Lateral Distribution of Static Loads in a Prestressed Concrete Box-Beam Bridge: Drehersville Bridge

摘要

The report describes the field testing of the first of five beam-slab highway bridges included in an investigation of the structural behavior of bridges supported with prestressed concrete box girders, and subjected to loading with test vehicles approximating AASHO H20-S16-44 loading. The test structure was one of the end spans of a three-span simply supported bridge with a cast-in-place concrete deck supported by five precast prestressed concrete box girders laterally spaced at 7 ft. 2 in. The test span was 61 ft. 6 in. in length. The testing program consisted of the continuous recording of girder deflections and surface strains at various locations on the girders, slab, curb, and parapet, as either one or two of the test vehicles were driven over the test span at a speed of approximately 2 mph. It was found that the distribution factors derived from the field measurements were substantially different from those used in the design. The test results indicated that full composite action was developed between the bridge deck, curb, and parapet. It was found that the results of superimposed single-vehicle runs closely corresponded to the results obtained from two-vehicle runs. Also, it was determined that tests on a partially gaged cross-section could be combined to simulated tests on a fully gaged section. (Author)