Bending strength and stiffness analysis of butt-jointed glulam beams for residential construction

A study was conducted on five-lamination butt-jointed glued laminated timber (glulam) to assess the potential for using low-grade lumber for floor beams in residential construction. An equation based on the equivalent notch method of notched wood beams was developed to predict the bending stiffness reduction caused by butt joints in the glulam beam. The load-carrying capacities of the beams were estimated using the effective section modulus of the weakest butt-jointed sections. The bending strength and stiffness properties of the beams with various placements of butt joints were computed. The bending stiffness of the beams measured from the experiment agreed with stiffness equation predictions. The effective section modulus gave a good conservative estimate for the load-carrying capacity of the butt-jointed beam. The results obtained indicate that applying the appropriate construction techniques with regard to the stiffness and load-carrying capacity can allow butt-jointed glulam beams can be practical for use in residential construction.

You must be logged in to download any documents. Please login (login accounts are free) or learn how to Become a Member