Steel plate shear wall with tension-bracing for seismic rehabilitation of steel frames

A rehabilitation technique that utilizes a thin steel plate as a supplemental shear wall system for small, low-rise steel structures is described. In the proposed system, the plate and surrounding boundary elements are installed in the middle of the bay, separate from existing columns. This geometry intends to eliminate the need to strengthen the existing columns, as these typically would have been designed only for the combined forces of gravity and wind. The system employs supplemental elements as tension-only elements to speed up the construction work and to enforce strict capacity design principles (i.e., overstrength is capped). A prototype system was designed using a hierarchical flowchart and a simplified analysis model, and its performance was evaluated through large scale testing. The system achieved stable hysteretic behavior without showing major strength deterioration until large story drifts were reached. A high-fidelity FE model of the system was also developed to reproduce the experimental behavior. The model well traced the test results and was used as a tool for validating the effectiveness of the proposed system geometry. (C) 2011 Elsevier Ltd. All rights reserved.