收稿日期: 2019-07-09
修回日期: 2020-01-19
网络出版日期: 2020-05-07
基金资助
国家自然科学基金青年基金项目“水—力耦合作用下卸荷诱导的裂隙体破断实验与灾变机理研究”(51704168);中国博士后科学基金项目“单轴压缩下渗透压动态传递—稳态作用的裂隙体断裂破坏试验与研究”(2016M602417);湖南省自然科学基金项目“渗流场长时稳定作用的裂隙体破断实验与机理研究”(2019JJ50528)
Fracture Test and Analysis of Rock-Mass Model with Prefabricated Defects
Received date: 2019-07-09
Revised date: 2020-01-19
Online published: 2020-05-07
为了探究内部缺陷形状由裂隙至圆孔的变化对类岩体脆性材料破断模式与特征的影响,构建了含缺陷的单轴压缩力学模型,并利用水泥砂浆材料制作类岩体试样,系统地研究了缺陷形状由裂隙至圆孔变化过程中含缺陷试件的强度变化特征和裂纹演化扩展机制。结果表明:当荷载方向与缺陷长轴垂直时,缺陷周边应力集中在长短轴端点处且与缺陷无关;缺陷对试样峰值强度影响较为明显,在缺陷形状由裂隙向圆孔变化的过程,峰值强度降低幅度逐渐增大;缺陷变化对试样的裂纹起裂与裂纹扩展的影响不显著;缺陷试样的最终破坏模式可划分为剪切破坏和拉—剪混合破坏,当m值大于0.60时破坏模式为剪切破坏,当m值小于0.33时破坏模式为拉—剪混合破坏。
张栩栩 , 杨仕教 , 曾佳君 , 罗可 , 蒲成志 . 含预制缺陷类岩体模型破断试验与分析[J]. 黄金科学技术, 2020 , 28(2) : 255 -263 . DOI: 10.11872/j.issn.1005-2518.2020.02.129
In the process of formation of natural rock-mass,a large number of cracks,holes and other original defects often occur in interior,the internal defects of rock have a significant impact on the mechanical properties of rock-mass.Therefore,it is important to study the initiation,propagation and fracture of cracks in defective rock materials and rock-mass materials for practical engineering.Hence we explored the influence of the change of internal defects from cracks to holes on the fracture mode and characteristics of rock-mass materials by combining theory with experiment.Firstly the mechanical model of uniaxial compression was constructed and the stress at the hole edge was solved by using the conformal angle mapping method,then the uniaxial compression test was carried out on the defective rock samples made of cement mortar materials.The rock-mass specimens were made by mixing 325# white cement,river sand,and water at a mass ratio of 5∶5∶2,the size of the defective sample after forming is 200 mm×150 mm×50 mm.The defects were created by inserting 3D printing materials into cement mortar paste and removing them during curing,the long axis 2a is 40 mm,the short axis 2b is change values for 1,10,20,30,40 mm,hence the corresponding m [m=(a-b)/(a+b)] values were 0.95,0.60,0.33,0.14 and 0.Uniaxial compression of defect specimens by using the rock mechanics servo-controlled testing system after standard conservation were carried out.The test results show that:(1)Under uniaxial compression,when m is 0 the uniaxial compressive strength of the defective rock-mass is the lowest.The uniaxial compressive strength of the defective specimen increases gradually with the increase of m value,and the peak strength of the defective specimen decreases gradually with the increase of m value.(2)In the process of uniaxial compression fracture of defective rock-mass,the initial tension crack is initiated at the end of the short axis of the defect.With the increase of m value,the initiation position gradually moves to both ends of the long axis,and the crack develops along the direction of the principal stress.Under the action of continuous load,shear cracks are initiated near or far from the long axis of the defect,and the shear crack propagates continuously with the increase of load.In the later stage of crack propagation,spalling phenomenon at the end of the long axis when the m value is large.(3)After uniaxial compression fracture the defective rock-mass will have two fracture modes, namely shear failure and tension-shear mixed failure.When m is greater than 0.60,the failure mode is shear failure,others will happen tension-shear mixed failure.
1 | 杨小彬,宋义敏,赵同彬.岩石变形破坏演化力学分析[M].北京:煤炭工业出版社,2016. |
1 | Yang Xiaobin,Song Yimin,Zhao Tongbin.Mechanics Analysis of Deformation and Failure of Rock[M].Beijing:China Coal Industry Publishing House,2016. |
2 | Wang T T,Huang T H.A constitutive model for the deformation of a rock mass containing sets of ubiquitous joints[J].International Journal of Rock Mechanics and Mining Sciences,2009,46(3):521-530. |
3 | Tang C A,Wong R H C,Chau K T,et al.Modeling of compression-induced splitting failure in heterogeneous brittle porous solid [J].Engineering Fracture Mechanics,2005,75(4):597-615. |
4 | 陈昊然,曹平,冉龙威.含齿形裂隙类岩石材料单轴压缩试验研究[J].黄金科学技术,2019,27(3):398-405. |
4 | Chen Haoran,Cao Ping,Ran Longwei.Experimental study of rock-like material with zigzag fracture under uniaxial compression[J].Gold Science and Technology,2019,27(3):398-405. |
5 | 李世愚,和泰名,尹祥础.岩石断裂力学[M]. 北京:科学出版社,2015. |
5 | Li Shiyu,He Taiming,Yi Xiangchu.The Fracture Toughness of Rock[M]. Beijing:Science Press,2015. |
6 | 张敦福,朱维申,李术才,等.围压和裂隙水压力对岩石中椭圆裂 纹初始开裂的影响[J].岩石力学与工程学报,2004,23(增2):4721-4725. |
6 | Zhang Dunfu,Zhu Weishen,Li Shucai,et al.Influence of confining pressure and fissure water pressure on initial opening for ellipse fracture[J].Chinese Journal of Rock Me-chanics and Engineering,2004,23(Supp.2):4721-4725. |
7 | 陈 新,彭 曦,李东威,等.基于两种破裂判据的裂隙岩体单轴压缩起裂分析[J].工程力学,2013,30(10):227-235. |
7 | Chen Xin,Peng Xi,Li Dongwei,et al.Analysis on cracking mechanism of fractured rock masses under uniaxial compression based on the two cracking criteria[J].Engineering Mechanics,2013,30(10):227-235. |
8 | 张科,刘享华,李昆,等.含孔多裂隙岩石力学特性与破裂分形维数相关性研究[J].岩石力学与工程学报,2018,37(12):2785-2794. |
8 | Zhang Ke,Liu Xianghua,Li Kun,et al.Investigation on the correlation between mechanical characteristics and fracturing fractal dimension of rocks containing a hole and multi-flaws[J].Chinese Journal of Rock Mechanics and Engineering,2018,37(12):2785-2794. |
9 | 刘红岩,黄妤诗,李楷兵,等.预制节理岩体试件强度及破坏模式的试验研究[J].岩土力学,2013,34(5):1235-1241,1246. |
9 | Liu Hongyan,Huang Yushi,Li Kaibing,et al.Experimental study on strength and failure mode of prefabricated jointed rock mass specimens[J].Rock and Soil Mechanics,2013,34(5):1235-1241,1246. |
10 | 李地元,朱泉企,李夕兵.孔洞形状对大理岩渐进破坏力学特性影响研究[J].地下空间与工程学报,2018,14(1):58-66. |
10 | Li Diyuan,Zhu Quanqi,Li Xibing.Research on the effect of cavity shapes for the progressive failure and mechanical behavior of marble[J].Chinese Journal of Underground Space and Engineering,2018,14(1):58-66. |
11 | 林鹏,黄凯珠,王仁坤,等.不同角度单裂纹缺陷试样的裂纹扩展与破坏行为[J].岩石力学与工程学报,2005,24(增 2):5652-5657. |
11 | Lin Peng,Huang Kaizhu,Wang Renkun,et al.Crack growth mechanism and failure behavior of specimen containing single flaw with different angles[J].Chinese Journal of Rock Mechanics and Engineering,2005,24(Supp.2):5652-5657. |
12 | 赵程,刘丰铭,杨磊,等.岩石单裂纹扩展及损伤演化规律的数值模拟研究[J].重庆交通大学学报(自然科学版),2016,35(5):22-27. |
12 | Zhao Cheng,Liu Fengming,Yang Lei,et al.Numerical simulation of single crack propagation and damage evolution mechanism of rock specimens [J].Journal of Chong-qing Jiaotong University (Science and Technology),2016,35(5):22-27. |
13 | 李响,怀震,李夕兵,等.基于裂纹扩展模型的脆性岩石破裂特征及力学性能研究[J].黄金科学技术,2019,27(1):41-51. |
13 | Li Xiang,Huai Zhen,Li Xibing,et al.Study on fracture characteristics and mechanical properties of brittle rock based on crack propagation model[J].Gold Science and Technology,2019,27(1):41-51. |
14 | Niu S J,Jing H W,Hu K.Numerical investigation on the sensitivity of jointed rock mass to various factors[J].Mining Science and Technology,2010,20(4):530-534. |
15 | 蒲成志,曹平,陈瑜,等.不同裂隙相对张开度下类岩石材料断裂试验与破坏机理[J].中南大学学报(自然科学版),2011,42 (8):2394-2399. |
15 | Pu Chengzhi,Cao Ping,Chen Yu,et al.Fracture test and failure mechanism of rock-like material of relatively different fracture apertures[J].Journal of Central South University( Science and Technology Edition),2011,42 (8):2394-2399. |
16 | 谢林茂,朱万成,王述红,等.含孔洞岩石试样三维破裂过程的并行计算分析[J].岩土工程学报,2011,33(9):1447-1455. |
16 | Xie Linmao,Zhu Wancheng,Wang Shuhong,et al.Three-dimensional parallel computing on failure process of rock specimen with a pre-existing circular opening[J].Chinese Journal of Geotechnical Engineering,2011,33(9):1447-1455. |
17 | 杨圣奇,吕朝辉,渠 涛.含单个孔洞大理岩裂纹扩展细观试验和模拟[J].中国矿业大学学报,2009,38(6):774-781. |
17 | Yang Shengqi,Chaohui Lü,Qu Tao.Investigations of crack expansion in marble having a single pre-existing hole:Experiment and simulations[J].Journal of China Un-iversity of Mining and Technology,2009,38(6):774-781. |
18 | 杨圣奇,刘相如,李玉寿.单轴压缩下含孔洞裂隙砂岩力学特性试验分析[J].岩石力学与工程学报,2012,31(增 2):3539-3546. |
18 | Yang Shengqi,Liu Xiangru,Li Yushou.Experimental analysis of mechanical behavior of sandstone containing hole and fissure under uniaxial compression[J].Chinese Journal of Rock Mechanics and Engineering,2012,31(Supp.2):3539-3546. |
19 | 朱泉企,李地元,李夕兵.含预制椭圆形孔洞大理岩变形破坏力学特性试验研究[J].岩石力学与工程学报,2019,38(增1):2724-2733. |
19 | Zhu Quanqi,Li Diyuan,Li Xibing.Experimental study on failure and mechanical characteristics of marble containing a prefabricated elliptical hole [J].Chinese Journal of Rock Mechanics and Engineering,2019,38(Supp.1):2724-2733. |
20 | 杜明瑞,靖洪文,苏海健,等.含预制椭圆形孔洞砂岩强度及破坏特征试验研究[J].中国矿业大学学报,2016,45(6):1164-1171. |
20 | Du Mingrui,Jing Hongwen,Su Haijian,et al.Experimental study of strength and failure characteristics of sandstone containing prefabricated elliptical hole[J].Journal of China University of Mining and Technology,2016,45(6):1164-1171. |
21 | Martin D C.Seventeenth Canadian Geotechnical Colloquium:The effect of cohesion loss and stress path on brittle rock strength[J].Canadian Geotechnical Journal,1997,34(5):698-725. |
/
〈 | 〉 |