矿山开采、交通隧道等扰动区域内的实际深部裂隙岩体，在施工过程中受到动态扰动发生破坏，或产生损伤进而降低了作为围岩的承载荷载能力。通过应用损伤力学的方法对节理、裂隙岩体进行分析，可以将其视为一种带有预先存在宏观损伤的材料，构建裂隙岩体应力-应变关系模型，探究裂隙岩体动力损伤与力学性能劣化特性。因此本文通过研究含裂隙花岗岩在受循环冲击荷载破坏过程中的力学性能变化，探究裂隙对岩石动力学性能的影响规律；并对含裂隙花岗岩受循环冲击损伤的后的静态力学性能及破坏模式进行研究，探究受损裂隙岩石的强度劣化规律。主要研究内容与结果如下：

（1）利用霍普金森系统（SHPB）对含裂隙花岗岩试件进行等幅循环冲击试验和变幅循环冲击试验，依据试验结果发现，试样的动态抗压强度与裂隙倾角和循环冲击次数均有一定的相关性。在等幅冲击情况下，随着裂隙倾角的增加，试样的峰值应力呈先下降后增加趋势，随着冲击次数的增加，试样的抗压强度降低，峰值应变增加，动态弹性模量降低；在变幅冲击情况下，试样峰值应力和峰值应变与冲击气压呈正比，动态弹性模量与冲击气压呈反比。

（2）通过调整循环冲击次数，制备了受到不同程度动态扰动损伤的含裂隙花岗岩试件，基于受扰动前后试样的波速变化定义了损伤变量，发现试样在受到动态冲击后波速均有一定程度的降低，损伤变量会有所增加，变化的幅度与裂隙倾角和循环冲击次数具有一定的相关性。

（3）利用单轴试验机对受到不同程度动态扰动损伤的含裂隙花岗岩试件进行静力学试验，发现试件强度与峰值应变随裂隙倾角增大呈V形变化趋势，弹性模量与循环冲击次数和裂隙倾角的相关性较弱。试样的破坏模式主要是剪切和张拉破坏，扰动次数和裂隙角度主要影响试件破碎的块度，对于破坏模式的影响较小。

（4）结合动力学试验与静力学试验的力学参数和破坏模式结果分析得出，含裂隙花岗岩试样的裂隙倾角为45°时，试样受动载作用时的抵抗变形能力最弱，动态强度最低；在单轴压缩时，破碎块度较小，可以认为此角度为易起裂倾角。

（5）结合动力学试验结果，基于Weibull统计损伤本构模型，通过引入初始裂隙表征系数k_d ，推导出考虑含初始裂隙的花岗岩损伤演化方程和动态损伤本构模型。模型得出的动态应力-应变曲线与试验实测曲线在峰值前的阶段具备良好的吻合度。并讨论了循环冲击对裂隙花岗岩损伤演化的规律。

The actual deep fractured rock mass in disturbed areas such as mining and traffic tunnels is destroyed or damaged by dynamic disturbance during the construction process, thereby reducing the load-bearing capacity of the surrounding rock. By applying the method of damage mechanics to analyze the joints and fractured rock mass, it can be regarded as a material with pre-existing macroscopic damage, and a stress-strain relationship model of the fractured rock mass is constructed to explore the dynamic damage and mechanical property degradation characteristics of the fractured rock mass. Therefore, this paper studies the changes in the mechanical properties of fractured granite during the destruction process of cyclic impact loads to explore the influence of fractures on the dynamic properties of rocks; and studies the static mechanical properties and failure modes of fractured granite after cyclic impact damage to explore the strength degradation law of damaged fractured rocks. The main research contents and results are as follows:

(1) The Hopkinson system (SHPB) was used to conduct constant amplitude cyclic impact tests and variable amplitude cyclic impact tests on cracked granite specimens. According to the test results, it was found that the dynamic compressive strength of the specimens was consistent with the crack inclination angle and the number of cyclic impacts. There is a certain relevance. Under the condition of equal amplitude impact, with the increase of crack inclination angle, the peak stress of the sample first decreases and then increases. With the increase of the number of impacts, the compressive strength of the sample decreases, the peak strain increases, and the dynamic elastic modulus decreases. Under the condition of variable amplitude impact, the peak stress and peak strain of the sample are proportional to the impact pressure, and the dynamic elastic modulus is inversely proportional to the impact pressure.

(2) By adjusting the number of cyclic impacts, cracked granite specimens with different degrees of dynamic disturbance damage were prepared. The damage variable was defined based on the change of wave velocity of the specimen before and after the disturbance. It was found that the wave velocity of the specimen decreased to a certain extent after the dynamic impact, and the damage variable increased. The amplitude of the change had a certain correlation with the crack inclination angle and the number of cyclic impacts.

(3) Static tests were carried out on cracked granite specimens with different degrees of dynamic disturbance damage using a uniaxial testing machine. It was found that the strength and peak strain of the specimens showed a V-shaped change trend with the increase of crack inclination angle, and the elastic modulus had a weak correlation with the number of cyclic impacts and crack inclination angle. The failure modes of the specimens are mainly shear and tensile failures. The number of disturbances and the crack angle mainly affect the size of the specimens, and have little effect on the failure mode.

(4) Combining the mechanical parameters and failure mode results of the dynamic test and the static test, it is concluded that when the crack inclination angle of the cracked granite specimen is 45°, the specimen has the weakest deformation resistance under dynamic load and the lowest dynamic strength; under uniaxial compression, the broken block size is small, and this angle can be considered as an easy cracking inclination angle.

(5) Combining the dynamic test results, based on the Weibull statistical damage constitutive model, by introducing the initial crack characterization coefficient , the damage evolution equation and dynamic damage constitutive model of granite with initial cracks are derived. The dynamic stress-strain curve obtained by the model is in good agreement with the experimental measured curve in the stage before the peak. The law of damage evolution of cracked granite under cyclic impact is also discussed.