Investigation of mechanical properties of glulam beams made with screws or glue and reinforced with steel plates

Document Type : Research Paper

Authors

1 Department of Civil Engineering, University of Zabol

2 Civil Engineering Department

3 Department of Wood and Paper Industries, University of Zabol.

10.22034/ijwp.2023.1982938.1578

Abstract

Reinforcement of glulam beams to prevent an increase in the volume of the structural element and to reduce wood consumption is inevitable. The increased strength of these engineered products along with the limited use of other materials provides this issue. Comparing the strength of glulam beams with adhesive or screw connection was operated by making a variety of reinforcement designs. Glulam specimens of adhesives groups and screws were reinforced with straps and rebars. Prestressing was performed in one of the bolt screw treatments with an approximate amount of 5 kN. Calculations and statistical analysis show the significant effect of reinforcement designs and increase the strength of various types of adhesive beams. End holder sheets on glulam beams using steel straps play an effective role. Slip diagrams show that as the load increases, the slip increases almost uniformly. Next, the partial movement of the layers on each other is controlled by the end holder sheet and prevents the growth of the graph. However, the slip diagram of unreinforced glulam beams shows that the slip in the first part of the diagram has more growth than in the second area.

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Main Subjects


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