An experimental study on embedment strength for bolted connections loaded perpendicular to the grain

For bolted connections in timber structures, calculation method based on European yield theory is well known and widely used in the world. On this equation, we need some material properties, embedment strength of wood, yield strength of bolt and each size of specimens. Based on some test results, the strength on the latest standard in Japan announced in public. On the other hand, failure modes in wood aren't considered enough. On this study, we conducted bearing tests based on BS EN 383 and 3-point-bearing test, using end-distance, bolts diameter and wood species as tests parameter. We arranged the specimens with or without clearance between specimen and loaded-steelplate to observe crack behavior. Additionally tension-loaded bolted specimens were analyzed by failure modes and the bearing strengths were calculated according to EYT equation. As a result, 2%off-set strength was corresponding with the crack-starting-strength on bearing tests. The cracked-strength of bolted connection was almost the same with the calculation result with 2%off-set strength.