Abstract: An expansion joint structure to be placed between adjacent concrete slabs in a concrete slab system comprises a first profile element to be attached to an edge of a first concrete slab, and a second profile element to be attached to an edge of a second concrete slab, the profile elements being joined together by removable connecting strips such that there is a gap between the profile elements. The profile elements and connecting strips constitute a single continuous entity of extruded aluminum profile. The connecting strips are attached by outer edges to the profile elements through very thin neck portions that keep the elements together during the pouring of the slab. The expansion joint structure is positioned on the concreting base at the correct height prior to the pouring of the concrete slabs.