Abstract：Multisupport seismic excitation is crucial to seismic response analysis of ultralong span structuresThe apparent wave velocity is an important parameter for multisupport seismic excitation, and so far no unified understanding of its determination methods has been attainedBesides, in the multisupport seismic excitation analysis, the influence of the foundation stiffness on the structure is not taken into accountIn this work, the factors affecting the apparent wave velocity were analyzed and the method of determining the apparent wave velocity of multisupport seismic excitation was proposedThe model and the calculation method of considering the foundation stiffness in seismic response analysis were proposedBased on the design of one airport terminal building, a calculation model was establishedThe timehistory analysis method was applied to studying the influences of the apparent wave velocity and the foundation stiffness on the multisupport seismic excitation of ultralong span structureThe results show that the magnitude of the apparent wave velocity directly affects the structure under multisupport seismic excitation and the value of the apparent wave velocity shall be taken reasonably in practice; the influence of foundation stiffness on the traveling wave effect of ultralong span structure decreases from the bottom of the structure to its upper part, and the influence of foundation stiffness on the lower floors of the structure is more significant; the rigid foundation may overestimate the effect of multisupport seismic excitations on the maximum floor shearing forces, the maximal interstory drift angle and internal force of frame columns, but its influence on the internal forces of the roof members is not significant.
