外置金属阻尼器的新型自复位约束砌体墙抗震性能研究

Seismic Performance of a New Type of Self-centering Confined Masonry Wall with External Steel Dampers

研制了一种同时布置体内无黏结预应力筋和外置金属阻尼器的新型自复位约束砌体墙,通过拟静力试验研究了该自复位墙在低周反复荷载作用下的滞回性能,重点探明了预应力筋初始预应力、金属阻尼器屈服荷载大小对其耗能性能的影响,最后基于试验结果建立了数值分析模型.研究表明:该自复位约束砌体墙滞回曲线呈'旗形',在较大位移下未出现明显的损伤,且在加载及卸载过程中没有明显的强度和刚度退化;随着预应力筋初始预应力的增加,墙体的自复位性能增强,但其耗能能力会降低;随着金属阻尼器屈服荷载的增大,墙体的耗能能力增强,但会产生少量的残余变形;数值模拟结果与试验结果吻合较好,表明本文所提出的分析模型能较好地模拟该自复位约束砌体墙的力学行为.

A new type of self-centering confined masonry wall equipped with both unbounded tendons and external steel dampers was proposed. Its hysteresis behavior was studied through pseudo-static tests under cyclic loading, which focused on investigating the influence of the initial prestress of the tendon and the yield load of dampers on the energy dissipation capacity of the proposed wall. Based on the test results, a simplified numerical analysis model was established. It is showed that flag shape was a typical hysteresis curve of the wall. During the loading and unloading process, the wall specimen remained intact, and sig- nificant degradation of strength and stiffness was not observed. It is also found that the increase of the ini- tial prestress in tendons led to the enhancement of the self-centering ability but the reduction of the energy dissipation capacity of the wall on the other hand, when the yield force of steel dampers increased, the en- ergy dissipation capacity of the wall was improved, but some residual displacement occurred. Moreover, the numerical analysis results matched well with the test results, which indicate that the proposed numeri- cal models can well capture the mechanical behavior of the wall.