Mid-rise Building Progressive Collapse Finite Element Modeling with Consideration of Occupant Egress

Open Access
Author:
Gabay, Zachary M
Graduate Program:
Civil Engineering
Degree:
Master of Science
Document Type:
Master Thesis
Date of Defense:
June 29, 2012
Committee Members:
  • Jeffrey A Laman, Thesis Advisor
  • Dr Daniel G Linzell, Thesis Advisor
  • Venkataraman Shankar, Thesis Advisor
Keywords:
  • Progressive Collapse
  • Steel Moment Frames
  • Occupant Egress
  • Abaqus
  • Finite Element Analysis
  • Nonlinear Static
  • Riks
Abstract:
A progressive collapse is characterized by initial local damage to a structural element leading to collapse of a large portion of the structure. Recently, investigation of collapse behavior and designing for progressive collapse has been greatly influenced by an increase in terrorist attacks to civilian type structures around the world. With the increased computing capabilities, numerical models have evolved into the primary method for evaluating structural response to extreme loading events. While, numerical models are a valuable investigative tool, modeling parameters must be carefully considered in order to appropriately represent the nonlinear material and geometric behavior inherent to a collapse event. This study considers the effects of three modeling parameters: element composition, element discretization, and load application on the performance of building model at a number of failure locations. Several preliminary investigations are considered to evaluate these parameters in beam and building bay models. Insight from these models were applied to full building models to investigate the collapse performance of the building subject to two load cases: the DOD (2009) collapse design load combination and a critical pedestrian load case representative of emergency occupant egress on the damaged structure. Results indicate that building model behavior is sensitive to all of the aforementioned modeling parameters as well as computational analysis procedures. None-the-less, with respect to load case, building behavior in response to the critical pedestrian egress loads were comparable to the UFC (2009) collapse design load and should certainly be considered for structures subject to extreme loading events.