Reinforced concrete slabs are often designed using elastic stress fields at the ultimate load in conjunction with the Wood-Armer yield criterion. This procedure often leads to high concentration of reinforcement in regions of 'stress concentration'. This can be avoided by smoothing out the peaks in such a way that the ultimate load carrying capacity is not affected. This is equivalent to the standard procedure of 'redistributing' forces in the design of reinforced concrete structures. In any such procedure, care has to be taken to ensure that the behaviour of slabs at working loads is not affected. This paper explores the possibilitity of using nonelastic stress fields in the design of reinforced concrete slabs. Nonelastic stress fields are obtained by treating the slab as an elastic-perfectly plastic plate obeying von Mises yield criterion. By this approach, a variety of stress fields at different levels of plasticity spread but all resisting the same ultimate load can be obtained. Slabs are then designed using these stress fields in conjunction with Wood-Armer criterion. The designed slabs are then examined for their performance throughout the entire load history using a nonlinear finite element program based on LAYER approach in which the slab is divided into a series of horizontal layers of steel or concrete each being in a state of plane stress. It is concluded that very high levels of plasticity spread can be used to produce viable designs. The total steel consumption is practically unaffected by the level of plasticity spread used.

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