SEISMIC DESIGN OF COUPLED WALLS - A CASE FOR MIXED CONSTRUCTION

A new form of mixed construction, using structural steel beams to coup le reinforced concrete walls, is proposed as an alternative seismic la teral load resisting system. ''Shear critical'' steel coupling beams a re proposed as an alternative to diagonally reinforced concrete coupli ng beams and ''flexure critical'' steel beams are proposed in lieu of conventionally reinforced concrete coupling beams. Design and detailin g procedures for the steel coupling beams and their embedments in the concrete walls are presented. The results of full-scale, reversed cycl ic loading tests of portions of walls coupled with steel beams are pre sented. The responses of the steel coupling beams are compared with th ose of diagonally and conventionally reinforced concrete coupling beam s.