Study On The Feature Of Impact Vibration And Dynamic Response Of Caused By Roof Caving

Cave-in mine tremor conversion the potential energy of upper rock to vibration energy propagation in rock,and makes the fractured width of cave-in mine tremor expanded rapidly. The study about the impact vibration induced by falling rock is important to forecast the harm of mine earthquake.Firstly,this paper explore the conversion of energy based on the conservation of energy. In the process of falling rock impact,the potential energy of falling rock consume to the vibration energy of bottom rock, thermal energy cased by shock rock,elastic strain energy, surface energy of cranny, plastic potential energy, radiant energy etc. This paper summarizes the current research situation of blasting vibration and collapse vibration, then explore the influence of force on the contact area.The experiment of rock impact indoor with UBOX-20016 blasting vibration recording system test the vibration cased by falling rock impact, explore the relation between vibration velocity, vibration frequency and falling height, quality of the rock. This paper analyze the influence of contact area, established the vibration model of the falling rock impact initially. At the base of indoor experiment, carry out the underground test of falling rocks vibration. Regulating the layout scheme of sensors according to the underground site, the test of Vibration signal adopt IDTS-3850 blasting vibration. Underground test summarize the attenuation law of the impact vibration about the gypsum mine.According to the rules of explosion safety(GB6722-2003), make out the first-step predict of safe range about the impact vibration based on the aboratory test. Vibration velocity is large near the point of impact, and attenuate rapidly to 30 cm/s that is safety vibration velocity in a relatively short distance.