Study on the support performance of anti-impacting and energy-absorbing concrete-filled steel tube arches in roadways

In response to the problem of lack of shrinkable pressure-allowing performance of steel pipe concrete arch in the current roadway support, an anti-impacting and energy-absorbing steel pipe concrete arch structure is designed from the perspective of energy-absorbing pressure-allowing. The combination model of the new steel pipe concrete arch and the surrounding rock was established by Abaqus, and the support effect and impact resistance of the new arch on the roadway were compared and analyzed under both static and dynamic loading conditions. The conclusions are as follows: ① Designing the wall thickness and size of the energy-absorbing member according to the reasonable yielding resistance characteristics. Energy-absorbing components are installed at the connection between the upper arch and the middle of the bottom arc to prevent excessive bending from causing instability. The sleeve shape is designed as a pleated shape based on the U-shaped steel arch clamp structure, which achieves compression yield through friction with the arch; ② Under the vertical and lateral impact, the displacement of the optimized arch support tunnel at each point is reduced, which reduces the sinking of the top arc section of the arch and the up-arch of the bottom arc section, and the support effect is stronger; ③ Under static loads, after the arch contacts the energy-absorbing component, the plastic strain at each point of the arch no longer increases, and the energy-absorbing component replaces the arch to deform. After being subjected to dynamic loads, the energy-absorbing component can respond quickly, while the corners of the arch bend and deform, and the remaining parts have not undergone significant deformation. After the energy-absorbing component is crushed, the overall plastic strain of the arch starts to increase, and finally the equivalent plastic strain at each point of the arch is reduced by 10%−50% and 13%−78% under vertical and lateral impacts, respectively, after optimization.