预应力 CFRP 布加固负载混凝土梁抗裂性能分析

为开展预应力碳纤维增强复合材料（CFRP）布加固混凝土受弯构件时对正截面裂缝影响的研究，设计制作了配筋率不同的2组共计8根试验梁。在承受40％极限荷载的基础上利用预应力CFRP 布对试验梁正截面进行加固，并完成其静载试验，获得混凝土受弯构件在前期加载和加固后的二次受力过程中弯曲段裂缝分布、裂缝宽度和高度的试验数据。在试验数据的基础上，通过理论分析，提出了与《混凝土结构设计规范》相协调的预应力 CFRP 布加固负载混凝土梁弯曲段裂缝平均间距和最大裂缝宽度的计算公式。研究结果表明：二次受力过程中，预应力 CFRP 布能有效抑制裂缝的开展，且随着预拉应力的增加，裂缝平均间距和裂缝宽度均减小。

Analysis of Anti-cracking Ability of Loaded Reinforced Concrete Beam Strengthened with Prestressed CFRP Sheet

In order to study the effect of reinforced concrete flexural members with prestressed carbon fiber reinforced polymer （CFRP） sheet on cross-section cracks ,two groups of eight test beams with different reinforcement ratios were designed .Based on bearing 40% ultimate load , the cross-section test beams were strengthened with prestressed CFRP sheet ,and the static load test was completed to obtain test data of bending crack distribution ,crack width and height of concrete flexural members in the early stage of loading and being strengthened after second loading .Based on the test data , through theoretical analysis ,calculation formulae of average crack spacing and maximum crack width of concrete beam strengthened with prestressed CFRP sheet were put forward ,which coordinated with Code f or Design of Concrete Structures .The study results show that in the process of second loading ,prestressed CFRP sheet can effectively suppress the development of crack ,and with increasing of the prestressed tensile stress , the average crack spacing and crack width decrease .