二次受力下预应力钢绞线加固RC梁抗弯性能分析

Analysis of the Flexural Performance of Prestressed Strand-reinforced RC Beams under Secondary Stress

利用ABAQUS有限元软件分析二次受力影响下预应力钢绞线加固RC梁的抗弯性能,进一步研究初始加载程度、持载加固、卸载加固等影响因素对二次受力加固梁加固效果的影响。通过对已有试验进行建模分析,在验证数值模型准确性的基础上,设计了12根试件进行有限元参数分析,对比各参数在极限承载力、挠度、加固效果等方面的差异。研究结果表明:所建立的有限元模型可以合理预测预应力加固梁的抗弯性能。预应力钢绞线加固梁的极限承载力显著提高;当初始加载程度越大时,加固二次受力RC梁的极限承载力提高幅度越小,梁最大挠度的变化越小,二次受力对加固梁的整体性能影响越大;当构件受损严重时,宜采用卸载加固;选择受损较轻时对构件进行加固,以获得更好的加固效果。

ABAQUS finite element software is used to analyze the flexural performance of prestressed strand-reinforced RC beams under the influence of secondary forces,and further investigate the influence of the initial loading degree,load-holding reinforcement,unloading reinforcement,and other influencing factors on the reinforcement effect of secondary force-reinforced beams.By modeling and analyzing the existing tests,12 specimens were designed for finite element parameter analysis based on the verification of the accuracy of the numerical model,and compared the differences of each parameter in ultimate bearing capacity,deflection,and reinforcement effect.The results show that the developed finite element model can reasonably predict the flexural performance of prestressed reinforced beams.The ultimate load capacity of prestressed strand-reinforced beams is significantly increased;When the degree of initial loading is greater,the ultimate bearing capacity of the reinforced secondary stressed RC beam increases less,the maximum deflection of the beam changes less,and the influence of the secondary stress on the overall performance of the reinforced beam is greater;When the component is severely damaged,it is appropriate to use unloading reinforcement;When the damage is relatively light,the component is strengthened to obtain better reinforcement effect.