Physical Model Study Validation of Deep Tunnel Sewer Design Concepts

Saline intrusion can seriously affect the performance of outfall systems and an understanding of the mechanisms causing intrusion is important in the hydraulic design of outfalls, particularly for deep riser tunnelled outfalls. The paper outlines the reasons for the occurrence of saline intrusion, the problems that arise when it is present and the methods available for prevention and purging. The paper draws on recent work undertaken on the design of a major deep tunnel outfall system using a physical model and outlines some novel methods devised for purging of the system.

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Two-Dimensional Numerical Modeling of Flow in Physical Models of Rock Vane and Bendway Weir Configurations

Water ◽

10.3390/w13040458 ◽

2021 ◽

Vol 13 (4) ◽

pp. 458

Author(s):

Drew C. Baird ◽

Benjamin Abban ◽

S. Michael Scurlock ◽

Steven B. Abt ◽

Christopher I. Thornton

Keyword(s):

Numerical Modeling ◽

Physical Model ◽

Numerical Models ◽

Hydraulic Performance ◽

Physical Models ◽

Protection Measures ◽

Design Engineers ◽

Model Study ◽

Study Results ◽

Wide Range

While there are a wide range of design recommendations for using rock vanes and bendway weirs as streambank protection measures, no comprehensive, standard approach is currently available for design engineers to evaluate their hydraulic performance before construction. This study investigates using 2D numerical modeling as an option for predicting the hydraulic performance of rock vane and bendway weir structure designs for streambank protection. We used the Sedimentation and River Hydraulics (SRH)-2D depth-averaged numerical model to simulate flows around rock vane and bendway weir installations that were previously examined as part of a physical model study and that had water surface elevation and velocity observations. Overall, SRH-2D predicted the same general flow patterns as the physical model, but over- and underpredicted the flow velocity in some areas. These over- and underpredictions could be primarily attributed to the assumption of negligible vertical velocities. Nonetheless, the point differences between the predicted and observed velocities generally ranged from 15 to 25%, with some exceptions. The results showed that 2D numerical models could provide adequate insight into the hydraulic performance of rock vanes and bendway weirs. Accordingly, design guidance and implications of the study results are presented for design engineers.

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Canal Wave Oscillations from Expansion of I-84 Bridge in Boise, Idaho

Transportation Research Record Journal of the Transportation Research Board ◽

10.3141/2309-19 ◽

2012 ◽

Vol 2309 (1) ◽

pp. 200-205

Author(s):

William Rahmeyer ◽

J. M. Clegg ◽

S. L. Barfuss

Keyword(s):

New York ◽

Physical Model ◽

Unique Solution ◽

Wave Phenomenon ◽

Bridge Columns ◽

Bridge Abutments ◽

Wave Problem ◽

Model Study ◽

Bridge Crossing

Recent improvements and the widening of the I-84 Bridge crossing of the New York Canal in Boise, Idaho, have increased the number of bridge columns from 28 to 60. The resulting structure has two parallel rows of columns that extend across the width of the bridge longitudinally within the canal. After the widening of the bridge and addition of the bridge columns, the canal began experiencing an oscillating wave phenomenon that originated from the bridge columns and caused erosion of upstream and downstream canal banks and bridge abutments. A physical model study was conducted to investigate the wave phenomenon and determine what modifications to the columns or canal would be necessary to prevent the wave oscillations. The physical model was successful in simulating the wave phenomenon, and four different modifications for resolving the wave problem were tested in the model. A unique solution was found that used precast nose cones attached to selected columns. The nose cones have been installed in the prototype bridge crossing, and no wave oscillations have occurred since installation. This paper discusses the study to simulate the wave phenomenon and the four modifications that were evaluated to reduce or prevent wave oscillations.

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Physical model study of beach profile evolution by sea level rise in the presence of seawalls

Coastal Engineering ◽

10.1016/j.coastaleng.2017.12.002 ◽

2018 ◽

Vol 136 ◽

pp. 172-182 ◽

Cited By ~ 8

Author(s):

T. Beuzen ◽

I.L. Turner ◽

C.E. Blenkinsopp ◽

A. Atkinson ◽

F. Flocard ◽

...

Keyword(s):

Sea Level Rise ◽

Physical Model ◽

Sea Level ◽

Beach Profile ◽

Model Study

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A physical model study of the storage of low-grade heat in unsaturated chalk

Journal of Hydrology ◽

10.1016/0022-1694(82)90057-9 ◽

1982 ◽

Vol 56 (1-2) ◽

pp. 61-83 ◽

Cited By ~ 1

Author(s):

John B.W. Day ◽

J.H. Black ◽

N.A. Chapman ◽

D.H. Hall

Keyword(s):

Physical Model ◽

Low Grade ◽

Model Study ◽

Low Grade Heat

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Physical model study of bedrock scour downstream of dams due to spillway plunging jets

Journal of the South African Institution of Civil Engineering ◽

10.17159/2309-8775/2020/v62n3a4 ◽

2020 ◽

Vol 62 (3) ◽

Author(s):

A Bosman ◽

G R Basson

Keyword(s):

Physical Model ◽

Linear Regression Analysis ◽

Scour Depth ◽

Model Study ◽

Fissured Rock ◽

Scour Hole ◽

Plunging Jets ◽

Concrete Blocks ◽

Rock Bed ◽

Equilibrium Scour Depth

The erosive power of a free-falling high-velocity water jet, flowing from a dam spillway, could create a scour hole downstream of the dam, endangering the foundation of the dam. Despite extensive research since the 1950s, there is presently no universally agreed method to predict accurately the equilibrium scour depth caused by plunging jets at dams. These formulae yield a large range of equilibrium scour dimensions. The hydrodynamics of plunging jets and the subsequent scour of a rectangular, horizontal and vertical fissured rock bed were investigated in this study by means of a physical model. Equilibrium scour hole geometries for different fissured dimensions (simulated with rectangular concrete blocks tightly prepacked in a regular rectangular matrix), for a range of flow rates, plunge pool depths, and dam height scenarios were experimentally established with 31 model tests. From the results, non-dimensional formulae for the scour hole geometry were developed using multi-linear regression analysis. The scour depth results from this study were compared to various analytical methods found in literature. The equilibrium scour hole depth established in this study best agrees with that predicted by the Critical Pressure method.

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