8.EFFECT OF SLAB DEFORMATION ON LATERAL FORCE DISTRIBUTION IN TWO-STORIED BUILDING : Part 1: Rigid Walled-Frames in Both Stories

Abstract

In buildings, in which frames with and without walls are provided, both bending and shearing deformations of the slab between walled-frames will be caused in horizontal direction by lateral forces such as earthquake if the distance between those frames is long. Therefore, frames situated in a middle part between two rigid walled-frames will deflect more than those near the ends and, consequently, the lateral force carried by the former become larger. In cases mentioned above, therefore, the conventional assumption, that the slab is perfectly regid and the laternal force is distributed uniformly upon every frames, can not be accepted in structural design. For the purpose of establishing a principle in structural design the author, in this paper, has made a theoretical analysis to find with respect to this problem the behaviors of two-storied building in which rigid walled-frames are provided in both stories. The assumptions used are: (1) Both bending and shearing deformations take place in a slab. For the simplicity of dealing with equations, however, the ends of the slab are assumed to be fixed for bending. (2) The rigidity of building in longitudinal direction is neglected. From the equilibrium of forces and the continuity of slab deformation under the action of lateral forces, finite difference equations for roof slab and second floor slab have been obtained and solved so that boundary conditions are satisfied.