Tetsuro Ono

Interaction between Over-Turning Moment and Shear Capacity of Seismic Light Gage Bearing Wall

Light gage structure, where the plate thickness is less than 2.3mm, is limited up to three story buildings in Japan. This type of structure is used mainly on residential and commercial buildings. Seismic force is one of the most important design factor; light gage bearing wall is usually used for the horizontal force resisting component. Light gage bearing wall is composed with light gage frame and structural laminated plywood or gypsum board. Usually, over-turning moment due to lateral force is negligible in low rise building; however, it is questionable to adapt the same theory in middle rise building. To clarify the effect of over-turning moment to the bearing wall on light gage structure, full scale testing was conducted in this study. From the full scale testing, following results were found. (1) Over-turning moment was mainly resisted by the couple forces of the stud; horizontal force was mainly resisted by screws which are connecting plywood or gypsum board to the light gage frame. (2) Effect to over-turning moment to the shear capacity was observed when the magnitude of the moment exceeded 50% of its capacity.