中美公路桥梁设计规范的汽车荷载效应对比分析

Comparative Analysis of Chinese and American Highway Bridge Design Codes on Vehicle Load Effects

本文以不同标准跨径的单梁单车道简支T型梁为样本桥梁,将我国《公路桥涵设计通用规范》(JTG D60—2015)和美国AASHTO规范规定的汽车荷载分别作用在不同跨径的简支梁桥上,计算了汽车荷载标准值作用下以及分别考虑汽车荷载冲击作用、多车道横向折减和汽车荷载分项系数影响的样本桥梁的跨中弯矩值和支点剪力值,并进行对比分析。结果表明,对于样本桥梁,我国规范的汽车荷载标准值效应以及考虑汽车荷载冲击作用、多车道横向折减影响时的汽车荷载效应计算值均高于美国规范,考虑汽车荷载分项系数影响的汽车荷载效应计算值总体上小于美国规范。本研究可为我国今后修订汽车荷载标准提供一定的参考。

In this paper,single-beam single-lane simply supported T-beams with different standard spans were used as sample bridges,and the vehicle loads specified in the General Code for Design of Highway Bridges and Culverts(JTG D60—2015)and the American AASHTO Code were applied to different spans.On the simply supported beam bridge of the diameter,the mid-span moment value and the fulcrum shear force of the sample bridge under the influence of the vehicle load standard value and the influence of the vehicle load impact,the multi-lane lateral reduction and the vehicle load component coefficient were calculated respectively.Values were compared and analyzed.The results show that for the sample bridge,China's standard vehicle load standard value effect and the calculation of the vehicle load effect when considering the impact of the vehicle load and the multi-lane lateral reduction are higher than the US standard,and the car considering the car load component coefficient is considered.The calculated load effect is generally smaller than the US specification.This study can provide a certain reference for China's revision of vehicle load standards in the future.