Abstract
It is effective to apply lightweight concrete to reinforced-concrete (RC below) deck in making lighter weight bridge superstructure. It is, however, reported that the fatigue durability of light-weight RC deck is inferior to that of ordinary RC deck with the equivalent design compression strength. On the other hand, the expansive additive is used to reduce initial cracks of RC decks, and it is confirmed that the expansive additive is effective to enhance fatigue durability. The aim of this research effort is to put the lightweight RC bridge deck to practical use, which includes proper amount of the expansive additive in order to induce chemical prestressing within the deck. The hardening characteristic and expansion characteristic of the lightweight concrete combined with expansive additive are confirmed through variety of component tests using small specimens, and it is also confirmed that the deck has superior fatigue durability compared to ordinary RC one through a series of wheel load driving tests using actual-sized deck specimens.
