节理充填物厚度对运动裂纹扩展的影响

宋彦琦; 李向上; 刘济琛; 王鹏懿

doi:10.11883/bzycj-2019-0358

节理充填物厚度对运动裂纹扩展的影响

doi: 10.11883/bzycj-2019-0358

中国矿业大学（北京）力学与建筑工程学院，北京 100083

基金项目: 国家自然科学基金联合基金（U1704242）；国家重点研发计划（2018YFC0808402）

详细信息

作者简介:
宋彦琦（1969－　），女，博士，教授，songyq@cumtb.edu.cn

通讯作者:
李向上（1991－　），男，博士研究生，xiangshang_li@126.com

中图分类号: O346.1
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- 被引次数: 0
出版历程
- 收稿日期: 2019-09-17
- 修回日期: 2019-10-28
- 网络出版日期: 2020-06-25
- 刊出日期: 2020-08-01

Effects of joint filling thickness on crack propagation behaviors

School of Mechanics and Civil Engineering, China University of Ming and Technology (Beijing), Beijing 100083, China

摘要

摘要: 为研究冲击载荷作用下节理充填物厚度对裂纹扩展行为的影响，以石膏为有机玻璃预制裂纹充填物，利用新型数字激光动态焦散线实验系统，对3种不同节理充填物厚度的有机玻璃进行三点弯冲击实验。实验结果表明，相同冲击载荷作用下，竖向预制裂纹均竖直向上扩展，是典型的Ⅰ型裂纹，充填物越厚，竖向裂纹越容易起裂。竖直裂纹扩展至水平预制裂纹后，充填物厚度为1、3、5 mm的试件的水平预制裂纹汇聚能量的时间分别为433、2 200、2 580 μs，起裂时的应力强度因子分别为635.2、742.4、906.8 kN/m^3/2，表明充填物越厚，水平裂纹越难起裂。水平预制裂纹扩展过程中共发生2次曲裂，是典型的Ⅰ-Ⅱ复合型裂纹，节理充填物越厚，其扩展轨迹越弯曲；当裂纹扩展至距离试件上边界3 mm时，扩展方向偏离第1次裂纹曲裂切线而朝向试件上边界扩展，试件最终断裂，测量发现充填物厚度为1、3、5 mm的试件的断裂点与冲击载荷作用点的距离分别为16.5、11.0、6.0 mm。
- 节理充填物 /
- 动焦散线 /
- 冲击载荷 /
- 应力强度因子
Abstract: To explore the effects of the thickness of joint-filling material on the dynamic fracture properties of cracks under impact load, the gypsum was used as the material filled into the prefabricated cracks in polymethyl methacrylate (PMMA) specimens, three-point bending impact tests were conducted on the PMMA specimens with different joint filling thicknesses by using a novel digital laser dynamic caustics experimental system. The experimental results show that the vertical prefabricated cracks propagate vertically upward toward the free surface under the same impact load, which is a tytical mode-Ⅰ crack, and the thicker the filling, the easier the vertical crack initiation. When the vertical crack propagates to the horizontal prefabricated crack, the energy gathering times of the horizontal prefabricated cracks in the specimens with a filling thickness of 1, 3 and 5 mm are 433, 2 200 and 2 580 μs, respectively. And the stress intensity factors of crack initiation are 635.2, 742.4 and 906.8 kN/m^3/2, respectively. It indicates that the thicker the filling, the more difficult the horizontal crack initiation. The horizontal prefabricated crack is a typical Ⅰ-Ⅱ composite crack. The thicker the joint filler, the more curved the propagation path of the horizontal prefabricated crack. When the distance between the crack and the upper boundary of the specimen is 3 mm, the horizontal crack propagates towards the upper boundary of the specimen, and the specimen finally breaks. It is found that the distances between the fracture points and the impact load points of the specimens with the filling thicknesses of 1, 3 and 5 mm are 16.5, 11.0 and 6.0 mm, respectively.
- joint filler /
- dynamic caustics /
- impact load /
- stress intensity factor

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图 1 焦散线成像原理

Figure 1. The principle of caustics formation

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图 2 落锤冲击加载平台

Figure 2. Drop-weight impact loading platform

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图 3 动态焦散系统光路

Figure 3. Optical light path of experimental system of dynamic caustics

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图 4 试件模型

Figure 4. Specimen model

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图 5 各试件断裂示意图

Figure 5. Fracture patterns of experimental specimens

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图 6 试样S_1-3中裂纹扩展过程动焦散斑图片

Figure 6. Photos of dynamic caustic spots in specimen S_1-3 during crack growth

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图 7 试样S_3-1中裂纹扩展过程动焦散斑图片

Figure 7. Photos of dynamic caustic spots in specimen S_3-1 during crack growth

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图 8 试样S_5-2中裂纹扩展过程动焦散斑图片

Figure 8. Photos of dynamic caustic spots in specimen S_5-2 during crack growth

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图 9 不同试样不同部位动态应力强度因子随时间的变化

Figure 9. Change of dynamic stress intensity factors at different positions of different specimens with time

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表 1 试件断裂破坏各阶段对应的开始时刻

Table 1. Start times corresponding to different stages of fracture failure of specimens

试件 t₁/μs t₂/μs t₃/μs t₄/μs t₅/μs

S_1-3 500 527 960 1 107 1 360
S_3-1 507 541 2 741 2 847 3 067
S_5-2 493 533 3 113 3 166 3 312

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参考文献(18)

[1]	蔡美峰. 岩石力学与工程[M]. 北京: 科学出版社, 2002: 125−128.
[2]	韩智铭, 乔春生, 涂洪亮. 含一组贯通节理岩体强度的各向异性分析 [J]. 中国矿业大学学报, 2017, 46(5): 1073–1083. DOI: 10.13247/j.cnki.jcumt.000741. HAN Z M, QIAO C S, TU H L. Analysis of strength anisotropy of rock mass with a set of persistent joints [J]. Journal of China University of Mining and Technology, 2017, 46(5): 1073–1083. DOI: 10.13247/j.cnki.jcumt.000741.
[3]	范勇, 江璐, 卢文波, 等. 圆形隧洞爆破荷载与瞬态卸荷作用围岩应变能效应研究 [J]. 岩石力学与工程学报, 2017, 36(8): 1855–1866. DOI: 10.13722/j.cnki.jrme.2017.0081. FAN Y, JIANG L, LU W B, et al. Strain energy characteristics of surrounding rock under blasting load and transient release of geostress during excavation of circular tunnel [J]. Chinese Journal of Rock Mechanics and Engineering, 2017, 36(8): 1855–1866. DOI: 10.13722/j.cnki.jrme.2017.0081.
[4]	杨仁树, 左进京, 方士正, 等. 圆孔缺陷对爆生裂纹扩展行为影响的试验研究 [J]. 振动与冲击, 2018, 37(12): 174–178. DOI: 10.13465/j.cnki.jvs.2018.12.026. YANG R S, ZUO J J, FANG S Z, et al. An experimental study on the effect of circular hole defect on crack propagation behavior of blast loading [J]. Journal of Vibration and Shock, 2018, 37(12): 174–178. DOI: 10.13465/j.cnki.jvs.2018.12.026.
[5]	KALTHOFF J F, WINKLER S, BEINERT J. The influence of dynamic effects in impact testing [J]. International Journal of Fracture, 1977, 13(4): 528–531. DOI: 10.1007/BF00034256.
[6]	KAWAGISHI Y, SHOZU M, HIROSE Y. Experimental evaluation of stress field around crack tip by caustic method [J]. Mechanics of Materials, 2001, 33(12): 741–757. DOI: 10.1016/S0167-6636(01)00077-1.
[7]	姚学锋, 熊春阳, 方竞. 含偏置裂纹三点弯曲梁的动态断裂行为研究 [J]. 力学学报, 1996, 28(6): 661–669. DOI: 10.3321/j.issn:0459-1879.1996.06.003. YAO X F, XIONG C Y, FANG J. Study of dynamic fracture behaviour on three point bend beam with off center edge crack [J]. Acta Mechanica Sinica, 1996, 28(6): 661–669. DOI: 10.3321/j.issn:0459-1879.1996.06.003.
[8]	杨鑫, 蒲传金, 廖涛, 等. 含不同充填物预制裂隙对爆炸裂纹扩展的影响 [J]. 爆炸与冲击, 2016, 36(3): 370–378. DOI: 10.11883/1001-1455(2016)03-0370-09. YANG X, PU C J, LIAO T, et al. Effect of prefabricated crack with different fillings on blasting cracks propagation [J]. Explosion and Shock Waves, 2016, 36(3): 370–378. DOI: 10.11883/1001-1455(2016)03-0370-09.
[9]	岳中文, 宋耀, 杨仁树, 等. 冲击荷载下深梁动态断裂行为的光弹性实验 [J]. 振动与冲击, 2017, 36(19): 236–241. DOI: 10.13465/j.cnki.jvs.2017.19.036. YUE Z W, SONG Y, YANG R S, et al. Photoelastic experiments on deep beam fracture behaviors under impact load [J]. Journal of Vibration and Shock, 2017, 36(19): 236–241. DOI: 10.13465/j.cnki.jvs.2017.19.036.
[10]	杨仁树, 苏洪, 龚悦, 等. 冲击作用下静止裂纹与运动裂纹相互作用的试验研究 [J]. 振动与冲击, 2018, 37(8): 107–112. DOI: 10.13465/j.cnki.jvs.2018.08.017. YANG R S, SU H, GONG Y, et al. Experimental study of interaction between stationary crack and moving crack under impact [J]. Journal of Vibration and Shock, 2018, 37(8): 107–112. DOI: 10.13465/j.cnki.jvs.2018.08.017.
[11]	李清, 于强, 徐文龙, 等. 应变片法确定I型裂纹动态应力强度因子试验研究 [J]. 岩土力学, 2018, 39(4): 1211–1218. DOI: 10.16285/j.rsm.2017.1581. LI Q, YU Q, XU W L, et al. Experimental research on determination of dynamic stress intensity factor of type-I crack using strain gage method [J]. Rock and Soil Mechanics, 2018, 39(4): 1211–1218. DOI: 10.16285/j.rsm.2017.1581.
[12]	杨立云, 张勇进, 孙金超, 等. 偏置裂纹对含双裂纹PMMA试件动态断裂影响效应研究 [J]. 矿业科学学报, 2017, 2(4): 330–335. DOI: 10.19606/j.cnki.jmst.2017.04.003. YANG L Y, ZHANG Y J, SUN J C, et al. The effect of offset distance on dynamic fracture behavior of PMMA with double cracks [J]. Journal of Mining Science and Technology, 2017, 2(4): 330–335. DOI: 10.19606/j.cnki.jmst.2017.04.003.
[13]	杨仁树, 岳中文, 董聚才, 等. 断续节理介质爆生裂纹扩展的动焦散实验研究 [J]. 中国矿业大学学报, 2008, 37(4): 467–472. DOI: 10.3321/j.issn:1000-1964.2008.04.007. YANG R S, YUE Z W, DONG J C, et al. Dynamic caustics experiment of blasting crack propagation in discontinuous jointed material [J]. Journal of China University of Mining and Technology, 2008, 37(4): 467–472. DOI: 10.3321/j.issn:1000-1964.2008.04.007.
[14]	TAKAHASHI K, ARAKAWA K. Dependence of crack acceleration on the dynamic stress-intensity factor in polymers [J]. Experimental Mechanics, 1987, 27(2): 195–199. DOI: 10.1007/BF02319474.
[15]	何庆芝, 郦正能. 工程断裂力学[M]. 北京: 北京航空航天大学出版社, 1993.
[16]	肖同社, 杨仁树, 庄金钊, 等. 节理岩体爆生裂纹扩展动态焦散线模型实验研究 [J]. 爆炸与冲击, 2007, 27(2): 159–164. DOI: 110.11883/1001-1455(2007)02-0159-06. XIAO T S, YANG R S, ZHUANG J Z, et al. Dynamic caustics model experiment of blasting crack developing on sandwich rock [J]. Explosion and Shock Waves, 2007, 27(2): 159–164. DOI: 110.11883/1001-1455(2007)02-0159-06.
[17]	郭东明, 刘康, 杨仁树, 等. 动静荷载对邻近巷道裂纹缺陷扰动的模拟实验 [J]. 爆炸与冲击, 2016, 36(3): 297–304. DOI: 10.11883/1001-1455(2016)03-0297-08. GUO D M, LIU K, YANG R S, et al. Simulated experiment of disturbance effect on crack defects of adjacent tunnel under dynamic and static load [J]. Explosion and Shock Waves, 2016, 36(3): 297–304. DOI: 10.11883/1001-1455(2016)03-0297-08.
[18]	杨仁树, 肖成龙, 丁晨曦, 等. 空孔与运动裂纹相互作用的动焦散线实验研究 [J]. 爆炸与冲击, 2020, 40(5): 052202. DOI: 10.11883/bzycj-2019-0091. YANG R S, XIAO C L, DING C X, et al. Experimental study on dynamic caustics of interaction between void and running crack [J]. Explosion and Shock Waves, 2020, 40(5): 052202. DOI: 10.11883/bzycj-2019-0091.