Scour at various hydraulic structures: sluice gates, submerged bridges, low weirs

Abstract

Prediction of likely scour depths is an important aspect of the design of hydraulic structures. While detailed guidance is available for the scour design of some structures, e.g. bridge foundations, scant information is available for many other structures. Recent, as yet unpublished, research findings for a number of fluvial structure types are presented herein. The research findings span scour downstream from sluice gates, scour in the vicinity of low weirs, together with a particular aspect of scour at bridge foundations that has previously received minimal attention. In each case, new data are presented, together with analyses of the data and simple (preliminary) design relationships are determined from the data. A feature common to bridges and low weirs is the form of the dependence of scour depth on flow intensity for clear-water and live-bed scour conditions. The new data are derived from small-scale laboratory experiments for non-cohesive (alluvial) bed materials; the research findings are limited accordingly.