Study on the impact of vehicle‑induced vibration on the flexural behavior of UHPC joints in widened bridges  

作　　者：Jun Yang Jingchen Leng Jianting Zhou Rui Chen Kun Yu Zhimei Jiang Yang Zou Zhongya Zhang Jiang Du 

机构地区：[1]State Key Laboratory of Mountain Bridge and Tunnel Engineering,Chongqing Jiaotong University,Chongqing 400074,China [2]School of Civil Engineering,Chongqing Jiaotong University,Chongqing 400074,China

出　　处：《Urban Lifeline》2024年第1期277-289,共13页城市生命线(英文)

基　　金：support from the Natural Science Foundation of China(Grant No.52278147,52208302,52278293,U20A20314);the Science and Technology Research Program of Chongqing Municipal Education Commission(KJZD-M202300706);the Natural Science Foundation of Chongqing,China(CSTB2023NSCQ-MSX0019);the Chongqing Science and Technology Project(CSTB2022TIAD-KPX0205);the China Railway Major Project(2022-ZD-11);the Guangxi key research and development plan project(Grant No.GuikeAB22036007);the Research and Innovation Program for Graduate Students in Chongqing(Grant Nos.CYB23245).

摘　　要：Bridge widening involves phased construction of adjacent structures to maintain uninterrupted traffic flow.This process exposes freshly placed longitudinal joints between staged deck constructions to vehicle-induced vibrations,potentially compromising their mechanical integrity.This study investigates the flexural behavior of ultra-highperformance concrete(UHPC)longitudinal joints under such vibrations through model tests.To simulate actual site conditions,we developed a novel vibration test setup that replicates the dynamic environment experienced by these joints during construction.Micro-and meso-scale tests were conducted to examine the flexural behavior of longitudinal joints following vibration exposure.Results revealed that vibration amplitude significantly influences fiber orientation and flexural strength of ultra-high-performance concrete(UHPC)wet joint specimens.Low-amplitude vibrations(3 Hz at 1 mm and 3 mm)enhanced fiber orientation,increasing flexural strength by 11.5%to 19.8%and ultimate load capacity by 17%compared to non-vibrated specimens.Conversely,high-amplitude vibrations(3 Hz at 5 mm)adversely affected fiber orientation,decreasing flexural strength by 23.9%and ultimate load capacity by 19%relative to non-vibrated specimens.

关 键 词：Longitudinal joint Vehicle-induced vibration Ultra-high-performance concrete Flexural behavior Microstructural properties 

分 类 号：TU5[建筑科学—建筑技术科学]