结构设计中的扭转效应原理分析

Principle Analysis of Torsion Effect in Structural Design

实际工程中,由于质量和刚度的不完全对称、地震作用位置与刚心的不重合、地震动中扭转分量等因素影响,在地震作用下,结构不可避免地存在扭转效应。文章通过对结构动力学的运动方程及振型分解反应谱法的分析,对结构的扭转机理进行阐述,并通过算例加以说明。分析表明:当结构的质量和刚度完全对称时,只有地震动中的扭转分量才会引起结构的扭转反应。

In practical engineering, due to the incomplete symmetry of mass and stiffness, the misalignment of seismic action position and stiffness center, the torsional component of ground motion and other factors, the structure will inevitably has torsion effect under earthquake action. Through the analysis of the motion equation of structural dynamics and the mode-superposition response spectrum method, this paper expounds the torsion mechanism of the structure and illustrates it with examples. The analysis shows that when the mass and stiffness of the structure are completely symmetrical, only the torsional component in the ground motion will cause the torsional response of the structure.