温度作用后大理岩三轴卸荷细观破坏特征研究

笔者采用RMT-150C岩石力学试验系统开展了常温以及200℃作用后大理岩试件在卸荷路径下的单轴、三轴压缩试验,结合SEM电镜电镜扫描试验的结果,引用了损伤力学的概念,分析了大理岩试件在不同温度作用后的宏、细观破坏特征。试验结果表明:卸荷路径下的试件,受200℃温度作用后,试件的破碎程度普遍要比常温试件的要高;用纵波波速比商法定义了温度损伤,损伤因子变化和强度降低的变化成反相关;温度作用后大理岩的微观破坏特性的变化主要表现在气孔变大变多,张剪性、缩聚性微裂纹变多。

Characteristics of Microscopic Damage of Marble Triaxial Unloading under Temperature Effect

The author uses RMT-150C rock mechanics test system to carry out the uniaxial and triaxial compression test of marble specimens under unloading path at room temperature and after 200 ~C role. Combined with the results of SEM electron microscope trial, the concept of damage mechanics is introduced to analyze the macroscopic and microscopic characteristics of the marble specimens at different temperatures role. The test results showed that： under the unloading path and after effect by temperature 200 ~C, the degree of fragmentation of the specimen was generally higher than normal temperature of the specimen; commercial longitudinal wave ratio was used to define temperature injury, and the damage factor changes and strength reduction changes were inversely related; the changes of microscopic damage characteristics mainly showed that the pores became bigger and more and the tension-shear resistance, condensation resistance microcracks increased.