大跨径桥梁伸缩缝处护栏结构的碰撞分析

为消除伸缩缝处的安全隐患,建立经碰撞试验验证的有限元仿真模型,对大跨径伸缩缝处事故形态进行分析,提出伸缩缝处的护栏结构并进行安全评价.对于这种组合式护栏的计算和试验,结果表明:仿真计算与碰撞试验结果一致,误差在15％以内,可作为分析评价伸缩缝处护栏安全防护性能的方法；时速100km/h、重1.5t的小客车和时速为65km/h、重22t的大货车碰撞伸缩缝护栏后,能够平稳驶出且恢复到正常行驶姿态,驶出角度分别为9°和0°；小客车车体X、Y、Z三方向加速度最大值分别为13g、17.8g和10.2g;护栏最大动态位移为200mm.伸缩缝护栏各项指标均满足评价标准要求,可有效消除伸缩缝处的安全隐患.

Impact Analysis of Barrier at Expansion Joint Location on Large Bridge

In order to eliminate potential safety problems at the expansion joints,finite element simulation models proved correct by impact test were set up to analyze accident performance at the location,and a barrier at expansion location was brought out and safety evaluation was done by finite element method.The results indicate that simulation results are consistent with the crash test,the error is 15%or less,and simulation can be a method to do safety evaluation analysis of barrier at expansion joints;1.5t car with 100km/h speed and 22t truck with 65km/h speed exit the barrier smoothly and are able to return to a normal run posture after impacting,and the exit angles of car is 9~°and that of truck is 0~°;the maximum acceleration of car in X,Y,Z direction is 13 g,17.8 g and 10.2 g respectively;the maximum dynamic displacement of barrier is 200 mm.The indexes of barrier at expansion joint location meet the evaluation criteria,and the barirer can effectively eliminate the security risks at the expansion joints.