新型耗能减震滚石棚洞作用机制研究

 传统滚石棚洞主要是通过结构顶部的砂砾石垫层来耗能抗冲击的，然而实践表明：砂砾石垫层材料不仅缓冲吸能效果有限，且自重荷载较大，建设成本偏高，不利于大面积推广应用。为此，提出一种新型耗能减震棚洞，通过在棚洞支座处增设耗能减震器，在最大限度降低棚洞自重的情况下增大防护结构的系统柔度，达到耗能减震的目的。通过构建非线性质量弹簧体系来模拟滚石冲击下棚洞结构的动力响应，并结合能量原理对新型棚洞的防滚石抗冲击机制进行分析，结果表明耗能减震棚洞能大幅度降低滚石的最大冲击力，并通过耗能减震器的变形来耗散冲击能，大幅度降低棚洞结构的建设成本。

RESEARCH ON CUSHIONING MECHANISM OF NEW-TYPED ENERGY DISSIPATIVE ROCK SHED

As a kind of serious hazard in mountains，rock-falls are hard to be treated accurately in active ways for their abruptness and randomness. Currently，the most popular method is to set cushion on shed tunnel to buffer the impact passively. However，the effect is not perfect as expected and the cost may be great if adopting thick cushion. Based on flexible retaining theory，a new type of shed tunnel is proposed，which can dissipate impact energy easily by installing shock absorber. Then by modeling the new structure as a mass spring system，the cushioning mechanism and protection effect of new structure are studied with energy theory. Finally，an example is given to check the presented approach. The result shows that the rock impact can be dissipated well by energy dissipative devices，and the maximum impact force on the new structure is smaller. More important，the investment of construction is reduced greatly.