合肥新桥国际机场航站楼钢结构多点地震输入响应分析

Time-history analysis of seismic response of Hefei Xinqiao Airport Terminal subjected to non-uniform ground motions

地震地面运动的空间效应对大跨结构的动力响应有很大的影响.通过有限元软件ANSYS建立了合肥新桥国际机场航站楼模型,采用ANSYS中的时程分析模块对结构进行多遇地震下多点输入和一致输入的时程分析.选择了合理的视波速来考虑行波效应的影响.将多点地震输入响应分析得到的设计应力与一致输入进行了比较.结果表明,多点输入下设计应力比一致输入下设计应力增大的构件占有很大的比例.因此,在大跨结构的设计过程中,多点输入下的地震分析是必不可少的.应该应用构件的设计应力比来调整一致输入地震响应的结果.

Spatial variation of earthquake ground motion has great influences on the dynamic responses of large-span structures. In this paper, the dynamic model of Hefei Xinqiao International Airport terminal is established using the FEM software ANSYS. The time-history method is used in the seismic analysis of the terminal under either the uniform excitation or the multiple excitations. Reasonable wave velocities are selected to consider the wave-passage effect, which is the major effect of the multiple excitations. The design stresses, in which seismic effect is considered, of the terminal members under multiple excitations have been compared to that under uniform excitation. The results indicate that the design stresses of a big proportion of members may be increased by the multiple excitations effect. Thus, the seismic analysis under multiple excitations is indispensable as that under uniform excitation, in the design process of such long span structures. And the ratio of design stress of every member should be used to adjust the seismic response under uniform excitation.