中外桥梁设计规范汽车荷载比较

Comparison of Vehicle load of Chinese and Foreign design code

桥梁结构在其寿命周期内所经历的最主要的活载是汽车荷载。近几十年经济的快速增长,使得交通状况发生了显著的变化,交通量、车辆载重量等均有显著的提高;国内外经济交流的愈趋频繁,对于桥梁设计者而言,有必要了解各国的规范。为此针对D60、BS5400、AASHTO、Eurocode等规范,通过车道划分、荷载标准值、折减系数、冲击系数、布载方式等方面对汽车荷载进行了分析比较。发现在跨径小于200 m时,BS5400规范的荷载值最高;在80m跨径以下D60规范的荷载值最低,Eurocode在80m到200 m跨径最小;当将荷载标准值外推至200 m跨径以上时,D60最高,Eurocode最低。

The most important variable action is vehicle load during the bridge's lifetime;however,the traffic volume and gross vehicle weight have remarkably changed in recent decades.Therefore we must pay attention to the traffic load,especially the international code following with more and more frequent international cooperation.This paper compared with different design codes,including D60,BS5400,AASHTO,Euro Code,in characterize value,reduction factor,impact factor and distribution mode.Basing on the particular comparison,it gives help and guidance to designers on understands and implication of traffic load.The results show when the span is less then 200m,BS5400 gives the highest characterize value.D60 gives the lowest when span is less than 80m while when span is great than 200m is the highest.Eurocode's value is lowest when the span is great than 80m.