Dynamic response experiment of surrounding rocks under influence of mine earthquake and mined-out area

To find about the dynamic response patterns of surrounding rock in which mine earthquake and mined-out area exist side by side, and obtain the mechanism leading to disasters under the coupled action of the two, we conducted a percussion test on circular plates having holes and established a model for it. The model test shows that negative acceleration is monitored in the surrounding rock, that the negative acceleration is unrelated with the gravity effect, and that tangential acceleration is also monitored. With the increase of the diameter of the hole, the tangential acceleration around the circular plate exponentially increased. According to the results of the experiment, we arrived at the mechanisms leading to disasters under the coupled action of mine earthquake and mined-out area, including the intensified subsidence and caving in overburden of the goaf, the formation of the horizontal acceleration in shared rock pillars of mined-out area pointing to the source location, the formation of the horizontal shear acceleration in the upper part of the surrounding rock where mine earthquake and mined-out area exist side by side. Comprehensive analysis of the test data, size effect of mined-out area and zoom effect of mine vibration load, do not affect the test results.