滚石冲击下新型组合棚洞结构的动力响应分析

Dynamic response analysis of a new composite shed-tunnel structure under the rockfall impact

棚洞结构是防止滚石灾害的有效措施之一,传统意义上的钢筋混凝土棚洞结构已经不能更好地解决这一问题。因此提出了一种以索网和钢桁架组合而成的新型组合棚洞结构的方法来阻拦滚石冲击。本结构中钢拱梁及格构柱为主要传力构件,主要承受拉力、压力、弯矩,而钢丝网及下部索网为主要的耗能构件,具有很大的变形能力,能够吸收滚石的冲击能。利用ANSYS/LS-DYNA有限元软件对该结构进行数值模拟,从加速度响应、能量耗散、应力传递三方面进行了动力分析,研究了滚石冲击对棚洞结构破坏的影响,为新型组合棚洞结构的设计提供了理论依据。

The shed-tunnel structure is one of the effective measures to prevent rolling stone disasters. The traditional reinforced concrete shed-tunnel structure does not have a better solution for this problem. Therefore,a new shed-tunnel structure that combined cable net with steel truss was proposed to resist rolling impact. In this structure,steel arched beams and latticed columns were the main force transmission components,which were mainly subjected to tension,pressure,and bending moments. The steel wire mesh and the lower cable net were the main component of energy consumption. They were able to absorb the impact of the rolling stones because they have large deformation ability.Numerical simulation of the structure by the finite element software ANSYS/LS-DYNA,the dynamic analysis was carried out from three aspects of acceleration response,energy dissipation,and stress transfer studied the effect of impact damage on shed-tunnel structure,it provides a theoretical basis for the design of the structure of the shed-tunnel structure.