Technical Note: Static Versus Cyclic Load Capacity of Side Chairs Constructed with Mortise and Tenon Joints

The effect of cross-sectional tenon geometry on static and cyclic load capacity of side chairs constructed with round-, rectangular-, and diamond-shaped mortise and tenon joints was investigated. Cyclic load capacity averaged about two-thirds of static load capacity for the joint configurations tested. For the configurations included in the test, chairs with mortise and tenon joints constructed with round-, rectangular-, and diamond-shaped tenons had static load to cyclic passing load ratios of 56.5, 66.8, and 69.2% for rectangular-, round-, and diamond-shaped tenons, respectively. These results indicate that useful relationships existed between static and cyclic performance of round mortise and tenon joints, which may simplify the design process for chairs that must pass cyclic performance tests.