Abstract: To improve the mechanical property of common glued-lumber beam, an reinforcing method is proposed, that steel plate is fixed on the bottom of beam by pasting or screwing. Bending test of 21 beams were conducted to analyze the influences of steel plate thickness, with or without the screwing on beam failure mode, bearing capacity and deformation capacity in comparison with common clued-lumber beam. The bearing capacities are respectively increased by 73.3%, 90.0% and 71.0% by pasting steel plates with thickness of 2 mm, 3 mm and 4 mm, indicating that as the thickness of the steel plate increases the bearing capacity increases first then decreases. When both pasting and screwing are used with the above values of thickness, the bearing capacities are increased by 76.4%, 96.9% and 148.6% respectively, indicating that bearing capacity increases with the thickness of the steel plate, and the reinforcing effect of thicker steel plate is obvious. With steel plate reinforcement, the ultimate deformation is increased by 6.2% to 61.1% than that of common glued-lumber beam, and the influences of the steel plate thickness and screwing are similar to that of bearing capacity. After verification of the glued-lumber beam reinforced with steel plate conformed on the plain section, the bending capacity calculation formula of similar constructional member is proposed. The average error between the theoretical value and testing value is less than 10%.

Key words: materials synthesis and processing technology, steel plate reinforced glued-lumber beam, bending performance, test research, failure mode, bearing capacity calculation