摘要
梁底粘贴FRP(Fiber Reinforced Polymer)材料可以极大程度地提高梁的抗弯刚度,从而减小梁的变形。本文基于刚度法建立了FRP抗弯加固梁在不同阶段的刚度计算公式,利用变分法推导得到FRP抗弯加固梁单元刚度矩阵,建立了FRP加固梁单元,并基于有限单元法基本原理,利用数值软件建立FRP加固梁计算程序,对相关试验研究进行了分析。结果表明:本文所建FRP加固梁刚度计算方法在混凝土开裂后钢筋屈服前阶段计算结果偏大,通过计算FRP加固梁的屈服位移试验结果与本文计算结果的比值平均值,引入值为1.377的折减系数对这一阶段刚度进行了修正,修正后屈服挠度及极限挠度计算值误差分别在2 mm、8 mm以内,屈服弯矩及极限弯矩计算值平均误差分别为-3.0%、11.4%,同时,计算得到的各片梁荷载-位移曲线和试验所得荷载-位移曲线也能较好吻合。本文所建FRP加固梁单元计算结果精度较高,能够得到较好的分析结果,可为工程设计提供参考。
Paste FRP(Fiber Reinforced Polymer) material at the bottom of the beam can greatly improve the bending stiffness of the beam, thereby reducing the deformation of the beam. In this paper, the stiffness calculation formula of FRP flexurally reinforced beams at different stages is established by the stiffness method, and the stiffness matrix of the FRP flexurally reinforced beam element is derived by the variational method, and the FRP reinforced beam element is established. Based on the basic principle of the finite element method, The numerical software is used to establish the calculation program of FRP reinforced beams, and the related experimental researches are analyzed. The results show that the stiffness calculation method of FRP reinforced beams built in this paper is too large in the stage of reinforcement before yielding after concrete cracking. By calculating the average ratio of the yield displacement test results of FRP reinforced beams to the calculated results in this work, and introducing the reduction factor of 1.377 for calibration, the calculated errors of yield deflection and ultimate deflection are within 2 mm and 8 mm, respectively, and the average errors of yield bending moment and ultimate bending moment are-3.0% and 11.4%, respectively. At the same time, the calculated load-displacement curves of each beam are in good agreement with those of the test. In this paper, the calculation results of FRP reinforced beam elements are of high accuracy, and good analysis results can be obtained, which can provide reference for engineering design.
作者
许天才
马生强
淡丹辉
XU Tian-cai;MA Sheng-qiang;DAN Dan-hui(School of Architecture and Engineering,Xinjiang University,Urumchi 830049,China;School of Traffic and Transportation Engineering,Xinjiang University,Urumchi 830049,China;College of Civil Engineering,Tongji University,Shanghai 200092,China)
出处
《复合材料科学与工程》
CAS
北大核心
2022年第11期63-71,101,共10页
Composites Science and Engineering
基金
新疆维吾尔自治区自然科学基金资助项目(2020D01C027)
新疆大学博士科研启动基金项目(2019纵710003)。
关键词
FRP加固钢筋混凝土梁
抗弯
刚度矩阵
加固
FRP strengthened reinforced concrete beam
bending resistance
stiffness matrix
reinforcement
