Development of high-performance glulam beams of Pinus nigra with embedded CFRP for its application for a real case for structural rehabilitation

Abstract

This work presents the design, elaboration, analytical calculation and experimental results of laminated beams internally reinforced with pultruded carbon fiber (CFRP) of high mechanical performance. During the rehabilitation of the Chapel Courtyard of the Royal Hospital of the University of Granada (Head Office of the Rectorate), three sawn timber beams were found to be completely broken due to a high eccentric load. For this purpose, an exhaustive control was carried out to classify the lamellas that make up the laminated beams into three qualities according to their longitudinal modulus of elasticity measured by non-destructive tests. Once the beams were produced, elastic and non-destructive tests were carried out before and after embedding the reinforcement. Finally, one of the beams was subjected to a flexure to failure test as a control element, with the remaining beams being placed in the actual construction site. In addition, this work presents a novel method to calculate the static global modulus of elasticity with a formulation based on the strains recorded by strain gauges. In addition, an analytical formulation estimating the global shear modulus of the element is presented. The results show a considerable increase of the global modulus of elasticity due to the CFRP, improving the strength and ductility. Finally, the analytical results show a good correlation with the experimental results.