不同粒级充填体单轴压缩条件下力学性能及声发射特性研究

发布时间：2018-03-23 07:49

本文选题：不同粒级　切入点：充填体　出处：《江西理工大学》2015年硕士论文　论文类型：学位论文

【摘要】：为了充分认知充填体的力学性能和声发射特性及探讨组成岩石类材料粒级的不同对声发射平静期的影响,本文主要以室内试验为研究手段结合理论分析对灰砂比为1:4、浓度70%、养护期为28天的0.074-0.08mm、0.08-0.16mm、0.16-0.25mm、0.25-0.5mm及全尾砂五种不同粒级的充填体进行了单轴压缩声发射试验,主要从以下的几个方面进行了研究和探讨:第一,单轴压缩条件下不同粒级充填体的力学性能测试,包括变形特性、破坏形式及强度特性;第二,单轴压缩条件下不同粒级充填体的声发射特性;第三,不同粒级充填体声发射平静期研究。得到以下结论:(1)不同粒级充填体变形特征一致,都经历了四个变形特征:①初始压密;②弹性变形;③塑性变形(裂纹产生及扩展);④裂纹加速扩展至试件破坏。不同粒级的充填体破坏的形式基本一致,且破坏后都表现为较好的延性。(2)0.074-0.08mm、0.08-0.16mm、0.16-0.25mm三种粒级充填体的单轴抗压强度分别为2.358MPa、3.124MPa、3.772MPa依次增加,而0.25-0.5mm粒级充填体单轴抗压强度为2.602MPa,得出0.25-0.5mm粒级范围对充填体强度产生负面影响。(3)声发射平静期受粒级不同的影响较大。在0.25-0.5mm粒级充填体声发射试验中未监测到明显的声发射平静期现象。(4)0.074-0.08mm粒级充填体、0.08-0.16mm粒级充填体、0.16-0.25mm粒级充填体出现平静期的应力百分比区间分别为87.5%-95.3%、64.4%-84.3%、37.6%-97.6%,随着粒级的增大,出现平静期的应力百分比范围也增大。(5)平静期耗时与应力峰值历时比和充填体粒级之间的没有明显的规律。
[Abstract]:In order to fully understand the mechanical properties and acoustic emission characteristics of the filling body and to explore the influence of the particle size of the rock material on the acoustic emission quiescent period, In this paper, using the laboratory test as the research means, combined with theoretical analysis, the uniaxial compression acoustic emission tests have been carried out on five kinds of filling bodies with a ratio of 1: 4 to 1: 4, a concentration of 70 and a curing period of 28 days, which are 0.074-0.08 mm ~ 0.08-0.16 mm ~ 0.16 mm ~ 0.16 mm ~ 0.25 mm ~ 0.25-0.5 mm and full-tailing sand respectively. This paper mainly discusses the following aspects: first, the mechanical properties of different grain-size fillers under uniaxial compression conditions, including deformation characteristics, failure form and strength characteristics; second, Under uniaxial compression condition, the acoustic emission characteristics of different grain-grade filling bodies are studied. Thirdly, the acoustic emission quiet period of different grain-grade filling bodies is studied. The following conclusions are obtained: 1) the deformation characteristics of different grain-grade filling bodies are the same. All of them have experienced four deformation characteristics: 1, initial compaction, 2 elastic deformation and 3 plastic deformation (crack generation and crack propagation accelerate to specimen failure. The failure patterns of different grain-size filling bodies are basically the same. The results show that the uniaxial compressive strength of the three kinds of filling bodies is 2.358 MPA, 3.124 MPA and 3.772 MPA, respectively, and the ductility is 0.074-0.08mm, 0.08-0.16mm, 0.16-0.25mm, and the uniaxial compressive strength is 3.772 MPA. However, the uniaxial compressive strength of 0.25-0.5mm granular filling is 2.602MPa. It is concluded that the range of 0.25-0.5mm particles has a negative effect on the strength of filling body. The stress percentage ranges of 0.16-0.25mm grain filling body in the quiet period are 87.5-95.3mm and 64.4- 84.3mm respectively, and the ratio of 37.6- 97.6mm is increased with the increase of grain size, and the stress percentage of 0.08-0.16mm grain filling body is 0.08-0.16mm and 0.16-0.25mm. The stress percentage ranges from 87.5- 95.3mm to 64.4- 84.3mm, respectively, and from 0.08-0.16mm to 0.16mm. The percentage range of stress in the calming period is also increased. 5) there is no obvious rule between the time consuming and the peak stress duration ratio and the grain size of the filling body during the quiet period.
【学位授予单位】：江西理工大学
【学位级别】：硕士
【学位授予年份】：2015
【分类号】：TD853.34

【引证文献】