Experimental Study on Effect of Ogival Bridge Pier on Scour Hole Depth

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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Effects of Bridge Pier Position in a 180 Degree Flume Bend on Scour Hole Depth

Journal of Applied Sciences ◽

10.3923/jas.2010.670.675 ◽

2010 ◽

Vol 10 (8) ◽

pp. 670-675 ◽

Cited By ~ 4

Author(s):

A. Masjedi ◽

M.S. Bejestan ◽

H. Kazemi

Keyword(s):

Bridge Pier ◽

Hole Depth ◽

Scour Hole

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Experimental study for determination of collar dimensions around bridge pier

The Baltic Journal of Road and Bridge Engineering ◽

10.3846/bjrbe.2015.11 ◽

2015 ◽

Vol 10 (1) ◽

pp. 89-96

Author(s):

Afshin Jahangirzadeh ◽

Shatirah Akib

Keyword(s):

Experimental Study ◽

Temporal Trend ◽

Bridge Pier ◽

Scour Depth ◽

Scour Hole ◽

Scour Countermeasure ◽

Reduction Percentage ◽

Shape And Size

The shape and size of a collar is important to maximize its effect as a scour countermeasure. Current research shows that the depth of the scour hole is decreased by using rectangular collars around circular piers. This study determined the approximate optimum dimensions for rectangular collars to minimize the temporal trend of scouring around a pier model. Effects of different sizes of rectangular collars on a model pier were investigated both at the upstream and downstream of the flume. It was observed that irrespective of the rectangular collar dimensions the upstream and the downstream were estimated to be 0.86 and 1.42, respectively. The optimum collar width was estimated to be 2.8 times the diameter of the pier. By using this optimized collar dimension, the non-dimensional depth of scour reached a min value of 0.034 at 72 h. The reduction percentage of the scour depth reached 98% at 72 h.

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EXPERIMENTAL STUDY ON EFFECT OF SLOT LEVEL ON LOCAL SCOUR AROUND BRIDGE PIER

International Journal of Research in Engineering and Technology ◽

10.15623/ijret.2014.0302019 ◽

2014 ◽

Vol 03 (02) ◽

pp. 103-108

Author(s):

Ali Khodabakhshi .

Keyword(s):

Experimental Study ◽

Local Scour ◽

Bridge Pier

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Experimental Study and Prediction Maximum Scour Depth Equation of Local Scour Around Bridge Pier

10.23918/iec2018.27 ◽

2018 ◽

Author(s):

Mohammed Tareq Shukri ◽

M. Günal ◽

Junaid Kameran Ahmed

Keyword(s):

Experimental Study ◽

Local Scour ◽

Bridge Pier ◽

Scour Depth

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Experimental Study on Seismic Behavior of a New Type of Bridge Pier

ICCTP 2010 ◽

10.1061/41127(382)359 ◽

2010 ◽

Author(s):

Hua Zang ◽

Zhao Liu ◽

Yong-ming Tu ◽

Yun-mei Meng

Keyword(s):

Experimental Study ◽

Seismic Behavior ◽

Bridge Pier ◽

New Type

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A Hooked-Collar for Bridge Piers Protection: Flow Fields and Scour

Water ◽

10.3390/w10091251 ◽

2018 ◽

Vol 10 (9) ◽

pp. 1251 ◽

Cited By ~ 10

Author(s):

Su-Chin Chen ◽

Samkele Tfwala ◽

Tsung-Yuan Wu ◽

Hsun-Chuan Chan ◽

Hsien-Ter Chou

Keyword(s):

Laboratory Experiments ◽

Horseshoe Vortex ◽

Flow Fields ◽

Bridge Pier ◽

The Other ◽

Bridge Piers ◽

Vortex Strength ◽

Numerical Tests ◽

Scour Hole ◽

New Type

A new type of collar, the hooked-collar, was studied through experiments and numerical methods. Tests were conducted using a hooked collar of a width of 1.25b and a height of 0.25b, where b is the bridge-pier width. The hooked-collar efficiency was evaluated by testing different hooked-collar placements within the bridge-pier, which were compared to the bridge-pier without any collar. A double hooked-collar configuration, one placed at the bed level and the other buried 0.25b, was the most efficient at reducing the scour hole. In other cases, a hooked-collar positioned 0.25b above the bed slightly reduced the scour hole and had similar scour patterns when compared to the pier without the hooked-collar. The flow fields along the vertical symmetrical plane in the experiments are also presented. Laboratory experiments and numerical tests show that maximal downflow is highly reduced along with a corresponding decrease in horseshoe vortex strength for the experiments with the hooked-collar, compared to cases without the hooked-collar. The flow fields reveal that the maximum turbulent kinetic energy decreases with the installation of the hooked-collar.

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Effect of canal width contraction on the hydraulic parameters and scour downstream water structures

Limnological Review ◽

10.2478/limre-2018-0010 ◽

2018 ◽

Vol 18 (3) ◽

pp. 93-101

Author(s):

Mohamed A. Ashour ◽

Tawab E. Aly ◽

Mahmoud M. Mostafa

Keyword(s):

Experimental Study ◽

Experimental Models ◽

Width Ratio ◽

Hydraulic Parameters ◽

Flow Properties ◽

Canal Width ◽

Hydraulic Conditions ◽

Scour Hole ◽

Design Requirements ◽

Experimental Runs

AbstractThe dimensions of many water streams, which satisfy proper hydraulic conditions, may not be compatible with the designed dimensions of an irrigation work that needs to be constructed in some locations. The design requirements of such irrigation works may involve a contraction in the channel width in the required location. This contraction, of course, affects different flow properties and the scour hole formed downstream of these structures. Therefore, the present experimental study aims to investigate the effect of the transition angle and the contraction on the flow properties and on the scour phenomenon downstream water structures. Through 460 experimental runs, carried out on 20 experimental models, the study proved that, for an efficient hydraulic performance and economic design, the best transition angle (θ) for the approaches of water structures is 30° with a relative contracted width ratio (r = b/B) not less than 0.6.

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