双向偏心结构实用抗震计算方法的研究

Study on a practical calculation method of two-way eccentric structure under seismic actions

双向偏心结构的水平双向平动位移和扭转相互耦合显著,为此,对该类结构的实用抗震计算方法进行了研究。以单层双向结构为例,分析其模态特点和不同地震输入方向时的位移响应,表明异阶振型同向位移的乘积不为零和激励方向对位移响应影响显著。结合位移反应谱和随机振动原理,并引入激励输入角度,推导出实用的抗震计算方法,并与时程分析法进行了比较,证明该算法是合理的。

Based on the coupling among two horizontal translational displacements and torsion around vertical axis of two-way eccentric structure was obvious, a practical calculation method of this kind of structures under seismic actions was studied. Taking one story structure with two-way eccentricity for example, the modal characteristics and the influence of different seismic input angles on the displacement behavior were analyzed, showing that the product of the same directional modal displacement between different modals was unequal zeros and that influence was significant. Combing displacement spectrum, stationary random vibration method and the input angle of earthquake excitation, a practical seismic calculation method was proposed. The comparison between the results from the practical calculation and the results from time-history method was conducted, showing the proposed method was reasonable.