1. Key Laboratory of Concrete and Prestressed Concrete Structures of the Ministry of Education, Southeast University, Nanjing 210096, China;
2. Nanjing Dong-Da Modern Prestressed Engineering Co., Ltd., Nanjing 210048, China;
3. Shanghai Key Laboratory of New Technology Research on Engineering Structure, SRIBS, Shanghai 200032, China;
4. State Grid Yangzhou Power Supply Limited Company, Yangzhou 225000, China
Abstract：A total of 15 glulam beams, including a group of unreinforced glulam beams, a group of straight-bonded prestressed glulam beams, two groups of parabolic-bonded prestressed glulam beams and three groups of parabolic-unbonded prestressed glulam beams, were tested to study their short-term flexural behaviors. The experimental results showed that the curved slot manufacturing method and gluing process were effective and strong strand-laminate bonds were realized. For prestressed glulam beams, the average value of friction coefficient ? was 0.0030, and the average value of ? was 0.10. Compared to the unreinforced glulam beams, the ultimate bearing capacity of straight-bonded prestressed glulam beams increased by 33.2%, the flexural stiffness increased by 27.2%. For parabolic-bonded prestressed glulam beams, the ultimate bearing capacity may be increased by 29.9% and 50.1% respectively, the flexural stiffness increased by 28.9% and 30.8% respectively. For parabolic-unbonded prestressed glulam beams, the ultimate bearing capacity increased by 23.7%, 32.3% and 7.9% respectively, the flexural stiffness increased by 17.3%, 18.8% and 20.4% respectively. The ultimate bearing capacity of curved prestressed glulam beams was slightly lower than that of straight prestressed glulam beams, and the bonded prestressed glulam beams showed better flexural behavior than the unbonded ones. Moreover, it was found that the increase of tensioning stress effectively improved the ultimate bearing capacity but contributed little to the improvement of flexural stiffness.
