钢筋混凝土空心柱抗震性能的试验研究

在我国装配式板柱体系房屋中比较广泛采用了钢筋混凝土空心柱,它的抗震性能如何却仍足有待研究解决的重要问题。本文讨论了钢筋混凝土空心柱在周期反复荷载作用下的抗震性能;研究了空心率、轴压比以及箍筋形式和纵向钢筋配置方式等因素对滞回特性和延性的影响,并与实心柱进行了对比。共进行了三十根试件的试验研究。试验结果表明,由于空心率的增加,构件的延性降低,变形性能明显变差。试验还表明,伸入节点区钢筋的粘结滑移对构件的变形及滞回特性有明显的影响。文中利用空心率影响系数修正名义混凝土压区高度系数来反映空心率对构件延性比和塑性转动能力的影响,从而得出了与实心截面柱相类似的变化规律。文中还根据对钢筋混凝土空心柱变形的全过程分析确定极限承载能力,并与实验结果进行了比较,表明两者符合较好。

The Experimental Investigation of the Seismic Resistance Behaviour of Reinforced Concrete Hollow Core Columns

Reinforced concrete hollow core columns have been used in the slab-column system structures in our country.The important problem of seismic resistance behaviour of such structure is still need to be studied. In this paper, the behaviour of reinforced concrete hollow core columns under cyclic loading is discussed.The influences of the percentage of hollow core,the ratio between axial forces and compression strength of concrete as well as the arrangement of stirrups and longitudinal reinforcement on the hysteretic characteristics and ductility of hollow core columns are investigated and compared with that of solid columns. Thirty specimens were worked out. The tests show that the ductility of columns decreases with the increasing of the hollow core area and the deformation behaviour becomes worse apparently. The tests also show that the bond slippage of reinforcements in the joint area affects the deflection and the hysteresis loops of the specimens significantly. In order to reflect the effect of hollow core rate on the ductility and plastic rotation capacity of the colunm, a coefficient considering the effect of hollow core rate is introduced to modify the coefficient of nominal depth of compression zone of concrete and a rule similar to that of solid column is obtained.In addition, by analyzing the complete load-deflection curve of hollow core columns, the ultimate load capacity is acquired,it is in good agreement with the experimental results.