Load-carrying capacity and fatigue resistance of RC slabs using UFC panels with lap joints

To integrate RC slabs and UFC panels into a single piece construction, the UFC panels were placed in the longitudinal direction of bridges, steel bars were arranged on the UFC panels, and concrete was cast on the panels. In this case,lap joints need to be installed between the UFC panels with a core of φ30mm in every 300mm distance away from each others. To evaluate the load-carrying capacity of RC slabs using UFC panels with lap joints, the authors conducted tests of specimens with the following three types of lap joints under running loads. The first type was concreteinjected into the cores. The second type was UFC cylinders inserted into the cores. The third type was steel round bars inserted into the cores.As a result, the load-carrying capacities of RC slabs using UFC panels with the lap joints of concrete-injected cores, the UFC cylinders and steel round bars were 1.24, 1.31 and 1.46 times larger than ordinary RC slabs, respectively. Moreover, the fatigue resistance results evaluated by looking at the equivalent cyclic frequency with fatigue test under running wheel load, the specimens with three types of lap joints had also been evaluated by the fatigue resistance. Furthermore, the proposed lap joints structure's week points and usage had also been evaluated in this paper. © 2011 The Society of Materials Science, Japan.