两种环境下贺兰山岩石物理力学特性试验研究

Experimental study on physical and mechanical properties of rock in Helan Mountain in two environments

针对两种环境下贺兰山遗址区岩石冻融损伤的问题,本文首先对贺兰山遗址区的岩样进行了干燥和pH为2时两种环境下的冻融循环试验,设置循环周期分别为0、10、20、30和40次,测量岩样的质量、有效孔隙率和纵波波速,分析对比不同环境下冻融循环周期对它们影响的异同;然后开展单轴压缩试验,绘制应力-应变曲线、计算弹性模量并分析其变化规律;最后对比两种环境下岩样的破坏形态。研究结果表明,两组岩样的质量、有效孔隙率和纵波波速均有所下降,且pH为2组岩样的降低程度更大;与经历相同冻融周期的干燥组岩样相比,pH为2组岩样的单轴抗压强度更低,破损程度也更为明显。

In view of freeze-thaw damage of rock in Helan Mountain site area under two environments, firstly, the freezethaw cycle tests were carried out on the rock samples from Helan Mountain site under the conditions of drying and pH 2,and the cycles were set as 0, 10, 20, 30 and 40 times, respectively. The mass, effective porosity and longitudinal wave velocity of rock samples were measured. The similarities and differences of the effects of freeze-thaw cycle under different conditions were investigated and compared. Then, uniaxial compression tests were performed. Stress-strain curves of rocks were obtained, the elastic modulus were calculated, and their variation laws were analyzed. Finally, the failure modes of the rock samples in the two environments were compared. The results show that the mass, effective porosity and longitudinal wave velocity of rock samples in two groups decreased, and the reduction degree of the group pH 2 of rock samples was more significant. The uniaxial compressive strength of rock samples in group pH 2 was lower and the damage degree was more serious than that of rock samples in dry group undergoing the same freeze-thaw cycles.