避险车道末端消能轮胎布置方式对吸能特性的影响

避险车道末端的消能轮胎是对制动床上失控车辆进行强制减速消能的设施,消能轮胎的布置方式影响消能性能.为此,首先利用LS-Dyna软件建立8R22.5轮胎有限元模型并验证;其次对轮胎进行径向压缩试验和轴向压缩试验;最后使用整车模型与消能轮胎分别进行水平堆放和竖直堆放碰撞试验.从失控车辆速度、加速度以及碰撞接触力等方面分别对两种堆放布置方式进行对比研究.仿真结果表明:竖直堆放布置方式的消能轮胎的制动效率比水平堆放高,且更适合运用于场地条件受限制的避险车道末端;采用水平堆放布置方式的消能轮胎在最大吸能量以及对车辆及乘员的保护性能方面效果更好,场地条件允许情况下应优先采用水平堆放的布置方式.

Influence of stack way of Energy Absorbing Tire on Energy Absorption Feature at the End of Emergency Escape Ramps

Setting at the end of the emergency escape ramps, the energy absorbing tire is the facility for decelerating and absorbing the energy of out-of-control trucks compulsorily. The difference of its stack way influences its energy absorbing performance. At first, the FE model of 8R22.5 tires were build and validated by Ls-Dyna software. Then radial compression test and axial compression test were carried out. At last, truck model and the energy absorbing tire were used to carry out the horizontal stacking crash test and the vertical stacking crash test. After that, the two stacking arrangements were compared and studied in terms of the speed, acceleration and collision contact force of the out-of-control vehicle. The simulation results show that the braking efficiency of the energy dissipating tires in the vertical stacking arrangement is higher than that of the horizontal stacking, and it is more suitable for use at the end of the hazard lane where the site conditions are restricted; the energy dissipation tires in the horizontal stacking arrangement are at the maximum energy absorption and the effect on the protection of vehicles and occupants is better. If the site conditions permit, the horizontal stacking arrangement should be preferred.