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.
OUT-OF-PLANE STRENGTHENING OF MASONRY WALLS WITH REINFORCED COMPOSITES
This paper presents an investigation into the effectiveness of using fiber-reinforced composite overlays to strengthen existing unreinforced masonry walls to resist out-of-plane static loads. A total of fifteen wall panels [1,200 × 1,800 × 200 mm (4 ft × 6 ft × 8 in.)] were tested. Twelve panels were assembled with fiber-reinforcing systems attached to the tension side, and the remaining three control walls were left without any external reinforcement. Two configurations of external reinforcement were evaluated. The first reinforcement configuration consisted of two layers of fiber-reinforced plastic webbing and the second consisted of vertical and horizontal bands of undirectional fiber composites. The three wall specimens without external reinforcement were tested to evaluate the change in the system strength and behavior with application of the external reinforcing systems. In addition to the two fiber configurations, the testing program also evaluated two methods of surface preparation of the walls, s...
On the ontology of particle mass and energy in special relativity
Einstein claimed that the fundamental dynamical insight of special relativity was the equivalence of mass and energy. I disagree. Not only are mass and energy not equivalent (whatever exactly that means) but talk of such equivalence obscures the real dynamical insight of special relativity, which concerns the nature of 4-forces and interactions more generally. In this paper I present and defend a new ontology of special relativistic particle dynamics that makes this insight perspicuous and I explain how alleged cases of mass–energy conversion can be accommodated within that ontology.