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Showing 1 to 15 of 15 for “"Scour hole"”.
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The Effect of Wall Jet Flow on Local Scour Hole
… measurements and measurements of the evolving scour hole shape were made. Detailed descriptions of the turbulent flow field over a fixed rough bed and for scour holes at equilibrium were obtained for a range of initial jet conditions. Fully turbulent, multiphase flow was modelled using the …
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Evaluation of the Jet Test Method for determining the erosional properties of Cohesive Soils; A Numerical Approach
… perpendicular to the soil surface, creates a scour hole which is measured at discrete time intervals. While the results of these tests are able to provide values of critical shear stress and soil erodibility, the results are often highly variable and do not consider certain aspects of scour …
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Scour in regions of flow separation with free-surface effects
… the flow regime is important because diving-jet scouring rates are substantially faster than surface flow scouring rates, and diving-jet scour holes form nearer to the structure. A bi-stable region exists in which either flow is possible with the same upstream and downstream flow conditions. …
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Remote sensing and localization of smart rocks with orientation-controlled magnets for real-time monitoring of bridge scour and riprap effectiveness
… for real-time monitoring of the maximum scour depth and the effectiveness of riprap mitigation measures. A smart rock is one or more stacked magnets encased in concrete that can automatically roll to the deepest point of a scour hole around a bridge pier and provide its location through …
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A computational fluid dynamics model for sediment movement based on the unit stream power approach
… unit stream power approach for the prediction of scour profiles. The unit stream power approach is employed to define the incipient motion criteria for the sediment particles by comparing the available applied stream power with the individual particle power requirements for motion (Rooseboom …
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Oceanographic considerations for the management and protection of surfing breaks
… salient was observed. Landward of the reef, a scour hole ~3 times the surface area of the reef has formed. The current literature on ASRs has primarily focused on reef shape and its role in creating surfing waves. However, this study suggests that impacts to the offshore bar, beach-state, scour …
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Burial of Short Cylinders Induced by Local Scour and Bedform Migration Under Waves Plus Currents
… of a short cylinder was determined by local scour around the cylinder and by a more global process associated with the presence of ripples and sandwaves. The role of bedform evolution on the burial of short cylinders was studied. For this purpose, a series of detailed measurements of …
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Numerical, field and laboratory studies of three-dimensional flow structures at river channel confluences
… those where bed discordance is due to local scour in the centre of the confluence, one or more cells have been identified. Thus, it is clear that both junction angle and bed discordance are important controls, but not how they interact or their relative effect under different circumstances. …
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Local scour at bridge piers
Local scour at cylindrical bridge piers in both uniform and non-uniform cohesionless sediments was investigated experimentally. The aim of the study was to improve understanding of local scour around bridge piers with sediment transport. Three empirical functions which relate the equilibrium depth …
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Using the movability number to model local clear-water scour in rivers
Local scour is associated with a considerable number of bridge failures worldwide. It occurs at bridge piers and abutments as a result of interactions between complex flow features and the channel bed. The number of factors involved in the interactions makes it difficult to predict. A lot of …
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Flow structure of an asymmetric large river confluence
… the effects of secondary circulation cells. The scour hole location and geometry within this confluence hydrodynamic zone are subject to change depending on the relative momentum of the two rivers with the zone of scour shifting outward and enlarging as the momentum flux of the lateral tributary …
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Data-Driven Risk Assessment of Bridges Subject to Corrosion and Scour
… degradation events, such as corrosion and scour, creates safety issues in the structural system and can lead to possible bridge failures. Collecting and analyzing inspection data provide a way to monitor and assess the safety condition of bridges. This thesis presents new methods for …
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Combined abutment and contraction scour in compound channels for extreme flood events
… the combination of abutment and contraction scour is investigated to better understand the scour mechanisms and scour patterns for extreme floods. Close-toreality scour events were physically simulated using models built at 1:45 and 1:30 geometric scales of two-lane bridge prototypes. Scour …
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Flow and sediment movement in stepped channels
… this purpose, and clear water flow, clear water scour, and sediment transport tests undertaken for a range of discharges and channel slopes. Three distinct flow regimes were observed for the clear water flow and clear water scour tests. They were stable tumbling flow, unstable tumbling flow, and …
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Bulle-Effect and its implications for morphodynamics of river diversions
… was found to result in formation of a scour-hole under the high-flow zone and subsequent deposition sediment under the flow-recirculation. The impact of the change in morphology of the channel on Bulle-Effect was also analyzed. The findings of this dissertation not only add to the …