The European project SUREBridge - Analysis of laboratory test beams

The European research project SUREBridge (Sustainable Refurbishment of Existing Bridges) is developing a new concept for the structural strengthening of road bridges: glass fibre-reinforced polymer (GFRP) sandwich panels are installed on top of the existing concrete slabs; pre-stressed carbon fibre-reinforced polymer (CFRP) laminates are adhesively bonded to the bottom of the longitudinal girders. Laboratory tests were carried out on 6-m long beams subjected to four-point bending: one reference not strengthened concrete beam and three strengthened beams. Finite element models of the tested beams were developed by using the commercial software Straus7®. A fibre model with BEAM and LAMINATE elements was defined with specific non-linear stress-strain curves for the confined and unconfined concrete, steel reinforcements, GFRP, and CFRP. The theoretical load-deflection curves obtained through non-linear static analyses showed very good matching with the experimental results.