不同引板形式延伸桥面板无缝桥受力性能分析  

Analysis on the Mechanical Performance of Deck-extension Jointless Bridge with Various Types of Approach Slabs

作　　者：马熙伦 杨傲雄 罗小烨 马伟 MA Xilun;YANG Aoxiong;LUO Xiaoye;MA Wei(School of Civil and Hydraulic Engineering,Ningxia University,Yinchuan,Ningxia 750021,China;School of Resource Engineering,Longyan University,Longyan,Fujian 364012,China)

机构地区：[1]宁夏大学土木与水利工程学院,宁夏银川750021 [2]龙岩学院资源工程学院,福建龙岩364012

出　　处：《公路工程》2025年第1期1-7,97,共8页Highway Engineering

基　　金：宁夏自然科学基金项目(2023AAC03131);国家自然科学基金地区项目(52368025);龙岩学院博士启动项目(0000290612)。

摘　　要：无缝桥引板与主梁联结,传递主梁伸缩变形,不同引板形式会对无缝桥受力性能产生影响。为研究不同引板形式对延伸桥面板无缝桥受力性能的影响,以宁夏首座3×30 m连续梁延伸桥面板无缝桥为背景,分别建立未考虑引板和考虑不同引板形式的无缝桥有限元模型,分析了温度影响下不同引板形式对无缝桥主梁受力、伸缩变形及动力特性等影响规律。研究表明:桥梁整体升温至34℃和降温至-10℃的情况下,引板主要影响无缝桥边跨处的主梁受力,使边跨的弯矩减小;降温时,主梁和引板连接处的拉应力增大,拉应力增大超过30%,引板破坏主要表现为拉裂;引板坡度变化对主梁弯矩影响较小,但对主梁拉应力有影响,随着引板坡度增加,拉应力明显减少;延伸桥面板无缝桥的伸缩量,与现行规范计算值相比,明显减小,在缺乏更为精确的计算方法前,可在现行规范计算值的基础上考虑0.73~0.91的修正系数;引板的坡度变化对整个桥梁的频率和振型基本无影响。Approach slabs of jointless bridges are connected with girders to transmit the expansion and contraction deformations of the girders.Various types of approach slabs will affect the mechanical performance of jointless bridges.To investigate the effect of various types of approach slabs on the mechanical performance of deck-extension jointless bridges,taking the first 3×30 m continuous beam extended bridge deck seamless bridge in Ningxia as the background,finite element models of seamless bridges were established without considering approach slabs and considering different approach slabs forms.The effects of different approach slabs forms on the stress,expansion deformation,and dynamic characteristics of the main beam of the seamless bridge under temperature were analyzed.The results indicate that when bridge overall heated to 34℃and cooled to-10℃the approach slabs primarily affect the girder's stress at side spans of the jointless bridge,resulting in a reduction of bending moments at side spans.Tensile stress at the connection between the girder and the approach slabs increases significantly,exceeding 30%as the temperature decreases,with the failure of the approach slabs mainly manifesting as tensile crack.The influence of the approach slabs with varying slopes on the girder's bending moments is relatively minor,but it does have an impact on tensile stress,which notably decreases with an increase in the slope of the approach slabs.The calculated expansion and contraction deformations of deck-extension jointlessbridgesare significantly smaller compared to the values calculated by existing standard.Until a more precise calculation method is available,a correction factor of 0.73~0.91 can be considered based on the existing standard calculation values.The change in slope of the approach slabs has little effect on the frequency and vibration mode of the entire bridge.

关 键 词：延伸桥面板桥 引板坡度 受力性能 伸缩变形 修正系数 

分 类 号：U443.31[建筑科学—桥梁与隧道工程]