Local Scour around Tandem Double Piers under an Ice Cover

Sang, Liansheng; Wang, Jun; Cheng, Tiejie; Hou, Zhixing; Sui, Jueyi

doi:10.3390/w14071168

Cited by 8 publications

(11 citation statements)

References 24 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…In order to avoid the sand bed at the entrance/exit boundary from being scoured by the approach flow, the high and wide scour prevention plates of equal height were laid in the front and rear sections of the model sand bed as the bed fixing area, and their surface roughness was consistent with that of the sand bed. The model of the bridge pier in the dynamic-bed test section for the field mea ments was based on the combination of equal-diameter piers, according to the scaled-down model; the model pier diameter width D was 4.8 cm, the front and rea spacing was 8.6 cm, and the overall pier length was 24.3 cm, as shown in Figure 4 non-homogeneous sand with a median particle size of 0.51 mm and 0.63 mm (geom standard deviation [34] greater than 1.2) was laid at the bottom of the test section to ulate the riverbed conditions; the test was conducted under open-flow conditions an cover conditions for scour simulation, and under ice-cover conditions, polystyrene sheets (with a thickness of 3 cm) were used at the top of the test section to simula fixed ice cover. and the maximum scour depth around the pier during the test run.…”

Section: Computational Domain and Grid Informationmentioning

confidence: 99%

Refined Simulation Study on the Effect of Scour Environments on Local Scour of Tandem Bridge Piers

Gao

Xian-you

2023

Sustainability

View full text Add to dashboard Cite

Ice cover is a natural phenomenon unique to rivers in cold regions, and its existence is one of the reasons for the collapse of structural foundations of bridge piers across rivers. In order to understand the influence of different scouring environments on the hydrodynamics and sand bed morphology in the local scour holes around bridge pier foundations, this paper simulates the dynamic evolution process of the local scouring of tandem combination piers under open-flow and ice-cover environments, based on a turbulence model using the Reynolds-averaged Navier Stokes (RANS) method and a sediment transport model considering the slope collapse effect, respectively. This study also takes the vortex flow and shear stress distribution at different characteristic moments of the pier perimeter section as the penetration point to analyze the effect of the influence law of the scouring environment on the morphology and relative time scale of the scour hole, and makes a detailed comparison with the results of the indoor flume test. The results of this study show that: for local scouring in open-flow conditions, sediment initiation is doubly inhibited and the hydrodynamic forces in the scouring hole are weakened; the local scouring caused by ice cover contributes to the total scouring of the submerged pier within its coverage area, which significantly increases the depth and range of the local scouring hole; and, although the interaction of turbulent eddies and shear stress on the pier side is the main dynamic mechanism of the scouring generated around the pier, the two have a strong correlation. The results of this study, obtained by accurately quantifying the amount of eddies and shear stress around the pier, are the basis for the reasonable estimation of the maximum local scouring depth, which can provide a reference for the study of the evolution of the riverbed around submerged structures in cold areas and is essential to avoid structural damage to the piers and reduce the economic loss of traffic..

show abstract

Section: Computational Domain and Grid Informationmentioning

confidence: 99%

Refined Simulation Study on the Effect of Scour Environments on Local Scour of Tandem Bridge Piers

Gao

Xian-you

2023

Sustainability

View full text Add to dashboard Cite

show abstract

“…There are complex turbulent vortices near the bottom bed of the bridge pier, and the sand initiation around the pier is influenced by the vortex motion; many scholars [35][36][37] have conducted a lot of investigations on the structural characteristics of the vortex system around the pier, and this paper focuses on the correlation between the vortex coherent structure, bed shear stress and sediment transport on the pier side under different scouring environments.…”

Section: Local Field Characteristicsmentioning

confidence: 99%

Simulation Study on Local Scour Characteristics of Tandem Bridge Piers in a Straight River under a Changing Environment

Gao,

Mou,

2023

Sustainability

View full text Add to dashboard Cite

Hydrodynamics is a common manifestation that causes natural scouring of riverbeds, and it is one of the factors that exacerbate the natural disasters of local scouring of bridge piers, causing sustainability of environmental changes in the water. The evolution pattern and scour characteristics of the bed surface around the submerged structures under different scouring conditions vary greatly. In order to investigate the scour mechanism, the reformed group (RNG) turbulence model in computational fluid dynamics (CFD) simulation software (v11.2) was used to simulate the scour under the clear-water scour and live-bed scour environments, and different scour morphology characteristics around the tandem piers under the clear-water scour and live-bed scour environments were obtained in the final simulation. By capturing the cross-sectional vortex and bed shear stress during the scouring process, the characteristic pattern of scouring topography around the pier and the relationship between the scour hole structure scale were analyzed, and the relationship equation between the development of scour depth and time scale was established. The study shows that: under the clear-water scouring environment, the sediment transport rate lags behind, but the contribution time is superior; under the live-bed scouring environment, by the shading and reinforcement influence of the upstream piers, the extent and development of the downstream pier surrounding the scour hole is small; the development trend of the maximum sediment transport rate of the scour hole and the great value of the shear stress is more synergistic, and the peri-pier eddy is positively correlated with the bed shear stress; through the regression equation to compare the relevant test and simulation results, the two are in good agreement, indicating that the simulated local scour evolution law is consistent with the actual law.

show abstract

“…It is also confirmed that the zone of the maximum velocity tends to shift toward the mid-depth and closer to the channel bed. Considering the fact that flow structure around tandem piers or groups of piers is significantly different from single piers and scour depth around pile groups could exceed twice that of single piers [18]. Further research has focused on the study of peer groups, i.e., [18,19].…”

Section: Introductionmentioning

confidence: 99%

“…Considering the fact that flow structure around tandem piers or groups of piers is significantly different from single piers and scour depth around pile groups could exceed twice that of single piers [18]. Further research has focused on the study of peer groups, i.e., [18,19]. Wang and Liang, 2020 introduced a new approach for calculating scour in layered soils based on the equilibrium concept and considering the geo-mechanical properties of the soils with different resistance to erosion.…”

Section: Introductionmentioning

confidence: 99%

ML and CFD Simulation of Flow Structure around Tandem Bridge Piers in Pressurized Flow

Azma¹,

Kiyanfar²,

Liu³

et al. 2023

Computers, Materials &Amp; Continua

View full text Add to dashboard Cite

Various regions are becoming increasingly vulnerable to the increased frequency of floods due to the recent changes in climate and precipitation patterns throughout the world. As a result, specific infrastructures, notably bridges, would experience significant flooding for which they were not intended and would be submerged. The flow field and shear stress distribution around tandem bridge piers under pressurized flow conditions for various bridge deck widths are examined using a series of three-dimensional (3D) simulations. It is indicated that scenarios with a deck width to pier diameter (Ld/p) ratio of 3 experience the highest levels of turbulent disturbance. In addition, maximum velocity and shear stresses occur in cases with Ld/p equal to 6. Results indicate that increasing the number of piers from 1 to 2 and 3 results in the increase of bed shear stress by 24% and 20% respectively. Finally, five machine learning algorithms, including Decision Trees (DT), Feed Forward Neural Networks (FFNN), and three Ensemble models, are implemented to estimate the flow field and the turbulent structure. Results indicated that the highest accuracy for estimation of U, and W, were obtained using AdaBoost ensemble with R 2 = 0.946 and 0.951, respectively. Besides, the Random Forest algorithm outperformed AdaBoost slightly in the estimation of V and turbulent kinetic energy (TKE) with R 2 = 0.894 and 0.951, respectively.

show abstract

Local Scour around Tandem Double Piers under an Ice Cover

Cited by 8 publications

References 24 publications

Refined Simulation Study on the Effect of Scour Environments on Local Scour of Tandem Bridge Piers

Refined Simulation Study on the Effect of Scour Environments on Local Scour of Tandem Bridge Piers

Simulation Study on Local Scour Characteristics of Tandem Bridge Piers in a Straight River under a Changing Environment

ML and CFD Simulation of Flow Structure around Tandem Bridge Piers in Pressurized Flow

Contact Info

Product

Resources

About