Local bending tests and punching failure of a ribbed UHPFRC bridge deck

Local bending tests were carried out on critical locations of a new type of steel-concrete composite bridge deck, as a part of the experimental validation of an innovative ultra-high performance fibre reinforced concrete (UHPFRC) ribbed slab made of segments assembled by post-tensioning. Local failure was identified as one of the possible critical aspects of the design, due to lack of information on the real capacities of UHPFRC materials in bidirectional bending and possible punching shear mechanism. Experimental validation of the design was first derived from the representation of Eurocode wheel models, with a standard 0.4 m × 0.4 m loaded zone. A reduced 0.19m × 0.26m had to be used for representing concentrated impacts, and the representation of pavement layers was eliminated, so that the local bearing capacity could be reached. It was finally obtained with a characteristic punching failure mechanism, the ultimate load corresponds to two to three times the nominal wheel load of the Eurocode.