ABSTRACT
CARBON FIBRE COMPOSITES AS STRUCTURAL REINFORCEMENT IN A NUCLEAR INSTALLATION Bonded reinforcement for seismic strengthening
H.N. GARDEN Taywood Engineering, Middlesex, UK
Abstract This Paper describes the experimental evaluation of a novel system for restoring the original steel reinforcement contribution in load bearing concrete walls affected by yielding of the steel due to structural and thermal effects. Strips of a carbon fibre reinforced polymer (CFRP) laminate were bonded to the concrete in line with the reinforcement, restoring the original stiffness and strength contribution of the embedded steel. The CFRP material provided a rapidly installed reinforcement system, allowing the work to be undertaken during a strict outage period of just three weeks in this first UK application of CFRP in an operating nuclear station. The restoration of the walls to their original condition ensures the structures meet hazard loading criteria, as required by the Independent Nuclear Safety Assessors (INSA). The initial load tests of the bonded system are reviewed. A selection of the bonded laminates and the underlying concrete cracks were instrumented and are now being monitored remotely, demonstrating the effectiveness of this reinforcement system. Keywords: Carbon fibre reinforced polymer (CFRP), epoxy adhesive, hazard loading, power station, reinforced concrete, shear load tests, tensile load monitoring
1 Introduction
1.1 The use of composites for strengthening The rehabilitation of reinforced concrete and other structures has been achieved for many years using externally bonded steel plates. Disadvantages of this method include transporting, handling and installing heavy plates and corrosion of the plates. The use of composite materials overcomes these problems and provides equally satisfactory
solutions. It is both environmentally and economically necessary to apply rapid, effective and simple strengthening techniques for the upgrading of existing civil infrastructure. An excellent example of this is in the nuclear power industry which demands minimal disruption of facilities to ensure continuous production of electricity.
