Contraction and expansion losses through bridge constrictions

Seckin G., Yurtal R., Haktanir T.

JOURNAL OF HYDRAULIC ENGINEERING-ASCE, cilt.124, sa.5, ss.546-549, 1998 (SCI-Expanded) identifier identifier

Özet

The U.S. Federal Highway Administration (FHA) method for computing bridge backwater was modified on the basis of significantly large prototype data (Neely 1966; Bradley 1978). Both the water surface profile and the backwater amount given by the original FHA method, which was developed after extensive laboratory model studies, differed appreciably from those recorded on natural reaches around highway bridges. Although a satisfactory explanation for this discrepancy was not given, most of the design charts of the FHA method were modified according to the prototype data (Bradley 1978). Here, a clear-cut explanation is given, and a modification for the bridge subroutine of the commonly used package program HEC-2 is suggested.

The U.S. Federal Highway Administration (FHA) method for computing bridge backwater was modified on the basis of significantly large prototype data (Neely 1966; Bradley 1978). Both the water surface profile and the backwater amount given by the original FHA method, which was developed after extensive laboratory model studies, differed appreciably from those recorded on natural reaches around highway bridges. Although a satisfactory explanation for this discrepancy was not given, most of the design charts of the FHA method were modified according to the prototype data (Bradley 1978). Here, a clear-cut explanation is given, and a modification for the bridge subroutine of the commonly used package program HEC-2 is suggested.