不同限载等级对公路桥梁安全性的影响规律  

Influence Law of Different Weight Limit Levels on Highway Bridge Safety

作　　者：李松辉[1,2] 蒋含莞[2,3] 

机构地区：[1]山东科技大学山东省土木工程防灾减灾重点实验室,山东青岛266590 [2]交通运输部公路科学研究院旧桥检测与加固技术交通行业重点实验室,北京100088 [3]新墨西哥州立大学工学院,新墨西哥拉斯克鲁塞斯nm88001

出　　处：《中国公路学报》2016年第3期82-88,115,共8页China Journal of Highway and Transport

基　　金：山东省交通科技创新计划项目(2010Y01-2);旧桥检测与加固技术交通行业重点实验室开放基金项目(Jqkf2011-14)

摘　　要：应用结构可靠性理论,系统分析了钢筋混凝土中、小跨径简支梁桥在不同限载条件下的结构失效概率。首先,以规范建议的设计基准期内汽车荷载效应最大值分布为初始分布,提出了考虑不同桥梁限载等级因素的汽车荷载效应右截尾分布模型;进而,以不同的右截尾点取值模拟桥梁不同的限载等级,分析了不同右截尾点取值对桥梁失效概率的影响规律;最后,构造3种不同的汽车荷载效应超载分布模型,模拟桥梁不同的超载运营状态,进一步分析了右截尾点取值对超载桥梁失效概率的影响程度。结果表明:汽车荷载效应右截尾点取值对桥梁失效概率有不同程度的影响,随着右截尾点取值的减小,结构失效概率有所降低;桥梁超载程度越大,右截尾点取值对结构失效概率的影响越明显。Based on the structural reliability theory,the failure probabilities of simply-supported short and medium span reinforced concrete highways bridges were calculated under different bridge weight limit levels.Firstly,setting the maximum vehicular load effects during standardsuggested design reference period as the initial load distribution,the right truncated distribution models of vehicular load effects with the consideration of different bridge weight limit levels were proposed.Then taking different right truncation points to simulate bridge weight limit levels,the influence laws of right truncation points on structural failure probabilities of highway bridges were analyzed.Finally,three types of distribution models of overweight vehicular load effects were constructed to simulate different overload conditions on highway bridges,and the impacts degree of right truncation points values on structural failure probabilities were further analyzed for overload highway bridges.The results show that the failure probabilities of highway bridgesvary with the values of the right truncation points,and the structural failure probability will decrease with the reduction of values of the right truncation points.Meanwhile,given a certain value of the right truncation point,the higher overload will result in more obvious impacts on the structural failure probabilities of highway bridges.

关 键 词：桥梁工程 桥梁限载 可靠性分析 截尾分布 失效概率 

分 类 号：U447[建筑科学—桥梁与隧道工程]