zhang Chuhan. I/II tensile shear mixed mode fracture simulation by 3D discrete element method. Engineering Mechanics, 2007, 24(3): 1-7 (in Chinese))
[18]  张青波, 李世海, 冯春. 四节点矩形弹簧元及其特性研究. 岩土力学, 2012, 33(11): 3497-3502 (Zhang Qingbo, Li Shihai, Feng Chun. Study of four-node rectangular spring element and its properties. Rock and Soil Mechanics, 2012, 33(11): 3497-3502 (in Chinese))
[19]  张青波, 李世海, 冯春, 等. 基于SEM的可变形块体离散元法研究. 岩土力学, 2013, 34(8): 2385-2392 (Zhang Qingbo, Li Shihai, Feng Chun, et al. Study of deformable block discrete element method based on SEM. Rock and Soil Mechanics, 2013, 34(8): 2385-2392 (in Chinese))
[20]  张楚汉, 金峰. 岩石和混凝土离散-接触-断裂分析. 北京: 清华大学出版社, 2008 (Zhang Chuhan, Jin Feng. Discrete-Contact-Fracture Analysis of Rock and Concrete. Beijing: Tsinghua University Press, 2008 (in Chinese))
[21]  Hillerborg A, Modeer M, Petersson PE. Analysis of crack formation and crack growth in concrete by means of fracture mechanics and finite elements. Cement and Concrete Research, 1976, 6(6): 773-782
[22]  Wells GN, Sluys LJ. A new method for modeling cohesive cracks using finite elements. International Journal for Numerical Methods in Engineering, 2001, 50(12): 2667-2682
[23]  Carpinteri A, Colombo G. Numerical analysis of catastrophic softening behavior (snap-back instability). Computer & Structures, 1989, 31(4): 607-636
[24]  Ning YJ, An XM, Ma GW. Footwall slope stability analysis with the numerical manifold method. International Journal of Rock Mechanics & Mining Sciences, 2001, 48(6): 964-975
[25]  Nooru-Mohamed MB. Mixed-mode fracture of concrete: An experimental approach. [PhD Thesis]. Delft: University of Technology, 1992
[26]  Oliver J, Huespe AE, Samaniego E, et al. Continuum approach to the numerical simulation of material failure in concrete. International Journal for Numerical and Analytical Methods in Geomechanics, 2004: 28(7-8): 609-632
[27]  Zi G, Rabczuk T, Wall W. Extended meshfree methods without branch enrichment for cohesive cracks. Computational Mechanics, 2007, 40(2): 367-382

Full-Text

Contact Us

service@oalib.com

QQ:3279437679

WhatsApp +8615387084133