高温后混杂纤维混凝土抗压强度

通过混杂纤维混凝土试块的高温后抗压试验,分析了温度、纤维类别和纤维体积率、混凝土基体强度等级对混凝土高温后抗压强度的影响。结果表明:随着经历温度的升高,混杂纤维混凝土高温后的抗压强度及高温后与常温下抗压强度比在400℃之后下降幅度较大;适宜掺量的钢纤维(1%纤维体积率)和聚丙烯纤维(0.1%纤维体积率)能较好的提高混杂纤维混凝土高温后的抗压强度。在试验研究的基础上,建立了考虑温度、钢纤维和聚丙烯纤维体积率共同影响的高温后混杂纤维混凝土抗压强度计算模型,为纤维混凝土结构的抗火设计及灾后处理提供了理论依据。

Compressive strength of hybrid fiber reinforced concrete after exposure to high temperature

Through the experiments on the compressive strength of hybrid fiber reinforced concrete(HFRC) after high temperature,the influence of temperature,fiber and concrete matrix strength grade on the compressive strength of concrete after high temperature was systematically analyzed.The results show that the falling-range of the compressive strength and compressive strength ratio after high temperature to room temperature of HFRC are less under 400℃ but apparently after 400℃.Steel fiber(1% fiber volume ratio) and polypropylene fiber(0.1% fiber volume ratio) can improve the compressive strength of concrete after high temperature in different degree.Based on the experiments,the calculation models of the cubic compressive strength and axial compressive strength of HFRC after high temperature are put forward respectively,in which the combined effects of temperature,steel fiber and polypropylene fiber on the models are considered.The results offer the method to fire-resistant design and the maintenance after fire for the HFRC structure.