High-rise building made of CLT increases significantly its own weight. Therefore, the collapse of the wall bottom is concerned. Main purpose of this study is to verify the effect of the reinforcement with screws for avoiding the collapse of the CLT wall bottom by extreme vertical load. Test pieces of CLT wall bottom were reinforced by screws. As a result, we got better structural result with screw reinforcement than without screw. From these experimental results, the reinforcement of CLT wall bottom using screw at perpendicular angle to the fiber direction is effective in workability because it does not need seat-dig hole.
Conventionally, energy absorption of joints in wooden structure has been obtained by yield deformation of steel parts. However, we have tried to control behaviour such as rigidity type or ductility type with combinations of wood fibre direction using screws in wooden structure for joint design. We defined the combination ratio of wood fiber as Rp (Ratio of parallel). First, we used special large diameter bolts to get high rigidity and ductility with embedding into combinations of parallel and orthogonal fiber directions. Then, we used long-screw which are more common in the market. We made all CLT test pieces by ourselves. We have compared the joint behavior with experiments and analysis. As a conclusion, we got following results of this study. When Rp rises, rigidity will be higher. On the other hand, ductility will be higher when Rp falls. We suggest the relationship equation for Rp and the rigidity and ductility of the increase or decrease by the theoretical value.