The difference between the steel and concrete composite-laminated action beam and the double steel and concrete composite action beam is in the connection of the top concrete slab and the steel top flange. The bending properties about the composite-laminated beam and the double composite beam in the negative flexural region are investigated in this paper. The relation of the cross section bending moment-curvature for the two types of composite beams under the action of negative bending moment are drawn by the whole process analysis method, and then the corresponding cracking moment, elastic ultimate bending moment and plastic ultimate bending moment are obtained. The analysis results have a good agreement with test data. Although the sectional bending stiffness and bending-carrying capacity of the composite-laminated beam and the double composite beam are comparable in the elastic state, the crack resistance of the composite-laminated beam is much better than that of the double composite beam.
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