Abstract
Ultimate strength of composite slab is strongly influenced by horizontal connection force between steel and concrete. Degrees of composite action in partial composite slab is expressed by a parameter given by horizontal connection force deviled by concrete force under full composite slab. Ultimate flexure strength of partial composite slab is calculated by this parameter. The horizontal connection force is composed of several kinds of force such as friction force, stud zibel force. Contribution of these components are examined by loading tests with real size specimens with and without stud on steel decks. Ultimate load capacity of partial composite slab with profiled sheeting can be obtained from the partial composite model. Results of calculation of this model are verified by nonlinear fiber stress model which uses measured strain distribution of slab specimens. Horizontal connection force obtained from the nonlinear fiber model coincide well with that of partial composite model.