Results 211 to 220 of about 2,667 (262)

Local Scour at Skewed Piers

Journal of Hydraulic Engineering, 1998
Dimensional analysis of the variables influencing local scour at skewed piers brings into issue the generality of skew factors apparently related only to skew angle, α, and pier aspect ratio, L/b, for a particular pier shape. This note discusses this issue and provides insights into flow-field and scour-geometry changes at skewed piers.
R. Ettema, E. A. Mostafa, B. W. Melville, A. A. Yassin   +3 more
openaire   +1 more source

Local Scour at Complex Piers

World Environmental and Water Resource Congress 2006, 2006
A methodology to predict local scour depth at a complex pier is presented that recognises the relative scouring potentials of the components of complex piers, and the transition of scouring processes occurring for varying pile-cap elevation. Scour depths are predicted over the entire range of possible pile-cap elevations using a combination of existing
Bruce Melville, Stephen Coleman, Stephen Priestley   +2 more
openaire   +1 more source

Local and Contraction Scour at Bridge Abutments

Building Partnerships, 2000
In most experimental studies on erosion at bridge piers and abutments, the value of the blockage ratio b/B between the transversal obstacle dimension and the flume width is kept as small as possible (typically b/B b is not small compared to B so that the average acceleration due to contraction is expected to increase the scour effects of the ...
openaire   +2 more sources

Ultimate Dimensions of Local Scour

Journal of the Hydraulics Division, 1981
A mathematical method is presented for determining the ultimate dimensions of local scour from relatively short term measurement of the progression of scour with time. The method involves plotting the logarithm of the rate of change of the scour dimension against the logarithm of time. A hyperbolic curve is fitted to the plotted data, and the asymptote
Fred W. Blaisdell, George G. Hebaus, Clayton L. Anderson   +2 more
openaire   +1 more source

Local scour in rivers

Journal of Geophysical Research, 1961
It has been found that the scour in rivers is influenced not only by water velocities but also by the curvature of streamlines. An obstacle with an arbitrary shape placed in a stream produces curvatures, which are the origin of a scour and which have an intensity expressed in terms of the velocity at the surface, the velocity in the neighborhood of the
openaire   +1 more source

Controlling Mechanism of Local Scouring

Journal of Hydraulic Engineering, 1990
Experimental study of clear water scouring around a circular cylinder shows that the scour mechanism is coupled to the three-dimensional separation of the upstream boundary layer and the periodic vortex shedding in the wake of the cylinder. The first scour appears in the wake of the cylinder.
openaire   +1 more source

Similarity Laws for Localized Scour

Journal of the Hydraulics Division, 1966
The object of this study is to develop similarity criteria for sediment-transport rate and for scour depth in localized-scour situations. The principal assumption is that in an area of localized scour, the velocity and velocity distribution are the results of the disturbance element around which scour was occurring.
openaire   +1 more source

Local Scour at Bridge Abutments

Journal of Hydraulic Engineering, 1992
Laboratory data for local scour depth at bridge abutments are presented. These include sufficient data to demonstrate the effects on scour depth of abutment length, flow depth, and abutment shape and alignment. In addition, some data for the effects of sediment characteristics, flow intensity, and approach channel geometry are given.
openaire   +1 more source

Local Scour Around Cylindrical Piers

Journal of Hydraulic Research, 1977
A “state of the art“ report on the subject of local scour around cylindrical piers is given here. After a description of the scouring process, a critical review of literature on model and field data is presented, and the empirical data are compared with theoretical considerations.
H. N. C. Breusers, G. Nicollet, H.W. Shen   +2 more
openaire   +1 more source

Local scour at open-channel junctions

Journal of Hydraulic Research, 2010
High bed-shear stress resulting from secondary flows and velocity increase at a channel junction cause local erosion and deposition in natural rivers and earth-lined channels. Herein, the scour patterns at the junction of two loose bed channels were studied under clear-water conditions.
S. Mahmood Borghei, Aidin Jabbari Sahebari   +1 more
openaire   +1 more source