Effects of Loading Type and Loading Rate on Glulam Sipo Timber Beams for Flexural Loading

Abstract

Glulam wood elements are a high-performance structural material created by bonding layers of wood with structural adhesives. This study investigates the behavior of glulam beams made from the tropical timber species Sipo, which has limited representation in existing literature, under different loading types and rates in bending tests. Six Sipo glulam beams were tested: three under four-point bending and three under three-point bending. To assess the behavior at various loading rates, loads were applied at rates of 10 mm/min, 20 mm/min, and 30 mm/min. The results included load-displacement curves, ultimate load capacities, initial stiffness, and energy dissipation capacities. The study revealed differences between values obtained from three-point and four-point bending tests. Generally, beams subjected to three-point bending yielded higher values than those tested under four-point bending at the same loading rates. Notably, a significant reduction in values was observed for both testing methods at the loading rate of 20 mm/min.

Keywords

• Glulam
• Bending tests
• Strength
• Tropical timber

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