Shear Force Capacity of Various Doweled Frame Type Furniture Joints

Abstract

Tests were carried out to determine the ultimate shear force capacity of numerous of doweled frame type furniture joints under controlled laboratory conditions. Sugar maple (Acer saccharum), soft maple (Acer negund), yellow poplar (Liriodendron tulipifera), sweetgum (Liquidambar styraciflua) and black walnut (Juglans nigra) were utilized in constructing the joint specimens, but all dowels were cut from yellow birch (Betula papyrifera) and sugar maple (Acer saccharum). Two types of specimens were used in the tests, including "in plane" and "out of plane" positions. Specimens were assembled with polyvinyl acetate adhesive. Specimens were tested under static load by applying shear forces. The results showed that the narrower dowel spacing provide greater shear force capacity for a specified rail width. It was deduced that there was a slight relationship between the shear strength of the wood used in the rail and the thickness of the rail and average ultimate shear force capacity of the joint. It was also demonstrated that the joints had essentially equal shear force capacity regardless of whether they were loaded in the flat wise or edgewise position. Furthermore, the average shear force capacity of dowel joints evaluated in this study could be estimated by developed predictive expressions.