The paper deals with the design requirements for reinforced concrete diaphragms. Although diaphragms are primary members
 of the seismic force resisting system, ductile detailing of
diaphragms is not considered to be required. While the design
of diaphragms in regular framed buildings is straightforward, the analysis of transfer diaphragms involves more complex design criteria. Special considerations related to precast diaphragms are dealt with
in more detail.