隧道入口处混凝土护栏设计及安全性能分析

Design of Concrete Barrier at Tunnel Entrance and Analysis on Safety Performance

目前隧道入口处设置波形梁护栏的处理方式易导致失控车辆直接正面碰撞隧道壁和检修道,对车辆安全极为不利。本文设计出一种有利于避免失控车辆与隧道壁或检修道发生正面碰撞的混凝土护栏,护栏长度36 m,高度由1 m渐变至1.6 m,采用D81细则规定的F型坡面,检修道切角尺寸1 m×0.14 m,检修道和隧道壁均位于护栏后方。采用计算机仿真分析方法对隧道入口处的混凝土护栏进行安全性能进行了分析验证。分析结果表明:车辆碰撞护栏后没有穿越、翻越和骑跨护栏;护栏构件及其脱离件没有侵入车辆乘员舱;车辆碰撞后没有翻车,运行轮迹满足导向驶出框要求,车辆行驶至隧道壁以及检修道位置时向前方顺利导出并驶入隧道内,护栏安全性能满足评价标准要求。

At present the design of W-beam barriers settled at tunnel entrance easily leads to runaway vehicles frontally impacting with tunnel wall and maintenance roadway,which is supremely harmful to vehicles safety. A kind of concrete barrier which is favorable to avoid the frontal impact of runaway vehicle with tunnel wall or maintenance roadway is designed. The length of this barrier is 36 m,the height is from 1m to 1. 6 m and the slope surface is F type prescribed in D81 specification. The dimensions of cutting corner in maintenance roadway are 1 m × 0. 14 m. The tunnel wall and maintenance roadway are both behind the barrier.The analysis and verification of safety performance of the concrete barrier at tunnel entrance are conducted by the method of computer simulation. The analysis result shows that（ 1） the vehicles did not penetrate,climb or override the barrier;（ 2） the components and detached elements of the barrier did not intrude into the occupant compartment;（ 3） the vehicles did not overturn after collision,the running tracks meet the requirements of exit box,the vehicles run forward smoothly and entered into the tunnel at the position of tunnel wall and maintenance roadway,so the performance of this concrete barrier can meet the safety requirements.