干湿循环作用下充填节理岩石压缩特性

为探明干湿循环作用对充填节理岩石压缩力学强度与变形破坏特征的影响，人工制备多种不同充填物的节理岩石试样，对其进行0(全程干燥)、1、5、10、15、20次干湿循环预处理，使试样产生一定的累积损伤；在此基础上，对充填节理岩石试样进行静态单轴压缩试验和动态冲击试验，并在动态冲击试验过程中借助高速摄像机观察充填节理岩石的冲击破坏特征。研究结果表明：随着干湿循环次数的增加，充填节理岩石的静态和动态抗压强度不断降低，且降低幅度逐渐变小，20次干湿循环作用后岩样的静态和动态抗压强度总劣化度均为20%~30%；通过拟合发现岩样的动态抗压强度降低规律符合指数函数分布；随着干湿循环次数的增加，静态破坏模式由劈裂破坏逐步发展为剪切破坏，动态冲击中充填节理岩石破碎程度和充填节理层粉碎飞溅程度加剧，验证了干湿循环作用会严重影响充填节理岩石的变形破坏特征和动态抗冲击能力；应力波透射系数随干湿循环次数的增加而不断降低，20次干湿循环作用后岩样的应力波透射系数降低了约10%，说明干湿循环作用对应力波传播能力造成了显著影响。

Compression characteristics of filled jointed rock under dry-wet cycles

In order to explore the effects of dry-wet cycles on the compressive mechanical strength and deformation and failure characteristics of filled jointed rock, the artificial jointed rock samples with various fillings were prepared and then pre-treated by 0 (drying state), 1, 5, 10, 15, and 20 dry-wet cycles, which resulted in certain cumulative damage. On this basis, static uniaxial compression tests and dynamic impact tests were carried out on filled jointed rock samples, and in the process of dynamic impact tests, the impact failure characteristics of filled jointed rock were observed with the help of a high-speed camera. Research results show that with the increase in the number of dry-wet cycles, the static and dynamic compressive strengths of the filled jointed rock continue to decrease, and the decrease rates gradually becomes smaller. After 20 dry-wet cycles, the total deterioration degree of the static and dynamic compressive strength of the rock samples is between 20% and 30%. The dynamic compressive strength reduction law of rock samples conforms to the exponential function distribution through fitting. With the increase in the number of dry-wet cycles, the static failure mode gradually develops from splitting failure to shearing failure. In the process of dynamic impact, the degree of fragmentation of filled jointed rock and the degree of smashing and spattering of the filled joint group are aggravated, verifying that the dry-wet cycles will seriously affect the deformation and failure characteristics and dynamic impact resistance of filled jointed rock. In addition, the stress wave transmission coefficient of the rock sample decreases continuously with the increase in the number of dry-wet cycles, and after 20 dry-wet cycles, the coefficient decreases by about 10%. It can be seen that the dry-wet cycle has a significant impact on the stress wave propagation ability.