为研究高温后不同冷却方式下混凝土-钢筋的黏结滑移性能，对39个高温后混凝土试件进行了中心拉拔试验，并完成了自然冷却方式下试件的劈裂抗拉强度试验，分析了温度和冷却方式对试件峰值黏结应力和峰值滑移的影响，建立了不同冷却方式下峰值黏结应力、峰值滑移与温度的关系式，提出了考虑初始温度损伤的黏结滑移全曲线方程，并基于黏结强度理论模型计算了自然冷却方式下的黏结强度理论值。结果表明：随着温度的升高，峰值黏结应力线性下降，500 ℃时黏结强度损失达80.5%，峰值滑移随温度升高呈现先减小后增大的趋势，不同冷却方式对峰值黏结应力和峰值滑移的影响不明显；考虑损伤的理论黏结滑移全曲线与试验曲线拟合度较好；采用理论模型计算的黏结强度与试验值较吻合。

In order to study the bond-slip performance between concrete and steel rebar after different cooling ways, 39 pull-out tests of reinforced concrete specimens after exposure to high temperature and the splitting tensile strength tests of concrete under natural cooling way were carried out. The effect of high temperature and different cooling ways on peak bond stress and peak slip are discussed. The calculation equations between peak bond stress, peak slip and temperatures are established, and the full curve equation of bond slip considering initial temperature damage is also proposed. Based on the theoretical model, the theoretical bond strength after natural cooling is calculated. The results show that: with the increase of temperature, the peak bond stress decreases linearly, the maximum reduction for 500℃ reaches to 80.5%, and the peak slip first decreases and then increases after the same cooling way, and the cooling way has little effect on these parameters; the theoretical damage bond slip curves is consistent with the test curves; the bond strength calculated by the theoretical model well agree with the test value.

TU312

国家自然科学基金（51768004）