预应力碳纤维板在梁桥加固工程中的应用研究

Research on the application of carbon fiber plate in reinforcement engineering of concrete beam bridge

为探究碳纤维板加固传统混凝土梁桥之后结构的抗弯承载性能变化特征,本文以试验梁为研究对象,通过理论力学手段分析了采用直接粘贴法及预应力碳纤维板加固法加固结构前后,混凝土结构抗弯承载力的变化情况,总结了两种碳纤维板加固法加固试验梁后的结构抗弯承载力;结合数值模拟分析,探究了试验梁加固前后裂缝发展趋势、跨中挠度及受拉钢筋应变趋势变化情况。研究结果表明:碳纤维板能够有效增加结构的承载性能,其中,粘贴法碳纤维板加固之后的梁桥抗弯承载能力提升了63.6%;采用预应力碳纤维板加固之后的梁桥抗弯承载能力提升了109.1%。加固后的桥梁结构抗弯承载力相较于未加固前的结构承载能力增加了122.66%,修正后的实际工程理论解析与试验梁数值模拟结果差异仅为2.3%,工程实践理论解析与试验梁数值模拟结果具有一致性。

In order to explore the change characteristics of flexural bearing capacity of traditional concrete girder bridges strengthened by carbon fiber plates,theoretical analysis and numerical simulation methods are used to conduct comparative research and analysis.Taking test beams as research objects,theoretical mechanics methods are used to analyze the changes in flexural bearing capacity of concrete structures before and after strengthening the structures by direct adhesion method and prestressed carbon fiber plates.The flexural capacity of test beams strengthened by two methods of carbon fiber plate reinforcement is summarized.Combined with numerical simulation analysis,the crack development trend,mid-span deflection and strain trend change of tensile reinforcement before and after the reinforcement of test beams are investigated.The results show that carbon fiber plate can effectively increase the bearing capacity of the structure,among which,the flexural bearing capacity of the beam bridge strengthened with carbon fiber plate is increased by 63.6%.The flexural capacity of the beam bridge reinforced with prestressed carbon fiber plates increased by 109.1%.the flexural capacity of the reinforced bridge structure increases by 122.66% compared with that before the reinforcement.The difference between the theoretical analysis of the modified practical engineering and the numerical simulation results of the test beam is only 2.3%,and the theoretical analysis of the engineering practice is consistent with the numerical simulation results of the test beam.