GLASS-FIBER-REINFORCED HOLES IN LAMINATED TIMBER BEAMS

An experimental investigation of glass fibre reinforcement of glued la minated timber beams is presented. A polyester resin is used both as m atrix and adhesive between the reinforcement and the wood. The main pa rt of the work considers beams with large holes tested in three point bending. Circular and rectangular holes, centred at quarter length of the beams make the strength of wood perpendicular to the grain become critical. Great improvements of strength are obtained with the glass f ibres. A comparison between various kinds and combinations of glass fi bre reinforcement is made. Further, the reinforcement applied as repai r of earlier cracked beams is investigated with positive results. One series of beams without holes is reinforced and tested in four-point b ending.