隧道洞口防落石新型柔性棚洞结构抗冲击足尺试验与设计理论研究

In order to prevent rockfall hazards, full-scale test and design theory research on rockfall impact of a new type flexible rock-shed at tunnel face is about to be carried out, and a series of designing methods for the new type flexible rock-shed are about to be established, which can be applied to engineering practice. First, based on the rockfall characteristics, rockfall hazards at tunnel face are evaluated and rated, and the superiority of the new type flexible rock-shed on preventing rockfall hazards is clarified; every main component test and full-scale test on rockfall impact are carried out, and path of force transfer, energy consuming characteristics, failure mechanism are studied respectively. And then, the mechanical model of the new type flexible rock-shed is established; the calculation theory of structural energy dissipation based on energy method is studied; the influence of every key factor on the ultimate load capacity and energy dissipation is analyzed; the calculation theory of structural energy dissipation and design method of the new type flexible rock-shed based on energy method are established. At last, with the data and results of full-scale test, calculation theory, numerical simulations et al., actual parameters such as rockfall movement characteristics and indicators such as structural impact-resistant energy are all taken as the important input conditions during nonlinear analysis on rockfall impact of the new type flexible rock-shed; three-dimensional numerical simulations under complex rockfall impact and test verification can be achieved; the research accelerates the transformation of our country from applied country to study power of the new type flexible rock-shed.

为防治落石灾害，拟开展隧道洞口新型柔性棚洞结构抗落石冲击足尺试验和计算理论研究，建立一套能应用于工程实践的新型柔性棚洞结构设计方法。首先，基于落石特性，分级评估隧道洞口落石灾害，阐明新型被动柔性棚洞结构在防落石灾害的优越性；接着，开展新型柔性棚洞各主要构件、整体结构抗冲击足尺试验，研究传力路径、耗能特点、破坏机理。然后，建立新型被动柔性棚洞结构的力学模型，研究基于能量法的结构耗能计算原理，分析各关键因素对结构极限承载力、耗能的影响，建立基于能量法的隧道洞口防落石冲击新型柔性棚洞结构耗能计算原理和设计方法。最后，结合足尺试验、计算理论和数值仿真等数据和成果，将落石运动特性等实际参数和结构抗冲击能量等指标纳入落石冲击作用下新型柔性棚洞结构非线性计算分析时的重要输入条件，实现三维复杂动力冲击的数值仿真和试验验证，研发新型被动柔性棚洞结构设计软件，加速我国从柔性防护结构应用大国到研究强国的转变。

为防治落石灾害，拟开展隧道洞口新型柔性棚洞结构抗落石冲击足尺试验和计算理论研究，建立一套能应用于工程实践的新型柔性棚洞结构设计方法。首先，基于落石特性，分级评估隧道洞口落石灾害，阐明新型被动柔性棚洞结构在防落石灾害的优越性；接着，开展新型柔性棚洞各主要构件、整体结构抗冲击足尺试验，研究传力路径、耗能特点、破坏机理。然后，建立新型被动柔性棚洞结构的力学模型，研究基于能量法的结构耗能计算原理，分析各关键因素对结构极限承载力、耗能的影响，建立基于能量法的隧道洞口防落石冲击新型柔性棚洞结构耗能计算原理和设计方法。最后，结合足尺试验、计算理论和数值仿真等数据和成果，将落石运动特性等实际参数和结构抗冲击能量等指标纳入落石冲击作用下新型柔性棚洞结构非线性计算分析时的重要输入条件，实现三维复杂动力冲击的数值仿真和试验验证，研发新型被动柔性棚洞结构设计软件，加速我国从柔性防护结构应用大国到研究强国的转变。