Analytical Evaluation of Inter-Story Beam Effects on Lateral Stiffness of Moment Frames

The effects of inter-story beam on lateral stiffness of one-story moment frame with an arbitrary span length and distance from main beam for preventing frame form soft story and weak story irregularities are evaluated in this paper. The two-dimensional analysis was performed based on the slope - deflection method. Initially, lateral stiffness of a one-story moment frame without inter-story beam was calculated, and then the coefficient of Increased Lateral Stiffness (ILS) due to inter-story beam was calculated for several states used to FRAME1 program. The results and graphs were adjusted for the effects of different factors on ILS, such as stiffness of the inter - story beam, ratio of column height to span length and the ratio of stiffness of the main beam to inter-story beam. In all cases, the range of optimal distance of the inter-story beam from main beam for achieving higher ILS is calculated.

کلیدواژه ها:

Lateral Stiffness ، Inter-story Beam ، Static Analysis ، Soft Story ، Weak Story