新型负泊松比高强钢筋与混凝土黏结性能的研究

Research on Bond Properties Between High-Strength Rebars of Negative Poisson Ratios and Concrete

针对我国自主研发的新型负泊松比高强高延性抗腐蚀性钢筋(NPR),采用中心拔出试验对NPR钢筋与混凝土间的黏结性能进行研究,观察试件的破坏形态,并分析钢筋类型(NPR钢筋、普通钢筋)、钢筋直径(8,18 mm)及黏结长度(5倍、7倍钢筋直径)对黏结强度及黏结滑移曲线的影响规律。试验结果表明:钢筋类型对破坏形态无明显影响,但对黏结滑移曲线的影响明显;其他条件相同时,NPR钢筋的黏结强度低于普通钢筋的黏结强度,且钢筋直径和黏结长度对两类钢筋与混凝土的黏结强度影响规律类似。

A new type of high-strength high-ductility corrosion-resistant rebars—Negative Poisson Ratio(NPR)has been developed independently in China.The bond properties of concrete with NPR rebars were studied by central pull-out tests.The failure modes of the specimens were observed,and the effects of rebar types(NPR rebars,ordinary rebars),rebar diameters(8,18 mm)and bond lengths(5 or 7 times the diameter of rebars)on the bond strength and bond slip curves were analyzed.The test results showed that the rebar type had no obvious effect on the failure mode,but it had obvious effect on the bond-slip curve.When other conditions were the same,the bond strength of NPR rebars was lower than that of ordinary rebars,and the influence laws of rebar diameters and bond length on the bond strength of two kinds of rebars were similar.