摘要
基于课题组前期对CFRP加固受火后预应力混凝土空心板的受力性能试验研究,提出了受火加固后的预应力混凝土空心板极限承载力的等效截面计算方法,同时针对影响受火后预应力混凝土空心板加固效果和破坏模式的参数进行了一系列分析。与试验结果对比表明,在考虑受火温度对材料进行强度折减后,提出的等效截面计算方法是可行的;CFRP加固量、CFRP覆盖率和板的前期受火时间对加固构件的承载力和破坏模式都有不同程度的影响。在实际加固工程中,应避免因加固量过大而发生剪切破坏;同时还应尽量增大加固时CFRP覆盖率,以充分利用CFRP材料的抗拉性能。
Based on the early experimental research on post-fire pre-stressed concrete hollow core slab strengthened with Carbon Fiber Reinforced Polymer(CFRP),this paper proposes an equivalent calculation method for ultimate bearing capacity of the strengthened PC hollow core slab,and carries on a series of analysis on different parameters influencing the performances of strengthened PC hollow core slabs.The predictions of ultimate bearing capacity of strengthened slabs were in close agreement with the test results after taking the strength reduction of material into consideration.Parametric analysis results show that the amount ratio and the coverage ratio of CFRP have different influence on the bearing capacity and failure modes of the strengthened members.It is necessary to choose the reasonable amount ratio to avoid the occurrence of shear failure due to excessive reinforcement.The high coverage ratio of CFRP can make full use of its tensile strength.
引文
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