钢纤维高强预应力混凝土扁梁框架拟动力试验研究

Pseudo-dynamic test of fiber-reinforced high-strength prestressed concrete wide-beam frame

采用MTS伺服加载系统对钢纤维高强无粘结预应力混凝土扁梁框架结构进行拟动力地震反应试验研究。试验采用经过调幅的具有不同地震加速度峰值的ElCentro地震波作为激励进行加载,对两榀钢纤维高强预应力混凝土扁梁框架和一榀用来对比的普通高强混凝土扁梁框架进行拟动力试验,对结构在地震作用下的加速度反应、位移反应、滞回性能、刚度和耗能进行研究,分析钢纤维对无粘结预应力扁梁框架动力性能的影响。试验结果表明,钢纤维扁梁框架结构屈服后,其最大位移反应、最大恢复力反应和阻尼比均比普通混凝土扁梁框架要大,钢纤维可以有效提高扁梁框架在剧烈地震运动作用下的耗能能力,降低结构损伤。钢纤维对高强无粘结预应力扁梁框架的刚度、自振频率和动力放大系数的变化影响不大。

Seismic evaluation of fiber-reinforced high-strength prestressed concrete wide-beam frame was performed by pseudo dynamic test using MTS systems. The specimens consist of two frames with steel fibers and one with conventional concrete for comparison. The specimen was subjected to seven tests of increasing magnitude based on the E1 Centro ground motion. Dynamic response including acceleration, displacement, varying stiffness, hysteresis behavior and energy consumption corresponding to input excitation and the influence of steel fibers on dynamic behavior of high-strength prestressed concrete wide-beam frame are discussed. The results showed that the fiber-reinforced wide-beam frames exhibit larger response to on the internal dynamic response such as stiffness, natural frequency and dynamic magnification factor of high-strength prestressed concrete wide-beam frame.