Steel-concrete composite bridges provide an efficient and cost-effective form of bridge construction. By utilising the tensile strength of steel in the main girder and the compressive strength of concrete in the slab, the bending resistance of the combined materials is greatly increased and larger spans are made possible.Two types of composite bridge are considered in this document. The typical multi-girder steel-concrete composite bridge, which consists of a number of steel girders with bracing in between and a slab on top, and a ladder deck bridge, which consists of two main girders with a number of secondary crossgirders in between that support and act with a deck slab. Authors: Raed El Sarraf, David Iles, Amin Montahan, David Easey and Stephen Hicks. Reproduced with kind permission from HERA NZ.