Threshold Value Method and its Application in Dynamic Analysis of Spatial Latticed Structures

Abstract

In traditional mode superposition method, vibration modes are truncated based on an accumulation criterion of mass participation factors. This proves to be efficient for the seismic analysis of multi-storey buildings but not so much for spatial latticed structures. This paper analyzes the mechanical differences between multi-storey buildings and spatial latticed structures under dynamic loads and develops two new types of structures, namely Member Shear Resistance Structures (MSRS) and Member Axial Resistance Structures (MARS), with which the application of the mass participation factor is clarified. This paper further introduces Dynamic Work Participation Factor (DPF) and Static Work Participation Factor (SPF) based on vibration mode energy contribution, and proposes Threshold Value Method (TVM) for dominant vibration mode selection. Numerical examples attest that TVM is both efficient and accurate in linear dynamic analysis of spatial latticed structures.