橡胶再生混凝土梁高温抗弯性能试验研究

Experimental study on bending performance of regeneration rubber concrete beam at high temperature

采用30%的再生骨料替代率作为基准配合比,0%、3%和5%的橡胶颗粒替代率配制混凝土进行高温下抗弯试验,得到梁高温下的截面温度分布场、跨中挠度和极限耐火时间,将普通混凝土梁与其进行对比分析,得到通过温度场理论计算橡胶颗粒再生混凝土梁耐火极限的理论分析方法。结果表明,所有类型混凝土梁的截面温度上升曲线具有相同趋势,即上升、平稳、急剧上升,并且温度梯度场和结构构件受热部位有关,距离越近温度梯度越大,距离越远温度梯度越小;混凝土的极限耐火时间随着荷载比的增大而减小,同普通混凝土一样,随着保护层厚度的增大,耐火性也增大。

The concrete was prepared using regeneration aggre- gate replacement rate of 30% as reference mix and the substitution rate of rubber particles of 0%, 3% and 5%, and the ben ding test at high temperature was made, the section temperature distribution, mid span deflection, ultimate fire-resistant time were obtained, and compared with those of ordinary concrete beam, and the theoretical calculation method of fire-resist ant limit of regeneration rubber concrete beam was obtained through theory calculation. The results showed that curves of section temperature rise of all types of concrete beams were similar,which was rise, steady, sharp rise. and the temperature gradient field was inversely correlated with structure component heated part; the fire-resistant limit decreased with increasing load ratio, and as ordinary concrete, fire-resistant performance increased with increasing thickness of protection layer.