Analysis of the elasto-plastic seismic response of an ultra large span structure

Seismic analysis methods of large-span structures mainly include response spectrum method, random vibration method and time history analysis method. Comparing with the first two methods, time history analysis method exhibits better accuracy. For the ultra large span structure of the Xiamen west railway station, ANSYS and ABAQUS were employed to perform three-dimensional analyses. Dynamic elasto-plastic time-history analysis was then conducted to study the dynamic response of the structure and the degree of damage of key structure members.The analysis results showed that maximal story drift of the structure under rare earthquakes can satisfy the requirement of seismic code. The joint regions where tower columns connect the grid structure with high and low spans basically can meet the shear resistance demand, and it was suggested that steel skeleton be embedded into tower columns to improve their shear performance. The side columns and steel roof are also safe under seismic action. The horizontal and vertical displacements of the main truss chords are well under control, and the steel roof is stable. Generally speaking, this building structure can fulfill the principle of ‘no collapse under seldom earthquake action' specified in the national seismic design code.