Research On Yield-damping Technology Of Bolt (Cable)

As a mature rock and soil anchoring technology,bolt(cable)support is widely used in slope engineering,underground structure engineering,foundation pit engineering,mine roadway support engineering and other fields.Its pressure damping performance is critical to the stability control of rock mass(surrounding rock).Based on the analysis of anchor(cable)support theory and the mechanism of pressure damping,this paper puts forward the key technology of bolt(cable)for pressure damping,and designs a new type of pressure damping device.Systematic experimental study on the pressure damping characteristics.The main conclusions are as follows:(1)According to the mechanism of bolt(cable)support,the theory and technical requirements of bolt(cable)support-surrounding rock coupling support are analyzed,and the key to realize the pressure-damping function of bolt(cable)support body is proposed.The technology is:the pressure point,the pressure distance and the ability to adapt to the shock load.(2)Based on the analysis of the existing pressure-reducing device performance(single bubble tube),a new type of pressure-reducing device was designed.It can be seen from the analysis of its action mechanism and influencing factors:The pressure point is related to the thickness of the outer ring.The maximum pressure is related to the height of the outer ring.The shock absorption function is related to the elastic material used inside.(3)Through the simulation test research on the new pressure relief device and the anchor(cable)support structure and the surrounding rock,the variation law of the pressure relief characteristics of the new pressure relief device is obtained.The results show:When the wall thickness of the confinement ring is constant,the pressure point is the same,and as the height of the confinement ring increases,the pressure distance increases;When a timing constraint height of the ring,the greater the wall thickness of the confinement rings,so that pressure point increases,so that the load pressure of the arrival point displacement gradually increased;The reliability and effectiveness of the new type of pressure-damping device coupling support are further verified.(4)Further bolt(cable)support structure and surrounding model by a different power stages(40%,60%and 80%of the pressure point),impact load(117.6J,235.2J and 352.8J)in three test.The results show:The new type of pressure-reducing device produces large elastic deformation in impact load energy,and increases with height,indicating that its device has strong ability to absorb shock loads and obvious shock absorption effect.(5)Traditional single bubble tubes can be seen characteristic test:Although a single bubble tube when a certain pressure so that the function,but the impact load,there is no significant elastic deformation.Therefore,the current single bubble tube used in the field does not have the damper function.