SAFETY ENHANCEMENT OF URBAN STRUCTURES WITH STRUCTURAL RECOVERABILITY AND CONTROLLABILITY

Abstract

The novel concept presented in this paper is the use of fiber reinforced polymers (FRP) to control the performance of new and existing reinforced concrete (RC) structures during and after moderate to strong earthquakes. This study was conducted in three major steps. First, an overview of the different concepts considered to improve both the pre- and post-earthquake performances of new infrastructures is presented. Second, a mechanical model for FRP-RC structure damage control is defined. Third, based on the proposed definition for controllable structures and using the post-yield stiffness and permanent deformations as seismic performance measures, the results of scaled tests of different structural elements are examined. For virgin beams, strengthening new RC beams or those with initial damage using hybrid FRP are presented, and the results of using wet bonding between FRP and concrete as a new technique for the construction of structures are briefly discussed. In addition, the effectiveness of FRP jacketing in existing non-ductile RC bridge columns with different deficiencies for quick recoverability after an earthquake is scrutinized using a large experimental database. Finally, to achieve a recoverable and more durable structure, the performance of steel bars wound with different types of FRP as reinforcement is highlighted.