设计了C30,C50和C80高性能混凝土深梁试件各3个,先针对其中的2个分别完成了在600℃和800℃高温下的火灾试验。通过对经历温度场、高温后试件的表面颜色、裂缝和完整性的观察,进行了普通混凝土和高性能混凝土深梁在无荷载状态下的火灾反应对比分析。之后对高温后的深梁进行了抗剪性能试验,在与常温下深梁受力性能对比分析的基础上,完成了高温后各深梁的挠度、承载力等抗剪性能的研究。最后通过试验与计算分析对比,建议了高性能混凝土深梁高温后抗剪承载力计算理论模式。
This paper engages in the fire-response test on HPC deep beams and shear-resistance behavior study after fire. The specimens are classified into 3 groups with the strength grade of C30, C50 and C80, respectively. Each group includes 3 specimens, 2 of which have been exposed to the elevated temperature of 600℃ and 800℃, respectively. During a fire under unstressed condition ,the temperature field is measured and concrete appearance is observed in detail after fire. Then the shear-resistance test on the simply supported deep beams are undertaken. Compared with those of in ambient temperature, the deep beams after fire are experimentally investigated in the respects of shear capacity, deflection and failure mode. Finally, the theoretical results are comparatively studied with the tested ones, and some equations are recommended to calculate the shear capacity of HPC deep beams after fire.