STRESS-DISTRIBUTION AMONG LAMINATES IN LAMINATED POSTS IN REGION NEARABRUPT SECTION CHANGE

Four unspliced laminated posts were strain gaged and loaded in bending to determine how stresses are shared among the laminates around abrup t section changes. The posts were mechanically laminated 2x6s construc ted from three foil-length boards plus one half-length board which end ed abruptly at the center of the post length. The posts were tested to simulate both simply supported and cantilever beams. The posts were a lso simulated with FEAST (Finite Element Analysis of Spliced Timber; B ohnhoff, 1987) to compare test results with theoretical analysis. In t he region near an abrupt change, the full length laminate nearest the abrupt change had 11% more stress than would be predicted if the desig ner assumed that all laminates shared the load equally. The half-lengt h board did not develop its share of the post stress until around 1000 mm below the abrupt change. FEAST predicted stresses in an abrupt sec tion change post within 7% of measured stress.