Towards innovative FRP fabric reinforcement in concrete beams: concrete–CFRP bond

The paper reports results of an experimental investigation into load response and failure behaviour of rectangular prismatic concrete beams reinforced with a combined flexural and shear reinforcement system made from carbon fibre reinforced polymer (CFRP) fabric. It is shown that CFRP U-channels with aggregate coating and an anchorage system consisting of a lipped channel section with intermittent closed loops were found to provide improved composite action between the CFRP reinforcement and concrete. These CFRP channels also ensured adequate strength and ductility before failure. Possible modes of failures of the beams are discussed as is the effect of the design parameters on the failure mode and the failure load. It is anticipated that the findings of this paper could be effectively used in other applications such as non-prismatic concrete geometries and as permanent formwork/reinforcement in thin concrete members where the flexible characteristics of dry CFRP fabrics are most useful

Seismic response of subsystems in irregular buildings

Permission is granted by ICE Publishing to print one copy for personal use. Any other use of these PDF files is subject to reprint fees.The component-mode synthesis method is applied to investigate the seismic response of secondary subsystems multi-connected to primary structures with irregularities. The proposed approach is more accurate than the cascade approximation, often used in the design practice, as the primarysecondary dynamic interaction is considered through the modes of vibration of the two components. The results of parametric analyses on a representative case study reveal similar trends in the displacements of the two components for mass irregularities in elevation, while sti ness irregularities in plan can result in significant torsional motion in both components, with the effects in terms of absolute accelerations being in general larger than those associated with the lateral drifts. This suggests that dynamic analyses with the component-mode synthesis method are particularly indicated for the seismic assessment of acceleration-sensitive secondary subsystems