Nature and Mechanism of Progressive Collapse in Industrialized Buildings. Report 3: Analytical Investigation of the Internal Load Distribution and the Mechanism of Progressive Collapse in Precast Concrete Large Panel Buildings

摘要

The effects of joint details and joint behavior on the mechanism of progressive collapse in large - panel, precast, concrete buildings was studied using both the finite element method and simple analytical models. A finite element computer code was developed to include elements which would aid in the modeling of unique characteristics of joints and joint behavior found in large panel buildings. Changes in the overall behavior of these details through the loading history of the damaged wall assembly were incorporated into the nonlinear incremental capability of the code. The bond - slip behavior of the joint reinforcement, the shear - slip behavior of the horizontal joint, and the adequacy of the vertical support provided for a wall were found to be critical aspects of joint behavior. The proper functioning of these details contributes to the ability of the damaged structure to sustain abnormal loading and reduce the possibility of excessive displacement and premature failure. Graphs and diagrams are included. Discussions of material and element stiffness, the transfer force method (a means by which unbalanced overstress can be redistributed throughout a structure), and computer codes used are appended, along with 68 references. (Author abstract modified).