Backwater computation for choked flood flows through bridge contractions

摘要

Choked flood flows caused by sever bridge contractions were studied in this paper. A new method for the computation of backwater elevation for choked flows through bridge contractions was proposed. This new method was derived from the conservation of energy and the water continuity. The critical flow condition at the contraction, which forms a control section for the flow upstream of the contracted reach, was considered. The applicability of the proposed method was tested by a large flood which occurred at I-5 bridge over Los Gatos Creek neat Coalinga, California in 1995.