Abstract:
Astering the dynamic response law of O-shaped support under impact load is the theoretical basis for designing support parameters of O-shaped suport in rock burst roadway. According to the change law of on-site support bearing capacity, the main factors affecting the impact load on the support are obtained. The impact energy generated by the impact ground pressure is partially transmitted to the O-support support bracket of the roadway in the form of impact stress waves, which causes deformation of the roadway support. Mastering the dynamic response of the roadway support under impact loading is the key to improving the impact resistance of the O-shaped support. The dynamic equation of the O-shaped support under the impact load is established, and the dynamic response of the roadway O-shaped support under the impact load is obtained. Studies have shown that by analyzing the characteristics of the impact ground load, it is found that the impact energy is attenuated rapidly when it is transmitted in the coal-rock medium. When the impact energy increases to a certain value, the force of impact load on the support increases rapidly.When the impact source reaches a certain value from the roadway, the impact load on the support is basically negligible; when the impact energy is increased to After a certain value, the impact of the impact load on the support increases rapidly. The dynamic equation of the O-shaped support under impact load is established, and the dynamic response of the O-shaped support under the impact load is obtained. The results show that the impact load will cause the O-shaped support to increase suddenly and generate vibration; The interaction between the O-shaped support and the surrounding rock under the action: the dynamic response of the O-shaped support under the impact load is affected by the surrounding rock coal and rock mass and the stiffness of the surrounding rock. The stronger the ability to displace and slow the internal force of the bracket, the better the impact resistance; the stiffness of the bracket is proportional to the dynamic response of the bracket. The higher the strength, the smaller the vibration frequency of the bracket. Therefore, the reasonable bracket stiffness is beneficial to improve the impact resistance of the bracket. The stiffness of the O-shaped supports has a greater impact on the dynamic response of the support. The higher the stiffness of the support, the lower the vibration frequency of the support. Therefore, a reasonable stiffness of the support is beneficial to improve the impact resistance of the support. As the impact load acts on the O-shaped support, the time increases, the bending deformation of the O-shaped support frame gradually decreases. It can be seen that factors such as the distance between the impact source and the roadway support, the properties of the surrounding rock medium of the roadway, the stiffness of the O-shaped support, and the duration of the impact load have a greater impact on the dynamic response of the O-shaped support. It was found that the bending deformation of the O-shaped support bracket gradually decreased with the increase of the impact load time. The research results are used to guide the optimization design of the O-shaped support parameters of a mine, and the dynamic response characteristics and regularity of the O-shaped support after the optimization of the supporting parameters are verified by the on-site support effect, so as to study the energy-absorbing and anti-shock O-shaped support in the future. Scientifically design the O-shaped support parameters to provide the basis.Based on this, the support parameters of the O-shaped support are optimized by changing the wall thickness and filling to increase the impact load time, increasing the supporting density and improving the rigidity and strength of the O-shaped support. Field practice shows that the optimized O-shaped support can withstand the impact ground pressure of 106 J energy, the damage of the support is obviously improved, and the impact resistance is significantly enhanced.