Observations of bridge abutment scour lead to a practical new approach for estimating realistic scour IIHR-Hydroscience and Engineering depths at bridge abutments. Prior design approaches usually led to unrealistically deep estimates of abutment scour depth. The observations presented stem from flume experiments conducted with abutments with approach embankments subject to a range of erodibilit...

When depth of flow past a river bridge exceeds opening under the bridge, the flow under the bridge becomes pressurized. The water is directed downward and under the bridge deck, causing increase in velocity and shear stress on the bed thereby increasing bed scour. This is termed as Pressure Flow Scour. The present study investigates the phenomenon of pressure flow scour resulting from a submerg...

This paper compares the application of two recently published guidance documents for risk-based assessment hydraulic actions on bridges, namely UK Design Manual Roads and Bridges Italian Ministry Infrastructure Transport’s Guidelines, to case study bridges (Staverton Bridge, UK; Borgoforte Italy). work is one first illustrate how apply these guidelines. Both present methods actions, while exhib...

Analysis and interpretation of monitoring data for the seabed bathymetry local to offshore windfarm foundations has shown how the scour develops in time and highlighted variations between sites with different seabed sediment characteristics, i.e. sands and clays. Results from European offshore windfarms have generated a unique dataset for comparison with previously published data. Where surfici...

Scour in bed material downstream weirs is considered the most unfavorable process which threats the overall stability of the weir. Weirs with oblique angle in the horizontal plan will affect the scour profile downstream the structure and may reduce it. The objective of this paper is to investigate the effect of oblique weir angle on the scour profile. Furthermore, the effect of V-notch angle on...

The modeling of flood-induced bend scour near embankment toes can provide important information for river engineering, embankment safety warnings, and emergency action management. During the rainy seasons, short-term general scour and bend scour are the most common causes for the failure of reinforced concrete embankments in Taiwan. To gain a deeper understanding of the scouring process near le...

Failures barrages or parts of them may be expected when excessive scour patterns are observed downstream of such structures. Severe and excessive scour may be largely due to unsymmetric operation of gates especially when a multi-vents barrage or regulator is being considered. Previous investigations proved that the scour patterns downstream hydraulic structures are functions of the bottom veloc...

Local scour around a cylindrical pier in a channel with an erodible bed or natural bed is a common problems in bridge or pile supported structure. The highly unsteady complex flow field around a circular pier produces scour hole mainly for the presence of vortices. The main mechanism that drives the formation and evolution of the scour hole around bridge pier is horse shoe vortex motion. In the...

The paper describes the range of scour types that may occur at bridge abutments, and addresses the extensive attendant difficulties confronting accurate estimation of abutment-scour depth. The difficulties, which include similitude aspects of laboratory experiments on scour at bridge abutments, complicate the development of reliable scour-estimation relationships. In a practical sense, the diff...