Investigation on Construction Quality Indices for Concrete Box Girders

Based on three bridge dismantlement, two construction quality indices were investigated in-situ, which consisted of duct grouting compaction of prestressing tendons, excess concrete rate in box girder. The result indicated that the excess concrete rate in box-girders, varied between 10% to 20% and the concrete excess centred at the top slab and bottom slab. The duct for prestressing tendons were only partially grouted, with over 50% ungrouted for longitudinal tendons and over 70% ungrouted for transverse tendons. Obviously, this would increased the prestress loss in the tendons,and increased the possibility of structure cracking. It was helpful for realising the true performance of box-girders.