型钢轻骨料混凝土黏结滑移性能试验研究

Experimental study on bond behavior of steel reinforced lightweight concrete

通过推出试验,研究型钢轻骨料混凝土黏结滑移性能.采用正交试验设计,考虑了轻骨料混凝土强度、型钢埋置长度、保护层厚度、横向配箍率等因素对黏结滑移性能的影响.根据试验结果,统计回归了特征黏结强度和特征滑移值计算公式;提出了型钢轻骨料混凝土平均黏结应力-τ和加载端滑移SL的本构关系数学模型.研究结果表明:型钢埋置长度la与型钢截面高度d的比值和轻骨料混凝土强度对黏结强度影响较显著;型钢轻骨料混凝土相对于型钢普通混凝土有较小的黏结强度和较陡的荷载滑移下降段.

Push-out tests were conducted to study the bond behavior between section steel and lightweight concrete in steel reinforced lightweight concrete structures （SRLC）. Correlative factors were taken into account including lightweight concrete strength, embedded length, concrete cover, as well as stirrup ratio. According to the test results, the formulae of characteristic bond strength and characteristic slippage values are established by regression method, and the constitutive equations between average bond stress τ and loading end slip SL are presented. The results show that the ratio of embedded length Ia to the size of the encased section d and the strength of the lightweight concrete affect the bond capacity notably. The bond stress versus the slip curves of the lightweight concrete indicate a smaller bond strength and a steeper descending portion compared with the curves of normal concrete.