Jerome F. Hajjar - Department of Civil and Environmental Engineering

Apostolakis, Dargush, and Filiatrault, 2014

This paper makes use of a computational analysis approach that simulates evolution in order to analyze the effectiveness of different steel systems. The framework used within this paper is a Moment-Resisting Frame that is equipped with Post-tensioned Energy Dissipating Connections, and compares it to the Moment-Resisting Frame without Post-tensioned Energy Dissipating Connections using the aforementioned system.

System Concept

The system analyzed within this study is a steel moment-resisting frame (MRF) that is fit with post-tensioned energy dissipating (PTED) connections in order to make the system self-centering. The use of PTED connections instead of welded connections is intended to reduce production cost, as well as to reduce both the maximum interstory drift and the residual drift that the building will experience in the case of an earthquake. The system must have at least 75% of the base shear of a MRF system in order to fit within the parameters of the structure.

Analytical Study, Results, and Discussion

This paper tested a moment-resisting frame against a separate moment-resisting frame equipped with steel connections using a genetic algorithm that was created for use in simulating the evolutionary traits that develop among species. Using this system, the structures each have a 3 bit gene that codes for an element of the structure, and these 3 bit genes are repeated four times. Each structure is determined to carry a certain number of points based on a relative performance index (RPI) system that accounts for the performance of each gene. If the structure is outside of the parameters of the building, it receives a very poor RPI score. The structures are then subjected to a number of generations, and the lowest RPI are allowed to continue on until the structure is optimized.

Reference

Apostaolakis, G.., Darguish, G.F., and Filiatrault, A. (2014). “Computational Framework for Automated Seismic Design of Steel Frames with Self-Centering Connections,” Journal of Structural Engineering, 28. 2, pp 2.