Adaptation of prestressed concrete to modular girder bridge design for advanced base construction

Abstract

The design of a series of precast prestressed concrete bridges for Naval advanced base construction is presented in this thesis. Girder type concrete bridges composed of modular prestressed girders of I).0, 60, 80, 100 and 120 foot spans have been conceived, in so far as possible, to reduce the materials and construction time required to a minimum^ consistent with good design practice and economy. The designs are slanted toward mass production precast methods of construction.

The modular girders have been proportioned in section to obtain an efficient use of the concrete and the high strength steel for prestressing, in accordance with varying dead load to live load ratios for the different span lengths and for the different construction phases o The method of approach has utilized the bridge deck slab as a contiguous portion of the prestressed tee shaped girders for the live load plus impact for H 20-S-44 loading conditions. Although the designs have been adapted for Naval advanced base construction, they are considered to be equally applicable to state or local highway commission projects. While the modular girders have been conceived principally for bridge construction, it is believed that they are adaptable, with only slight modification, to pier and wharf construction The use of such girders for pier and wharf construction furnishes the added advantage of long life due to the pro-[text is incomplete after this point.]