A connecting fitting includes a vertical frame attachment section 15a that can be attached to an inner surface of a vertical web 7a of a vertical frame 7A, 7B by way of bolts B2 in a state where the vertical frame attachment section 15a is disposed along the vertical web 7a, a brace attachment plate 14, connected to the vertical frame attachment section 15a, which enables attachment of an end of a brace 10A, 10B at a position inward of the vertical frame 7A, 7B, and a fixing plate 11, welded to the vertical frame attachment section 15a, which can be fixed to a beam member 4 or a foundation 2 in a state where the fixing plate 11 is disposed along an outer surface of a lateral frame 8A, 8B facing outward in a state of being disposed to make up a frame shape.