用无机胶粘贴CFRP布加固混凝土板火灾后受力性能

研发了600℃时强度不低于常温强度的无机胶,并用其粘贴CFRP布加固混凝土板。对4块已进行过火灾下耐火性能试验的加固板进行了火灾后受力性能试验。描述了用无机胶粘贴CFRP布加固混凝土板火灾后受力破坏过程,获得了加固板火灾后受弯承载力试验值和荷载-跨中位移变形曲线。进行了加固板火灾后受弯承载力分析。试验与分析表明,在CFRP布历经温度低于300℃时,用无机胶粘贴的CFRP布与混凝土板火灾后仍能共同工作,CFRP布的强度能够充分利用。在此基础上,提出了与试验结果吻合较好的承载力计算公式和刚度计算方法。

Mechanical performance of reinforced concrete slabs strengthened with CFRP sheets bonded with an inorganic adhesive after fire

An inorganic adhesive, whose strength at 600 ℃ is not lower than that at normal room temperature, was developed and used to bond CFRP sheets to strengthen concrete slabs. Experiments were carried out to investigate the mechanical properties of four strengthened slabs that had experienced fire. The flexural failure processes of the slabs were observed. Flexural carrying capacity of the slabs and the loading-displacement curves in the mid-span were obtained and analyzed. Results show that the strength of CFRP sheets bonded with the inorganic adhesive can be played fully when temperature that the sheets have experienced is below 300 ℃ in fire. Based on the results, the formula to calculate the flexural carrying capacity and the calculation method of the stiffness were presented. The calculation values are in good agreement with that of experiment results.