The purpose of this research is to clarify the influence of difference in size of horizontal diaphragm on shear performance. The subject of research is horizontal diaphragm reinforced with shear key along CLT joints. At first, we confirmed the influence of difference in size of horizontal diaphragm on shear performance by experiment. Next, we confirmed it by numerical analysis of many patterns. As a result, the influence of difference in size of horizontal diaphragm on shear performance was shown.
