A plastic design theory for reinforced and prestressed concrete shell roofs

A theory is proposed which provides a simple method for designing shell roofs, including prestressed shells. This method takes into account the effect of the plasticity and cracking of the concrete as the ultimate load is approached. The theory considers two possible limits of shear stress distribution across a transverse section, and it is shown that the bending moment does not vary greatly between these limits. The theory is intended as a basis for experimental work which is to be carried out in the near future at Imperial College.