混凝土结构周期比分析

Analysis of Period Ratio of Concrete Structure

为了深入研究混凝土结构设计中用于控制结构扭转效应的一个重要参数——周期比,推导出了2自由度框架结构模型的周期比和与之相关的扭转系数的理论公式,并分析了结构质量中心(质心)与刚度中心(刚心)的偏离和结构周边抗侧移构件刚度这2个因素对结构周期比的影响;同时采用计算机软件SATWE建立简化的三层框架结构模型,分别对调整楼面荷载前后的荷载分布和刚度分布进行了分析。结果表明:理论推导和软件分析的结果一致,增加质量中心和刚度中心的偏离程度或增加结构周边抗侧移构件刚度,都能使结构周期比减小。

In order to deeply study the important parameter used for controlling the torsion effect in the design of concrete structures-period ratio, the theoretical formulas of this parameter and its related torsion coefficient of one 2-DOF frame structure model were deduced, and the influences of two factors which were displacement of stiffness center from mass center and stiffness of peripheral members on period ratio of concrete structure were analyzed; a simplified three-story frame structure model was established by using computer software SATWE and the analyses before and after the rearrangement of the load distribution and stiffness distribution of floor load were carried out. The results show that the theoretical deduction results coincide with software analysis results, and increase of displacement of stiffness center from mass center or stiffness of peripheral members leads to decrease of period ratio.