塑性铰区采用纤维增强混凝土剪力墙的变形性能研究

AN INVESTIGATION OF DEFORMATION BEHAVIOR OF THE SHEAR WALL WITH FIBER-REINFORCED CONCRETE IN PLASTIC HINGE REGION

为了提高高强混凝土剪力墙的抗震性能,在其潜在塑性铰区采用纤维增强混凝土代替高强混凝土,设计了4片剪跨比为2.1的剪力墙试件,进行了拟静力试验。通过改变纤维增强混凝土区高度、轴压比、纵筋数量、箍筋配箍特征值和水平分布筋数量,研究这种剪力墙的抗震性能。结果表明:这种剪力墙试件的抗损伤能力明显改善;纤维增强混凝土区高度对其变形能力有明显影响;开裂荷载和开裂位移显著提高。根据试验结果,分析了这种剪力墙试件的开裂位移、屈服位移和极限位移,给出了考虑剪切、弯曲变形影响的开裂位移、屈服位移和极限位移的计算公式,公式的预测值与试验值吻合较好。

In order to improve the seismic behavior of high-strength concrete shear walls, 4 shear wall specimens with fiber-reinforced concrete in the potential plastic region and shear span ratios of 2.1 were designed and the quasi-static tests were carried out. The seismic behavior was analyzed for various fiber-reinforced concrete regions, axial load ratios, longitudinal reinforcement, stirrup characteristic values and horizontal distributing bars. The results show that the damage tolerance of the shear wall was improved; the height of fiber reinforced concrete region influences the deformation capacity; the cracking load and the cracking displacement are improved. According to the results, the cracking displacement, yield displacement and ultimate displacement of the shear wall specimens are analyzed, and the crack displacement, yield displacement and ultimate displacement in the consideration of bending deformation and shear deformation are analyzed to derive a formula. The formula predictive value is in a good agreement with experimental results.