Title: Components of Lateral Deflection in Sway Frames
Author(s): J.F. Horvilleur, V.B. Patel, and K.A. Young
Publication: Symposium Paper
Appears on pages(s): 101-124
Keywords: drift components; flexural deformation; lateral deflection; lateral loads; racking deformation; reinforced concrete; serviceability; stability; stiffness; structural analysis
Reinforced concrete frames must be proportioned to satisfy three limit states, serviceability, ultimate strength, and stability under sustained loads. Both the stability and serviceability limit states are directly related to frame lateral stiffness. The lateral stability analysis of concrete frames (P-? effect) requires a determination of frame stiffness. Lateral frame stiffness also affects many important building parameters such as building period, mode shapes, response to seismic loads, and the dynamic portion of the wind for tall buildings. In order to accurately estimate the lateral stiffness of concrete frames, the structural analysis must capture the contribution of all significant sources of frame deformation. The paper includes a detailed discussion of the various components that contribute to the total lateral deformation of frames. Recommendations are made for concrete frames to account for the elastic and nonlinear deformations that occur within the clear length of the members and inside the beam-column joint.