9714605 Seible Advanced composite materials such as carbon, aramid, or glass fibers in polymer matrices, such as epoxies, vinylesters and polyesters, have shown outstanding mechanical and chemical characteristics to be of great interest to civil engineering design and construction. Recent developments in manufacturing technologies and the need for new and more durable materials for rehabilitation of existing civil structural systems and renewal requirements of the aging building and bridge inventory have shown that the light weight of these polymer matrix composites can be cost-effectively employed, particularly in the seismic retrofitting of buildings and bridges. A concept which emerges from this combination of conventional civil construction materials, and for the civil engineering sector new polymer matrix composites (PMCs), is that of concrete filled composite tubes (CCTs), where the concrete takes on the compression force transfer and the carbon shell the functions of (1) formwork for the concrete, (2) confinement of the concrete, and (3) tension force transfer in both longitudinal bending and shear. The thin advanced composite tubes and stabilized against local instabilities by the infill concrete which can be pressure grouted and contain normal or lightweight aggregates. The research aims to systematically develop the basis for a new framing system made of filament wound hybrid glass/carbon tubes and filled on-site fully or partially with concrete. The research focus will be in three areas namely, (1) the analytical modeling and characterization of the fully and partially grouted advanced composite tube system and the proposed connections, (2) development of optimized hybrid schemes and fabrication techniques, and (3) the experimental full-scale validation of CCT beams and connections. The analytical models will be calibrated and verified by the test results and used for subsequent parametric studies to form the basis for general design model developments for concrete filled advanced composite tube framing systems. ***
