Study on the strong earthquake failure mechanism of space grid structure considering rotational ground motion

Space grid structures are increasingly being utilized in public buildings due to their exceptional structural performance. Given that these structures are commonly located in areas with high pedestrian traffic and significant investments, damages incurred during an earthquake could result in significant economic losses and casualties. To explore the rotational seismic response of space grid structures, this study employs the frequency domain method to compute the rotational seismic motion. Using the Lushan Middle School Comprehensive Hall's structural form as a reference, a finite element model of the space grid structure is established. Three types of seismic motions, namely three-way translational, three-way rotational, and six-way translational and rotational, are input into the structural model to investigate strong seismic translation and rotation coupling effects. The impact and features of rotational seismic motion on space grid structures are explored by studying the influence and characteristics of rotational seismic motion. Under varying seismic motion inputs, the failure mechanisms of typical space grid structures' translational and rotational components are also determined.