Analysis on characteristics of anti-impact and energy absorption of new type of composite folding column used in mining

The roadway anti-impact energy absorption support can effectively prevent the occurrence of rock burst, reduce the casualties and property losses caused by sudden disasters, and has achieved good application effect. The most important part is the energy absorption and anti-impact energy absorbing component. According to the principle of maximizing the plastic deformation area, a new type of energy absorption and anti-impact device with arc thin wall was presented to improve the shortcomings of the traditional device. In order to optimize the structure of the thin-wall energy absorption and anti-impact device, the properties of it was analyzed by using the method of finite element numerical simulation. At the same time, the energy absorption characteristics of the new type of composite corrugated column component for mining under different sidewall slopes and wall thicknesses are studied, so that the structure of the new type of composite corrugated column component for mining can reach the optimum. The results showed that: ①Under the same wall thickness, the peak bearing capacityF_max, the average crushing bearing capacityF_mean, the total energy absorptionE, and specific energy absorption ESA of the new device are higher than those of the traditional device, among which the average crushing bearing capacityF_mean has increased by 34.2%, total energy absorption has increased by nearly 33.6%, and specific energy absorption has increased by 127.4%. The new type of energy absorption device has obvious anti-impact performance advantages. ②With the decrease of the side wall slope, the peak crushing capacityF_max and the fluctuation coefficient of the bearing capacity decrease, the average crushing capacityF_mean increases, and the total energy absorptionEand the specific energy absorptionE_SA slightly increase. ③ As the thin-wall thickness of new device decreases, the crushing peak load, crushing average load, total energy absorption and specific energy absorption all decrease, while the load fluctuation coefficient decreases first and then increases. Through the analysis of the results, it is concluded that the structure of the new energy absorption device can meet the requirements of constant resistance and large deformation when the slope of side wall is 1.2 and the thickness is 7 mm, the component meets the requirements of constant resistance and large deformation; ④The fluctuation of bearing capacity curve can be further reduced by balancing the sidewall thickness and the contact friction coefficient between members and rigid plates.