反复荷载下型钢再生混凝土组合柱粘结性能研究

为研究反复荷载下型钢再生混凝土组合柱粘结性能,对17个组合柱进行了拟静力试验。重点分析型钢翼缘应变分布特征,利用粘结应力计算公式获取型钢翼缘粘结应力大小及其分布规律。在此基础上,分析组合柱粘结破坏机理和位移荷载循环次数对其粘结应力的影响规律,并给出粘结应力退化率计算公式。研究结果表明:反复荷载作用下型钢再生混凝土组合柱粘结应力分布规律基本呈抛物线状;柱中部附近的粘结应力最大,柱上下端粘结应力分布复杂,需对这三个部位采取相应的措施以保证型钢与再生混凝土之间的粘结强度;位移循环荷载作用下粘结强度逐渐降低,出现粘结应力退化现象。研究结论可为型钢再生混凝土组合柱的抗震设计提供理论参考。

On the Bond Performance of Steel Reinforced Recycled Concrete Composite Column Subjected to Cyclic Loading

In order to study the bond performance of steel reinforced recycled concrete (SRRC) composite column,quasi-static experiment was carried out for 17 specimens.The strain distribution characteristics at steel flanges were selectively analyzed.The bond stress and its distribution at steel flanges were obtained by using bond stress calculation formula.Based on above results,the effect of bond failure mechanism of composite column and the number of cyclic loading cycle on the bond stress was analyzed.In addition,calculation formula of bond stress degradation rate is presented in this paper.Results show that bond stress distribution of steel reinforced recycled concrete composite column subjected to cyclic loading presents essentially parabolic shape.Bond stress at the column middle is the largest,and its distribution close to column top and bottom respectively is more complicated than that in other parts.Therefore,it is necessary to take corresponding measures to ensure the bond strength between steel and recycled concrete in above-mentioned three parts.Furthermore,the bond strength gradually decreases due to the cyclic loading,bond stress degradation phenomenon occurs.Above results may provide theoretical reference for the seismic design of steel reinforced recycled concrete composite column.