二次受力粘钢加固PC箱梁力学性能研究  

Study on Mechanical Properties of PC Box Girder Strengthened with Bonded Steel under Secondary Stress Condition

作　　者：侯洋 张连振[1] 曹朋辉 HOU Yang;ZHANG Lian-zhen;CAO Peng-hui(School of Transportation Science and Engineering,Harbin Institute of Technology,Harbin Heilongjiang 150006,China;Beijing Xinqiao Technology Development Co.,Ltd.,Beijing 100089,China)

机构地区：[1]哈尔滨工业大学交通科学与工程学院,黑龙江哈尔滨150006 [2]北京新桥技术发展有限公司,北京100089

出　　处：《公路交通科技》2023年第10期79-86,共8页Journal of Highway and Transportation Research and Development

基　　金：陕西省自然科学基础研究计划项目(2020JQ-377)。

摘　　要：为解决国内PC箱梁桥腹板粘贴钢板抗剪加固后在正常使用状态下缺乏明确设计理论的问题,从PC箱梁腹板粘贴钢板对其抗弯刚度和斜裂缝宽度的影响为切入点,采用线性叠加原理、刚度分配理论研究了PC箱梁受弯构件腹板粘贴钢板加固后二次受力状况下加固构件的抗弯刚度与斜裂缝宽度计算方法,通过Abaqus仿真分析软件,建立了二次受力状况下PC箱梁桥的实体有限元模型,并将模拟结果与理论计算结果进行了比较。结果表明:当腹板斜裂缝宽度较大时,可以忽略腹板混凝土的抗弯刚度,理论公式计算结果与有限元模拟结果相近,抗弯刚度计算公式初步可用;针对斜裂缝宽度的计算,通过荷载-裂缝宽度影响曲线发现,当荷载小于某临界值时,荷载与斜裂缝宽度近似呈现出线性相关规律,此时可利用刚度分配理论对斜裂缝宽度进行计算,但当荷载增大到一定程度时,结构发生二次应力重分配裂缝发展出现明显拐点,刚度分配理论不再适用,此时建议采用较大的裂缝修正值。综上所述,当裂缝宽度在某限值之下时在荷载作用下钢板、混凝土、箍筋传力机制比较明确,线性叠加原理、刚度分配理论可以适用,一旦裂缝宽度超过限值,钢板对裂缝发展的抑制作用明显减弱,传力机制较为复杂,以上理论不再适用。In order to solve the problem of the lack of a clear design theory for the PC box girder bridge webs under normal use after bonding steel plates on the webs for shear reinforcement,starting from the influence of the PC box girder webs bonded steel plates on its flexural stiffness and the width of oblique cracks,using the linear superposition principle and stiffness distribution theory,the calculation methods of flexural stiffness and oblique crack width of reinforced PC box girder components under secondary stress condition after bonding steel plates to their webs are studied.The solid finite element model of the PC box girder bridge under the secondary stress condition is established by using Abaqus simulation analysis software,and the simulation result is compared with the theoretical calculation result.The result shows that(1)When the width of the oblique crack in the web is large,the flexural stiffness of the web concrete can be ignored.The calculation result of the theoretical formula is similar to the finite element simulation result,and the calculation formula of the flexural stiffness is preliminarily available.(2)For the calculation of the oblique crack width,it is found from the influence curve of load vs.crack width that the load and the oblique crack width approximately present a linear correlation rule when the load is less than a certain critical value.At this time,the stiffness distribution theory can be used to calculate the oblique crack width.However,when the load increases to a certain extent,secondary stress redistribution occurs in the structure,the crack development appears an obvious inflection point,and the stiffness distribution theory is no longer applicable,it is recommended to use a larger crack correction value at this time.In summary,when the crack width is below a certain limit,the force transmission mechanism of the steel plate,concrete and stirrup under the load is relatively clear,the linear superposition principle and the stiffness distribution theory can be applied.Once the cra

关 键 词：桥梁工程 钢板加固 理论分析 PC箱梁桥 抗弯刚度 斜裂缝 

分 类 号：U449.1[建筑科学—桥梁与隧道工程]