SEISMIC EVALUATION OF INFILLED REINFORCED CONCRETE FRAMES STRENGTHENED WITH FRPS
There is an urgent need to retrofit the deficient mid-rise reinforced concrete frame buildings in Turkey. For this purpose, an efficient FRP retrofit scheme was developed, in which hallow clay brick infill walls are utilized as lateral load resisting elements. The main premise of this practical retrofit scheme is to limit interstory deformations by FRP strengthened infill walls that are integrated to the boundary frame members through FRP anchors. Based on failure modes and measured deformation limits obtained from a large database of experiments, a diagonal compression-strut and tension-tie model is developed. The model is verified with a number of reinforced concrete frame test results with and without upgrades. Furthermore, results of a case study conducted on a typical building frame revealed that strength levels similar to that of a RC shear wall retrofit scheme can be obtained through the FRP retrofit alternative resulting in a displacement ductility of about four.
Shear behavior of masonry panels strengthened by FRP laminates
Abstract The present experimental study, performed on brick masonry panels strengthened by Fiber Reinforced Polymer (FRP) laminates, was aimed to investigate the efficiency of an alternative shear reinforcement technique. A series of nine unreinforced masonry (URM) panels and 24 strengthened panels have been subjected to diagonal compression tests. Different reinforcement configurations were evaluated. Experimental results pointed out that FRP reinforcement applied only at one side of the panels did not significantly modify the shear collapse mechanisms (diagonal splitting) of the URM; while double-side configurations provided a less brittle failure and a noticeable ultimate capacity increase. Performances of the different reinforcement configurations are compared in terms of strength and mechanism of failure; finally, experimental results are also used to calibrate existing analytical formulations for ultimate shear strength prediction.
Frequency selective surface design for blinds applications
In this paper, the reconfigurable blind structure with frequency selective surfaces(FSS) for the building applications are presented. Frequency transmission characteristics for different angles of the proposed blind-FSSs are investigated and verified through simulation and measurement. The simulation results show that we can implement the reconfigurable blind-FSS for multiband wireless applications. To verify the proposed paper, two kinds of blind-FSSs, crossed dipole FSS and circular ring FSS are fabricated and measurements are performed for different angles. The proposed structure in this paper which is very simple, can be easily applied to any planar surface for wireless security applications at low cost.