钢筋-地聚合物混凝土黏结性能研究

地聚合物混凝土是一种绿色低碳的新型建筑材料,因其耐高温、高早强、低反应热等特点,近十年受到了国际学术界和工程界的广泛关注。在与普通混凝土进行对比的基础上,通过钢筋拉拔试验研究了地聚物混凝土与钢筋的黏结性能,探讨了黏结长度等参数对黏结性能的影响。研究表明:与普通混凝土相比,地聚合物混凝土可以更好地传递钢筋的应力;传递相同的荷载,地聚合物混凝土比普通混凝土需要更小的混凝土保护层厚度和黏结长度;钢筋在地聚合物混凝土中的锚固性能具有加载速率敏感性,随着加载速率的提高,地聚合物混凝土与钢筋的黏结强度、破坏能耗均显著提高,但该敏感性随着黏结长度的增大而减弱。在分析试验数据基础上,提出了地聚合物混凝土与钢筋黏结强度的表达式,并提出了地聚合物混凝土结构设计建议。

Bond behavior between rebar and geopolymer concrete

Geopolymer concrete is a new type of low carbon building material which possesses features such as outstanding high-temperature resistance, high early-strength, low reaction heat, etc. Due to those advantages, geopolymer concrete has been extensively concerned by international academic and engineering world widely in last decade. In comparison to ordinary concrete, the bonding behavior between geopolymer concrete and rebar was studied through pull-out experiment. The influence of different parameters on the bond behavior of reinforcement in geopolymer concrete was discussed. Test data indicate that to transfer the same level of stress, the thickness of concrete cover and developing length of rebar in geopolymer concrete are much smaller than that in ordinary concrete; and the bond performance of rebar in geopolymer concrete is influenced by the loading rate. With increase of loading rate, an improvement in bond strength and energy consumption is achieved;however,the improvement becomes weak with the increase of developing length. Based on test data, empirical formulas were proposed to estimate the bond strength of rebar in geopolymer concrete. According to these formulas,some suggestions were recommended for the design of reinforced geopolymer concrete structures.