Short-Term Flexural Behavior of Prestressed Glulam Beams Reinforced with Curved Tendons

Abstract

The short-term flexural behavior of prestressed glulam beams reinforced with curved tendons was investigated via four-point bending of 12 glulam beams. These beams were equally divided into four groups of three identical specimens: one group of unreinforced beams, one group of prestressed beams reinforced with straight tendons, and two groups of prestressed beams reinforced with parabolic tendons. For the last two groups, the initial prestress force was applied in two levels. The results revealed that, in contrast to the failure mode of the unreinforced beams, the failure mode of the prestressed beams changed from brittle failure to ductile failure. The flexural capacity and the flexural stiffness of the prestressed glulam beams reinforced with straight tendons increased by 56.9% and 14.9%, respectively, compared with that of the unreinforced beams; for prestressed beams reinforced with parabolic tendons, the capacity and the stiffness increased by 54.4%–75.5% and 14.2%–15.5%, respectively. Based on the experimental results, a theoretical model for predicting the flexural stiffness and capacity of prestressed glulam beams was proposed. This model was validated with the test data.