型钢再生混凝土界面黏结应力组成及其强度

Composition and Magnitude of Interface Bond Stress of Steel Reinforced Recycled Concrete

为研究型钢再生混凝土(SRRC)界面黏结应力组成与各部分黏结应力的大小,首先分析了型钢与再生混凝土的黏结应力组成,再根据17个型钢再生混凝土试件的推出试验,研究型钢再生混凝土界面黏结滑移的全过程;接着,通过理论分析并结合试验数据,求解了型钢再生混凝土界面的化学胶结应力和摩擦应力的大小,并推导了型钢屈服时的临界黏脱长度lcr计算公式;最后,对影响化学胶结应力和摩擦应力大小的因素进行了分析.研究结果表明:增大混凝土强度、配箍率与保护层厚度可提高摩擦应力,增大保护层厚度可提高摩擦应力与化学胶结应力.

In order to study the composition of bond stress for steel reinforced recycled concrete （SRRC）, composition of bond stress between steel and recycled aggregate concrete was analyzed first, and according to the push out test of 17 specimens, the whole process of SRRC interface bond slip was analyzed. Then, on the basis of the test and theoretical analysis, the level of chemical cementation stress and friction stress of SRRC interface were solved out, and the calculation formula of critical stick length lcr when steel yield was derived. Finally, factors influencing the level of chemicalcementation stress and friction stress were analyzed. Results show that increasing concrete strength, stirrup ratio and thickness of the protective layer can enlarge friction stress, and increasing the protective layer thickness can increase friction stress and chemical cementation stress.