Engineering Structures, a world renowned journal for scientific and technical papers on the topics of structural engineering and structural mechanics has recently accepted and published a paper entitled, “Toward an Economic Design of Reinforced Structures Against Progressive Collapse.”
In the paper, authors Salem, El-Fouly, and Tagel-Din discuss the use of the Applied Element Method (AEM) in the design of reinforced concrete structures against progressive collapse. Based on their research, the authors conclude that the use of AEM can bring about a 50% reduction in the amount of reinforcement in the structure compared to Linear FEM. This is because the user can easily model reinforcement details, taking into account material nonlinearity, large deformations, failure, separation and collision.
ASI is the only commercial company to implement the AEM in its software Extreme Loading® for Structures. The entire paper can be accessed using the link below.
Abstract: A three-dimensional discrete crack model based on the Applied Element Method is used to perform economic design for reinforced concrete structures against progressive collapse. The model adopts fully nonlinear path-dependent constitutive models for concrete and reinforcing bars. The model applies a dynamic solver in which post-failure behavior, element separation, falling and collision are predicted. First, the model is used to study the behavior of multi-story reinforced concrete buildings designed in a traditional manner according to the ACI 318-08 and subjected to accidental removal of one or two central columns at the ground level. In an iterative way, the model is then used to investigate a safe design against progressive collapse for such extreme loading case. Based on the analytical results of the AEM, it can be concluded that the collapse of only one column would not lead to any progressive collapse of the studied reinforced concrete structure. However, the collapse of more than one column may lead to a progressive collapse of a considerable part of it. It is concluded also that the AEM could be successfully used as an analytical tool to suggest economical designs that are safe against progressive collapse of reinforced concrete structures.
H.M. Salem, A.K. El-Fouly, H.S. Tagel-Din, Toward an economic design of reinforced concrete structures against progressive collapse, Engineering Structures, In Press, Corrected Proof, Available online 28 July 2011, ISSN 0141-0296, DOI: 10.1016/j.engstruct.2011.06.020.