Optimal drift design model for multi-story buildings subjected to dynamic lateral forces

An optimal drift design model for a linear multi-story building structure under dynamic lateral forces is presented. The drift design model is formulated into a minimum weight design problem subjected to constraints on stresses, the displacement at the top of a building, and inter-story drift. The optimal drift design model consists of three main components: an optimizer, a response spectrum analysis module, and a sensitivity analysis module. Using a small example, the validation of the proposed model has been tested by a comparison of optimal solutions. Then, the performance of the optimal drift design model is demonstrated by application to three steel frame structures including a 40-story building. Various structural responses including lateral displacement and inter-story drift distributions along the height of the structure at the initial and final design stages are presented in figures and tables. Time-consuming trial-and-error processes related to drift control of a tall building subjected to lateral loads is avoided by the proposed optimal drift design method.