抄録
The present paper deals with the relation between maximum compressive load and witdth of wood-stud walls, and with the estimation of the maximum loads. Test walls were made of S-P-F lumber (204 D) and structural plywood of 7.5mm thick (Fig. 1). Before compression tests the walls were bent by small loads and the load-deflection curves were obtained. After the bending test the walls were compressed under centroidal loading until compressive failures occurred in the walls (Fig. 2).
The results obtained are as follows:
(1) Flexural rigidities of the walls were nearly constant for all the walls with various widths. Thus, plywood contributes little to the flexural rigidity of the walls (Fig. 3).
(2) Three different types of failure occurred in the walls: the breaking of plywood (Fig. 4), the delamination of plywood (Fig. 5), and the breaking at a knot in studs (Fig. 6).
(3) There were two levels in maximum compressive loads: the higher level corresponding nearly to the delamination of plywood and the lower one to the breaking of plywood (Table II).
(4) Mechanical models of the walls in compression were presented (Fig. 7), and the equation for the estimating the maximum compressive loads was derived from the models (Eq. (16)).
(5) It was proved that the estimation by the above equation gave a fairly good agreement with the experimental (Fig. 8).
