ABSTRACT
CP 110 permitted flat slabs, i.e. floors or flat roofs without beams, to be designed by quite independent methods. To use the simplified method, BS8110 requires that there must be at least three panels of approximately equal span in each direction. Computers are frequently used to analyse flat-slab structures, and grillage analysis is frequently adopted. If drops are provided, the shearing stresses must be investigated for at least two sections, namely around the column head itself and around the perimeter of the drop. The critical plane around the drop is in the slab, at a distance from the edge of the drop equal to 1.5 times the effective depth of the slab. The requirements of BS8110 are much more specific regarding the transfer of moment from the slab to the supporting edge and corner columns.
