柔性钢棚洞在落石冲击中的防护应用研究

Application of Flexible Steel Shed Hole in Falling Rock Prevention

随着落石防治的不断发展,柔性钢棚洞以透光性好、造价低等优势在落石防治中具有广阔的前景。但目前对柔性钢棚洞的研究在内部结构应力等方面仍有空白。以某公路隧道出口针对落石防治设置的柔性钢棚洞为例,研究落石下落的轨迹和最大冲击能量,利用数值模拟的方法,对设计的柔性钢棚洞的内部结构进行分析,最后辅以能量法对已有棚洞进行计算验证。结果表明,在落石对柔性钢棚洞的冲击中,柔性网中支撑绳吸收了大部分的能量,钢拱架受到的最大压力为拉力的2倍左右。

This article takes the prevention and control of rock fall at the exit of a highway tunnel at Jiuluzhai as an example to design a flexible steel shed-tunnel. In this paper, the basic dimensions of the shed are designed to limit the fall trajectory of the falling rock and the maximum impact energy by limiting the on-site topographic and geological conditions such as roads and tunnel heights at the exit, and then the size of the flexible steel is corrected by numerical simulation. The measures were followed by verification of the existing sheds using the newly proposed energy method, and finally the plan was established. The results show that in the impact of falling stone on the flexible steel shed-tunnel, the support rope in the flexible net absorbs most of the energy, and the maximum pressure on the steel arch is about twice of the tension.