FRP片材加固钢筋混凝土梁挠度计算方法研究  

Study on Deflection Calculation Method Reinforced Concrete Beams Strengthened with FRP Sheets

作　　者：陈绪军[1] 

机构地区：[1]九江学院土木工程与城市建设学院,江西九江332005

出　　处：《铁道学报》2017年第11期103-107,共5页Journal of the China Railway Society

基　　金：江西省自然科学基金(20142BAB216004);江西省教育厅青年科学基金(GJJ13712)

摘　　要：采用纤维增强复合材料(FRP)片材加固钢筋混凝土梁可以大幅度提高其抗弯承载力,但其抗变形能力改善却并不显著。基于平截面假定,将FRP片材换算为受拉钢筋,推导换算后的截面有效高度增大系数表达式,通过有效惯性矩法分析得到FRP片材应变与实配受拉钢筋应变比值的变化规律。按照刚度解析法的思路,建立FRP片材加固的钢筋混凝土梁的抗弯挠度计算方法,得到的刚度计算公式在FRP加固量为零时可退化为GB50010—2010《混凝土结构设计规范》中普通钢筋混凝土受弯构件的抗弯刚度计算式。通过国内外相关试验梁数据验证表明,对于FRP加固的钢筋混凝土梁,采用本文计算方法得到的挠度计算值与试验值吻合较好,可供实际工程设计参考。The flexural capacity of reinforced concrete（RC）beam can be greatly improved when the beam is strengthened with fiber reinforced polymer（FRP）sheets,while the ability to resist deformation is not significantly increased.Based on the plane cross-section assumption,when the FRP sheets were transformed into tensile reinforcement,the expression of sectional effective height increment coefficient was proposed.Based on the analysis of effective inertia moment method,the variation of the strain ratio of the FRP sheet and the distribution of the strain ratio of the reinforcement was obtained.According to the idea of stiffness analytical method,the calculation method for the flexural deflection of FRP-strengthened RC beams simplified to the stiffness formula of unstrengthened beams was proposed.When the area of FRP sheets is zero,the stiffness formula of FRP-strengthened RC beams can be applied to RC flexural members given in the Code for design of concrete structures.The verification of the relevant test data at home and abroad proves that the calculated values of deflection for RC beams strengthened with FRP sheets,using the proposed formula,show a good agreement with the experimental values,which can be used as a reference for practical engineering design.

关 键 词：FRP 钢筋混凝土梁 加固 截面有效高度增大系数 挠度 

分 类 号：TU375[建筑科学—结构工程]