Title:
Simplified Method for Nonlinear Dynamic Analysis of Shear-Critical Frames
Author(s):
Serhan Guner and Frank J. Vecchio
Publication:
Structural Journal
Volume:
109
Issue:
5
Appears on pages(s):
727-738
Keywords:
blast; frame structures; impact; nonlinear analysis; secant stiffness; seismic; shear; strain rates; time-history analysis
DOI:
10.14359/51684050
Date:
9/1/2012
Abstract:
A nonlinear static analysis method was recently developed for the performance assessment of plane frames. The primary advantage of this method is its ability to accurately represent shear effects coupled with axial and flexural behaviors through a simple modeling approach suitable for large-scale applications. In this study, this method is further developed to enable a dynamic load analysis capability under impact, blast, and seismic loads. Newly developed and implemented formulations are presented. Among them are an explicit three-parameter time-step integration method, based on a total-load secant-stiffness formulation, and dynamic increase factor formulations for the consideration of strain rates. The method is applied to 11 previously tested specimens, subjected to impact and seismic loads, to examine its accuracy, reliability, and practicality. The method is found to simulate the overall experimental behaviors with a high degree of accuracy. Strengths, peak displacements, stiffnesses, damage, and failure modes (including shear-critical behaviors) and vibrational characteristics are calculated accurately. The method provides unconditional numerical stability and requires a fraction of the computation time demanded by micro finite element methods.