基于改进Weibull分布模型的岩石单轴压缩变形破裂规律研究

摘要
图/表
参考文献
相关文章 (15)

全文: PDF (2037 KB) HTML (1 KB)
输出: BibTeX | EndNote (RIS)

摘要岩石的单轴压缩响应受岩石微细观结构、边界条件、试件形状等影响，呈现出测量强度和变形特性的离散性。针对上述问题，基于连续介质力学的方法，采用非线性损伤本构关系模拟岩石材料的力学响应，在常规Weibull随机分布模型基础上，引入空间相关尺度因子，建立考虑岩石空间相关特性的细观力学模型。采用改进的Weibull分布模型，对不同形状的非均质岩石试件进行单轴压缩数值试验，研究不同加载边界对岩石破损行为的影响，结果表明：端部摩擦、试件形状会影响岩石受压的变形特征及破裂形态，即使试件端部存在较小的摩擦，形状效应仍然存在。为减小单轴压缩试验结果的离散性，需尽量减小端部效应，同时，增加试件的高宽比。

	服务

	把本文推荐给朋友
	加入我的书架
	加入引用管理器
	E-mail Alert
	RSS
	作者相关文章

关键词 ：岩石力学, 单轴压缩, 空间相关尺度, 端部效应, 形状效应

Abstract：Abundant test results have shown that the deformation and failure response of rock material under uniaxial compression is strongly dependent on its internal structure，boundary conditions，specimen geometry，etc. This study presents a mesoscale numerical model for rock material based on continuum mechanics，and a nonlinear damage material model is adopted to describe the deformation and failure behaviors of each mesoscale finite element. To consider the spatial correlation character of physical and mechanical properties of realistic rock material as commonly observed，a spatial correlation length factor is introduced into the traditional Weibull random distribution model. Based on the established improved mesoscale random model，a series of numerical uniaxial compression tests are conducted to investigate the effects of end friction and specimen geometry on the progressive failure response of rock specimens. The results show that the end friction and specimen slenderness ratio can significantly affect the load-deformation curves and fracture patterns. The effect of specimen geometry plays a vital role even when the end friction is reduced to a small value. The mesoscale numerical study results indicate that experimental discrepancy may be diminished by lowering the end friction and increasing the specimen height/width ratio in the uniaxial compression test.

Key words： rock mechanics uniaxial compressive strength spatial correlation length end effect geometry effect

收稿日期: 2013-05-22

引用本文:

唐欣薇1，2，周元德3，4. 基于改进Weibull分布模型的岩石单轴压缩变形破裂规律研究[J]. 岩石力学与工程学报, 2014, 33(sl): 2802-2807.
TANG Xinwei1，2，ZHOU Yuande3，4. STUDY OF ROCK UNIAXIAL COMPRESSION DEFORMATION AND FAILURE CHARACTER BASED ON AN IMPROVED WEIBULL DISTRIBUTION MODEL. , 2014, 33(sl): 2802-2807.

链接本文:

http://www.rockmech.org/CN/Y2014/V33/Isl/2802

[4]	MOGI K. Dilatancy of rocks under general triaxial stress states with special reference to earthquakes precursors[J]. Journal of Physics of the Earth，1977，25：203-217. " target="_blank">
[8]	Itasca Consulting Group，Inc.. PFC3D user?s guide[R]. Mineapolis：Itasca Consulting Group，Inc.，2000. " target="_blank">
[10]	CHEN S，YUE Z Q，THAM L G. Digital image-based numerical modeling method for prediction of inhomogeneous rock failure[J]. International Journal of Rock Mechanics and Mining Sciences，2004，41(6)：939-957.
[18]	PELLS P J. Uniaxial strength testing[C]// HUDSON J. ed. In Comprehensive Rock Engineering. Oxford：Pergamon Press，1993：75-97. " target="_blank">
[1]	HUDSON J A，BROWN E T，FAIRHURST C. Shape of the complete stress-strain curve for rock[C]// Stability of Rock Slopes. Proceedings of the 13th Symposium on Rock Mechanics. Urbana：University of Illiois，ASCE，1971：773-795. " target="_blank">
[2]	杨圣奇，苏承东，徐卫亚. 岩石材料尺寸效应的试验和理论研究[J]. 工程力学，2005，22(4)：112-118.(YANG Shengqi，SU Chengdong，XU Weiya. Experimental and theoretical study of size effect of rock material[J]. Engineering Mechanics，2005，22(4)：112-118.(in Chinese))
[3]	MOGI K. Effect of the triaxial stress system on the failure of dolomite and limestone[J]. Tectonophysics，1971，11(2)：111-127. " target="_blank">
[5]	潘鹏志，周辉，冯夏庭. 加载条件对不同尺寸岩石单轴压缩破裂过程的影响研究[J]. 岩石力学与工程学报，2008，27(增2)：3 636- 3 642.(PAN Pengzhi，ZHOU Hui，FENG Xiating. Research on effect of loading conditions on failure processes of rocks with different sizes under uniaxial compression[J]. Chinese Journal of Rock Mechanics and Engineering，2008，27(Supp.2)：3 636-3 642.(in Chinese))
[6]	TANG C A，LIU H，LEE P K K，et al. Numerical studies of the influence of microstructure on rock failure in uniaxial compression. part 2：Effect of heterogeneity[J]. International Journal of Rock Mechanics and Mining Sciences，2000，37(4)：555-569. " target="_blank">
[7]	SCHLANGEN E，VAN MIER J G M. Simple lattice model for numerical simulation of concrete material and structures[J]. Materials and Structures，1992，25(9)：534-542. " target="_blank">
[9]	于庆磊，唐春安，唐世斌. 基于数字图像的岩石非均匀性表征技术及初步应用[J]. 岩石力学与工程学报，2007，26(3)：551-559.(YU Qinglei，TANG Chun?an，TANG Shibin. Digital image based characterization method of rock?s heterogeneity and tis primary application[J]. Chinese Journal of Rock Mechanics and Engineering，2007，26(3)：551-559.(in Chinese))
[11]	KWN A K H，MORA C F，CHAN H C. Particle shape analysis of coarse aggregate using digital image processing[J]. Cement and Concrete Research，1999，29(9)：1 403-1 410. " target="_blank">
[12]	刘延保，曹树刚，刘玉成. 基于LS-SVM的岩石细观图像分析方法探讨[J]. 岩石力学与工程学报，2008，27(5)：1 059-1 065.(LIU Yanbao，CAO Shugang，LIU Yucheng. Discussion on analytical method for LS-SVM based mesoscopic rock images[J]. Chinese Journal of Rock Mechanics and Engineering，2007，27(5)：1 059- 1 065.(in Chinese))
[13]	LEE J，FENVES G L. Plastic-damage model for cyclic loading of concrete structures[J]. Journal of Engineering Mechanics，1998，124(8)：892-900. " target="_blank">
[14]	唐欣薇，张楚汉. 混凝土细观力学模型研究：非均质影响[J]. 水力发电学报，2009，28(4)：56-62.(TANG Xiwei，ZHANG Chuhan. Meso-scale modeling of concrete：effects of heterogeneity[J]. Journal of Hydroelectric Engineering，2009，28(4)：56-62.(in Chinese))
[15]	GRIFFITHS D V，GORDON F A. Probabilistic slope stability analysis by finite elements[J]. Journal of Geotechnical and Geoenvironmental Engineering，2004，130(5)：507-518. " target="_blank">
[16]	唐欣薇，周元德，张楚汉. 考虑空间相关尺度特征的细观力学模型及其应用[J]. 岩土力学，2012，33(7)：2 021-2 026.(TANG Xinwei，ZHOU Yuande，ZHANG Chuhan. A mesomechanical model with spatial correlation scale character and its application[J]. Rock and Soil Mechanics，2012，33(7)：2 021-2 026.(in Chinese))
[17]	MOGI K. Experimental rock mechanics[M]. London：Taylor and Francis，2006：6-11. " target="_blank">