Development of scour hole depth around setback abutment in a compound channel

In this study, a series of experiments in a flume was conducted to investigate the maximum scour hole depth that occurred due to the vertical contraction of the flow underneath a bridge deck model without a pier. The bridge model was tested under pressurized and weir type of flows governed by clear water conditions. Various parameters of flow, sediment, and geometric features of the bridge, such as approach flow depth, discharge, sediment size, girder depth and degree of submergence were varied to investigate their effects on the maximum depth of scour hole. A total of 102 experiments were conducted and two empirical equations were developed separately for pressure and weir flow types with the use of experimental data. Effects of the aforementioned parameters on the scour hole were also analyzed and discussed.

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Mechanical Analysis on the Scour of Submarine Pipeline

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.834-836.1369 ◽

2013 ◽

Vol 834-836 ◽

pp. 1369-1372

Author(s):

Yan Han

Keyword(s):

Critical Condition ◽

Mechanical Analysis ◽

Submarine Pipeline ◽

Hole Depth ◽

Balance Condition ◽

Scour Hole

The reason about the scour of the submarine pipeline is researched in this paper. Through the mechanical analysis about the sand grain in the downstream of the pipe, the critical condition about of scour start is derived. The balance condition about the scour is studied. Through the mechanical analysis about the sand grain in the scour hole, the maximal scour hole depth is got.

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Study on the Submarine Pipeline with Flexible Spoilers

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.501.431 ◽

2012 ◽

Vol 501 ◽

pp. 431-435 ◽

Cited By ~ 3

Author(s):

Yan Han

Keyword(s):

Pressure Distribution ◽

Pressure Difference ◽

The Other ◽

Submarine Pipeline ◽

Hole Depth ◽

New Methods ◽

Physical Experiments ◽

Scour Hole

Two new methods which use flexible spoilers to protect submarine pipelines are proposed. One is put flexible spoiler on the top of the pipe to make pipe self-buried. The other is put flexible spoiler under the pipe to stop the erosion under the pipe. Through physical experiments, the pressure distribution and scour hole around the submarine pipeline with flexible deflectors were studied. Experiment results point out that top flexible spoiler can increase the resistance of the pipe, increase the scour hole depth, accordingly make the pipeline be self-buried. The flexible spoiler under the pipe can reduce the pressure difference between both sides of the pipeline, diminish the scour hole depth obviously and even to stop scour.

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Experimental investigation of the effect of skew angle on partially or fully submerged deck scour

Canadian Journal of Civil Engineering ◽

10.1139/cjce-2019-0121 ◽

2020 ◽

Vol 47 (9) ◽

pp. 1027-1036

Author(s):

Müsteyde Baduna Koçyiğit ◽

Önder Koçyiğit ◽

Hüseyin Akay ◽

Gülay Demir

Keyword(s):

Experimental Data ◽

Bridge Deck ◽

The Other ◽

Flow Depth ◽

Clear Water ◽

Flow Conditions ◽

Skew Angle ◽

Hole Depth ◽

Scour Hole ◽

Contraction Scour

This paper presents the results of an experimental study investigating the effect of skew angle on clear-water contraction scour under a bridge deck at partially and fully submerged flow conditions. Two bridge deck models without a pier, one of which was located perpendicular to the flow while the other one was located with skewness of 15°, were used in the study. Forty experiments were performed for each deck model, 24 of which were under partially submerged and 16 were under fully submerged flow conditions. Analysis of the experimental data showed that as the discharge and approach flow depth increased, the maximum scour hole depth under the skewed deck model increased up to 25%–66% for fully submerged flow and 17%–57% for partially submerged flow conditions. Furthermore, the effect of skew angle significantly enlarged the width of the scour hole as you move along the skewed deck.

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Local scour around a bridge pier under ice-jammed flow condition – an experimental study

Journal of Hydrology and Hydromechanics ◽

10.2478/johh-2021-0014 ◽

2021 ◽

Vol 69 (3) ◽

pp. 275-287

Author(s):

Jun Wang ◽

Zhixing Hou ◽

Hongjian Sun ◽

Bihe Fang ◽

Jueyi Sui ◽

...

Keyword(s):

Flow Velocity ◽

Local Scour ◽

Bridge Pier ◽

Scour Depth ◽

Flow Conditions ◽

Hole Depth ◽

Open Flow ◽

Ice Jam ◽

Scour Hole ◽

Ice Jam Thickness

Abstract The appearance of an ice jam in a river crucially distorts local hydrodynamic conditions including water level, flow velocity, riverbed form and local scour processes. Laboratory experiments are used for the first time here to study ice-induced scour processes near a bridge pier. Results show that with an ice sheet cover the scour hole depth around a bridge is increased by about 10% compared to under equivalent open flow conditions. More dramatically, ice-jammed flows induce both greater scour depths and scour variability, with the maximum scour depth under an ice-jammed flow as much as 200% greater than under equivalent open flow conditions. Under an ice-jammed condition, both the maximum depth and length of scour holes around a bridge pier increase with the flow velocity while the maximum scour hole depth increases with ice-jam thickness. Also, quite naturally, the height of the resulting deposition dune downstream of a scour hole responds to flow velocity and ice jam thickness. Using the laboratory data under ice-jammed conditions, predictive relationships are derived between the flow’s Froude number and both the dimensionless maximum scour depth and the dimensionless maximum scour length.

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FLOW-3D MODELLING OF THE DEBRIS EFFECT ON MAXIMUM SCOUR HOLE DEPTH AT BRIDGE PIERS

10.3850/38wc092019-1850 ◽

2019 ◽

Author(s):

INÊS SOFIA PEREIRA MENDONÇA ◽

HUGO DANIEL LEITÃO CANILHO ◽

CRISTINA MARIA SENAFAEL

Keyword(s):

3D Modelling ◽

Bridge Piers ◽

Hole Depth ◽

Scour Hole

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Study of Scour Characteristics Downstream of Partially-Blocked Circular Culverts

Water ◽

10.3390/w12102845 ◽

2020 ◽

Vol 12 (10) ◽

pp. 2845

Author(s):

Nesreen Taha ◽

Maged M. El-Feky ◽

Atef A. El-Saiad ◽

Martina Zelenakova ◽

Frantisek Vranay ◽

...

Keyword(s):

Empirical Equation ◽

Discharge Rate ◽

Relative Energy ◽

Hydraulic Structures ◽

Scour Depth ◽

Blockage Ratio ◽

Densimetric Froude Number ◽

Hole Depth ◽

Discharge Rates ◽

Scour Hole

Debris accumulations upstream and through crossing hydraulic structures such as culverts cause the upstream water level and the downstream scour depth to increase, which can lead to structure failure. This experimental study aimed to investigate the effects of various inlet blockage ratios on culvert efficiency and scour hole depth. In a non-blocked case, various submergence ratios (S = 1.06, 1.33, 1.60, and 1.90) were tested with different discharge rates. In a blocked case, the effects of inlet blockage with various blockage ratios (Ar = 10%, 20%, and 30%) were seen as sediment blockage on the pipe bed or floating debris upstream of the culvert. The results show that as the submergence ratio increases, the maximum scour depth decreases at the same discharge rate, and the relative energy loss also decreases in the non-blocked case. In the sediment blockage (Ar d) case, the relative maximum depth increases with increasing densimetric Froude number and with an increasing blockage ratio. An empirical equation was developed to predict the relative scour depth under the present study conditions.

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