重载预测模型及RC连续梁桥结构反应分析  

Heavy Vehicular Load Prediction Model and Their Effects on RC Continuous Girder Bridges

作　　者：刘浪[1,2] 王杰[2] 叶仲韬 LIU Lang;WANG Jie;YE Zhongtao(State Key Laboratory of Mountain Bridge&Tunnel Engineering,Chongqing Jiaotong Univ.,Chongqing 400074,China;School of Civil Engineering,Chongqing Jiaotong Univ.,Chongqing 400074,China;China Railway Bridge Science Research Institute Ltd.,Wuhan 430034,China)

机构地区：[1]重庆交通大学省部共建山区桥梁及隧道工程国家重点实验室,重庆400074 [2]重庆交通大学土木工程学院,重庆400074 [3]中铁大桥科学研究院有限公司,武汉430034

出　　处：《三峡大学学报（自然科学版）》2023年第3期68-74,共7页Journal of China Three Gorges University：Natural Sciences

基　　金：国家自然科学基金(51708069);重庆市基础研究与前沿探索项目(cstc2018jcyjA2535)。

摘　　要：为了解我国车辆交通量和车载水平的非平稳变化对公路桥梁承载力的影响,利用大量实测重载数据,分析了重载时间频度与荷载集度的非平稳特性,分别基于季节时间序列和RICE极值外推理论,建立了非平稳重载交通量预测模型和荷载极值模型,以实际重载交通流分布进行某实桥有限元模型加载,分析非平稳重载作用下桥梁的内力变化.研究结果表明:重载产生的跨中弯矩约为中国规范的1.21~1.55倍,美国规范的1.13~1.45倍.交通量增加后,跨中弯矩和支座负弯矩最大增幅分别为10%和22%,梁底混凝土的应力增大,最大增幅为14%.总体上,重载交通的非平稳增长使得主梁内力增加,但梁底混凝土应力大小未超出规范限值;重载在桥面的纵、横向空间分布特性对结构的内力影响较甚,在选取内力控制截面时应予以考虑.To study the impact of non-stationary growths of traffic volume and traffic class on the carrying capacity of highway bridges in China,mass SHM data were collected and the non-stationary characteristics on occurrences and levels were studied for heavy vehicular loads.Then,the traffic volume prediction model and extreme load extrapolation model were established for heavy loads taking account of non-stationary traffic growth.Furthermore,the established heavy load models were applied to the finite element model of a girder bridge according to the real distribution of heavy traffic loads recorded in the SHM data.The produced internal forces and stresses were calculated and analyzed.The results showed that the produced mid-span moments were 1.21~1.55 times that of the provided value in Chinese specification and 1.13~1.45 times that of AASHTO specification.Due to traffic volume growth,the produced mid-span moment and hogging moment increased maximally by 10% and 22%,respectively,and the concrete stress at the bottom of girders increased maximally by 14%.Generally,the non-stationary growth of heavy traffic loads led to greater internal forces in girders,and the maximum concrete stress was below the upper bound of code provision,but some tiny cracks or damage may occur at local places.In addition,the transverse and longitudinal distribution of heavy loads significantly affected the internal forces,which should be considered when selecting the dominant position.

关 键 词：车辆交通非平稳 重载 季节时间序列 RICE外推 桥梁承载力 

分 类 号：U441.2[建筑科学—桥梁与隧道工程]