含交叉多裂隙类岩石材料单轴压缩力学性能研究

 以类岩石材料模拟岩体，考虑了主次多裂隙、等长多裂隙两类交叉多裂隙形式，制作含交叉多裂隙试件，对试件进行单轴压缩实验，研究了含交叉多裂隙岩体在单轴压缩下的力学性能。研究表明：含2条交叉裂隙试件强度高于含单一裂隙试件，当裂隙数量超过2条(不含)时，含主次多裂隙试件峰值强度与含单一裂隙试件接近，含等长多裂隙试件的峰值强度及试件破坏所需外力功都低于含单一裂隙试件；次裂隙数量增加对含主次多裂隙试件强度影响不明显，裂隙数量增加对含等长多裂隙试件的强度降低作用非常明显；绝大部分含交叉多裂隙试件峰值强度对应应变低于含单一裂隙试件；含主次多裂隙试件起裂应力高于含单一裂隙试件，大部分含等长多裂隙试件起裂应力低于含单一裂隙试件；含单一裂隙试件破坏面为剪切裂隙，含交叉多裂隙试件破坏面以张拉裂隙为主。

THE UNIAXIAL COMPRESSION MECHANICAL PROPERTY OF ROCK-LIKE MATERIAL WITH INTERSECTING MULTI-FLAWS

In this work the uniaxial compression mechanical property of rock mass with intersecting multi-flaws are studied with rock-like material specimens. There are two kinds of intersecting multi-flaws taken into consideration--one comprises the main flaw and the secondary flaws，the other one is composed of multi-flaws with the same length of main flaw. The specimens are tested under the uniaxial compression situation. The test results show that：(1) When there are 2 intersecting flaws，the strength of specimen with intersecting multi-flaws is higher than that of specimen with a single flaw. When there are more than 2 intersecting flaws，the strength values of specimen with intersecting multi-flaws composed of a main flaw and secondary flaws are almost same with that of specimen with a single flaw. When there are more than 2 intersecting flaws and the flaws have the same length with the main flaw，the strength and the work to make the specimen failure are less than those of specimen with a single flaw. (2) The increasing number of secondary flaws has little influence on the strength of specimen with intersecting multi-flaws composed of a main flaw and secondary flaws，the increasing number of flaws have great influence on the strength of specimen with intersecting multi-flaws composed of flaws with the same length to main flaw. (3) Most of the strain values correspondent to the strength peak of specimens with intersecting multi-flaws are lower than that of specimen with a single flaw. (4) The fracture initial stress values of specimen with intersecting multi-flaws composed of a main flaw and secondary flaws are higher than that of specimen with a single flaw. Most of the fracture initial stress values of specimens with intersecting multi-flaws composed of flaws with the same length of main flaw are lower than that of specimen with a single flaw. (5) The failure surface of specimen with a single flaw is shear crack，and most of failure surfaces of specimens with intersecting multi-flaws are tense cracks.