Response of Bed Sediments on the Grade-Control Structure Management of a Small Piedmont Stream

2016 ◽  
Vol 33 (4) ◽  
pp. 483-494 ◽  
Author(s):  
T. Galia ◽  
V. Škarpich
Keyword(s):  
Control Structure ◽  
Bed Sediments ◽  
Grade Control

Analysis of ARS Low‐Drop Grade‐Control Structure

1992 ◽  
Vol 118 (10) ◽  
pp. 1424-1434 ◽  
Author(s):  
Steven R. Abt ◽  
Mark R. Peterson ◽  
Chester C. Watson ◽  
Scott A. Hogan
Keyword(s):  
Control Structure ◽  
Grade Control

LOW-DROP GRADE-CONTROL STRUCTURE

1998 ◽  
Vol 41 (5) ◽  
pp. 1337-1343 ◽  
Author(s):  
C. E. Rice ◽  
K. C. Kadavy
Keyword(s):  
Control Structure ◽  
Grade Control

scholarly journals Gap Scour at a Stepped Concrete Block Grade Control Structure

2010 ◽  
Author(s):  
J. S. Lai ◽  
S. C. Tsung ◽  
Y. M. Chiew ◽  
F. Z. Lee
Keyword(s):  
Control Structure ◽  
Concrete Block ◽  
Grade Control

Effect of grade-control structures at various stages of their destruction on bed sediments and local channel parameters

Geomorphology ◽  
2016 ◽  
Vol 253 ◽  
pp. 305-317 ◽  
Author(s):  
Tomáš Galia ◽  
Václav Škarpich ◽  
Jan Hradecký ◽  
Zdeněk Přibyla
Keyword(s):  
Bed Sediments ◽  
Control Structures ◽  
Channel Parameters ◽  
Grade Control

scholarly journals Case Study: Model Test on the Effects of Grade Control Datum Drop on the Upstream Bed Morphology in Shiting River

Water ◽  
2019 ◽  
Vol 11 (9) ◽  
pp. 1898 ◽  
Author(s):  
Ma ◽  
Wang ◽  
Nie ◽  
Yang ◽  
Liu
Keyword(s):  
Model Test ◽  
Control Structure ◽  
Scour Depth ◽  
Highway Bridge ◽  
Scaled Model ◽  
Bed Morphology ◽  
River Bed ◽  
Grade Control ◽  
Erosion Area ◽  
River Reach

This paper conducted an undistorted scaled model test (geometric scale λL = 1:80; the others are derived scales based on Froude similitude) of a 1.3 km-long river reach in Shiting River, China, investigating the impacts of the grade control datum (GCD, defined as the crest elevation of the grade control structure) drop on the upstream bed morphology. Three GCDs and six flood events (occurrence probability 1–50%, discharge = 600–4039 m3/s) were tested on the model. Experimental results indicate that, for a constant GCD, the increase in discharge deepens and widens the upstream river bed. For a lower GCD, the increase in channel depth and width caused by the increasing discharge is greater. For each discharge, the decrease in GCD induces a lower and steeper upstream river bed, widening the upstream main channel. For lower discharge, the GCD drop induces a head cut erosion area upstream of the grade control structure and the head cut erosion area is filled by the upstream sediment when the flow discharge is high. Experimental data also indicate that the maximum general scour depth at the 105th Provincial Highway Bridge is approximately independent of discharge for a constant GCD. For a lower GCD, the general scour depth at the 105th Provincial Highway Bridge increases slightly with discharge.

scholarly journals Secondary Currents with Scour Hole at Grade Control Structures

Water ◽  
2021 ◽  
Vol 13 (3) ◽  
pp. 319
Author(s):  
Mouldi Ben Meftah ◽  
Diana De Padova ◽  
Francesca De Serio ◽  
Michele Mossa
Keyword(s):  
Secondary Flow ◽  
Control Structure ◽  
Scour Depth ◽  
Control Structures ◽  
Secondary Currents ◽  
Scour Hole ◽  
Grade Control ◽  
Flow Motion ◽  
The Cross ◽  
Equilibrium Scour Depth

Most studies on local scouring at grade control structures have principally focused on the analysis of the primary flow field, predicting the equilibrium scour depth. Despite the numerous studies on scouring processes, secondary currents were not often considered. Based on comprehensive measurements of flow velocities in clear water scours downstream of a grade control structure in a channel with non-cohesive sediments, in this study, we attempted to investigate the generation and turbulence properties of secondary currents across a scour hole at equilibrium condition. The flow velocity distributions through the cross-sectional planes at the downstream location of the maximum equilibrium scour depth clearly show the development of secondary current cells. The secondary currents form a sort of helical-like motion, occurring in both halves of the cross-section in an axisymmetric fashion. A detailed analysis of the turbulence intensities and Reynolds shear stresses was carried out and compared with previous studies. The results highlight considerable spatial heterogeneities of flow turbulence. The anisotropy term of normal stresses dominates the secondary shear stress, giving the impression of its crucial role in generating secondary flow motion across the scour hole. The anisotropy term shows maximum values near both the scour mouth and the scour bed, caused, respectively, by the grade control structure and the sediment ridge formation, which play fundamental roles in maintaining and enhancing the secondary flow motion.

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