BEHAVIOR OF CURTAILED WALL-FRAME STRUCTURES

The lateral load resistance of tall wall-frame building structures com prising a combination of moment-resisting frames and shear walls that are reduced in size or terminated entirely at intermediate heights is investigated. A generalized theory for the deflection of such structur es is developed on the basis of a continuum model, to show that curtai lment of the walls is not necessarily detrimental to the performance o f the structure. Indeed, if the walls are curtailed within a certain h eight region the forces in the upper part of the frame are reduced whi le the top deflection is negligibly affected. An expression for the de flection of curtailed uniform wall-frame structures is minimized to pr ovide guidance for the optimum level of wall curtailment to cause a mi nimum increase in the top deflection. Guidance on the level of curtail ment without detriment to the structure's performance for practical no nuniform wall-frame structures is given.