scholarly journals Turbulence Characteristics before and after Scour Upstream of a Scaled-Down Bridge Pier Model

Water ◽  
2019 ◽  
Vol 11 (9) ◽  
pp. 1900 ◽  
Author(s):  
Seung Oh Lee ◽  
Seung Ho Hong
Keyword(s):  
Sediment Transport ◽  
Current Knowledge ◽  
High Water ◽  
Bridge Pier ◽  
Quadrant Analysis ◽  
Mean Flow ◽  
Protection Measure ◽  
Pier Scour ◽  
Turbulence Characteristics ◽  
Before And After

Bridge pier scour is one of the main causes of bridge failure and a major factor that contributes to the total construction and maintenance costs of bridge. Recently, because of unexpected high water during extreme hydrologic events, the resilience and security of hydraulic infrastructure with respect to the scour protection measure along a river reach has become a more immediate topic for river engineering society. Although numerous studies have been conducted to suggest pier scour estimation formulas, understanding of turbulence characteristics which is dominant driver of sediment transport around a pier foundation is still questionable. Thus, to understand near bed turbulence characteristics and resulting sediment transport around a pier, hydraulic laboratory experiments were conducted in a prismatic rectangular flume using scale-down bridge pier models. Three-dimensional velocities and turbulent intensities before and after scour were measured with Acoustic Doppler Velocimeter (ADV), and the results were compared/analyzed using the best available tools and current knowledge gained from recent studies. The results show that the mean flow variable is not enough to explain complex turbulent flow field around the pier leading to the maximum scour because of unsteady flows. Furthermore, results of quadrant analysis of velocity measurements just upstream of the pier in the horseshoe vortex region show significant differences before and after scour.

scholarly journals Effectiveness of combinations of raft foundation with aprons as a protection measure against bridge pier scour

Sadhana ◽  
2018 ◽  
Vol 43 (2) ◽  
Author(s):  
B A Vijayasree ◽  
T I Eldho ◽  
B S Mazumder ◽  
B V S Viswanadham
Keyword(s):  
Bridge Pier ◽  
Protection Measure ◽  
Pier Scour ◽  
Raft Foundation ◽  
Bridge Pier Scour

Bridge pier scour hazards assessment using smart-spheres

2020 ◽  
Author(s):  
Alex Corrigan ◽  
Hassan Elmubarak ◽  
Yi Xu ◽  
Panagiotis Michalis ◽  
Manousos Valyrakis
Keyword(s):  
Sediment Transport ◽  
Turbulent Flows ◽  
River Flow ◽  
Fuzzy Inference ◽  
Weather Conditions ◽  
Bridge Pier ◽  
Bridge Scour ◽  
Pier Scour ◽  
International Conference ◽  
Bridge Pier Scour

<p>Under climate change, shifting  weather conditions, (both in terms of increasing frequency and intensifying magnitude) result in increasing occurrence of catastrophic failures of the constantly exposed and ageing infrastructure, across the world. Energetic flow events, advected past hydraulic infrastructure (such as bridge piers and abutments), may lead to scour [1, 2, 3], which is the primary cause of bridge collapses, resulting in high socio-economical costs, including loss of life.</p><p>This research aims to demonstrate the use of a novel monitoring device for the assessment of scour initiated by turbulent flows. This is pursued via the use of a miniaturized instrumented particle, namely “smart-sphere”, to record directly the frequency of entrainment from its downstream placement a model bridge pier at the Water Engineering lab of the University of Glasgow [4, 5, 6]. The change in entrainment frequencies is used as a metric to assess the increasing risk to scour, with increasing flow conditions, recorded acoustic Doppler velocimetry (ADV). The utility of the method as well as the potential use of the acquired data for prediction of bridge pier scour is presented and the tool as well is discussed with the potential for use to an appropriate field site [7, 8, 9].</p><p> </p><p>Acknowledgments</p><p>This research project has been supported by Transport Scotland, under the 2019/20 Innovation Fund and the Student research award.</p><p> </p><p>References</p><p>[1] Pähtz, Th., Clark, A., Duran, O., Valyrakis, M. 2019. The physics of sediment transport initiation, cessation and entrainment across aeolian and fluvial environments, Reviews of Gephysics, https://doi.org/10.1029/2019RG000679.</p><p>[2] Yagci, O., Celik, F., Kitsikoudis, V., Kirca, O., Hodoglu, C., Valyrakis, M., Duran, Z., Kaya S. 2016. Scour patterns around individual vegetation elements, Advances in Water Resources, 97, pp 251-265, doi: 10.1016/j.advwatres.2016.10.002.</p><p>[3] Michalis, P., Saafi, M. and M.D. Judd. (2012) Integrated Wireless Sensing Technology for Surveillance and Monitoring of Bridge Scour. Proceedings of the 6th International Conference on Scour and Erosion, France, Paris, pp. 395-402.</p><p>[4] Valyrakis, M. & Pavlovskis, E. 2014. "Smart pebble” design for environmental monitoring applications, In Proceedings of the 11th International Conference on Hydroinformatics, Hamburg, Germany.</p><p>[5] Valyrakis M., A. Alexakis. 2016. Development of a “smart-pebble” for tracking sediment transport. International Conference on Fluvial Hydraulics River Flow 2016, St. Liouis, MO, 8p.</p><p>[6] Valyrakis, M., Farhadi, H. 2017. Investigating coarse sediment particles transport using PTV and “smart-pebbles” instrumented with inertial sensors, EGU General Assembly 2017, Vienna, Austria, 23-28 April 2017, id. 9980.</p><p>[7] Valyrakis, M., Diplas, P., Dancey, C.L. 2011. Prediction of coarse particle movement with adaptive neuro-fuzzy inference systems, Hydrological Processes, 25 (22). pp. 3513-3524. ISSN 0885-6087, doi:10.1002/hyp.8228.</p><p>[8] Valyrakis, M., Michalis, P., Zhang, H. 2015a. A new system for bridge scour monitoring and prediction. Proceedings of the 36th IAHR World Congress, The Hague, the Netherlands, pp. 1-4.</p>

BRIDGE PIER SCOUR: A REVIEW OF PROCESSES, MEASUREMENTS AND ESTIMATES

2012 ◽  
Vol 11 (5) ◽  
pp. 975-989 ◽  
Author(s):  
Luigia Brandimarte ◽  
Paolo Paron ◽  
Giuliano Di Baldassarre
Keyword(s):  
Bridge Pier ◽  
Pier Scour ◽  
Bridge Pier Scour

scholarly journals Modeling of solid sediment transport in mountain rivers

2020 ◽  
Vol 175 ◽  
pp. 12002 ◽  
Author(s):  
Issam Boukhanef ◽  
Anna Khadzhidi ◽  
Lyudmila Kravchenko ◽  
Zeroual Ayoub ◽  
Kastali Abdennour
Keyword(s):  
Sediment Transport ◽  
Fine Particles ◽  
Agricultural Soils ◽  
Suspended Sediments ◽  
High Water ◽  
The Other ◽  
Concentration Data ◽  
Solid Transport ◽  
One Year ◽  
The One

In Algeria, the problems of erosion and sediment transport are critical, since they have the most dramatic consequences of the degradation of agricultural soils on the one hand and the siltation of the dam on the other .The sediment transport in the Algerian basins is very important especially during the periods of floods, It is in this sense that this study, which consists of estimating the sediment transport in suspension and determining the models of relation linking the liquid discharge and the sediment discharge in order to estimate the solid transport in the absence of suspended sediments concentration data at the Sidi Akkacha station at the outlet of the basin of Oued Allala which is subject to a high water erosion, it degrades from one year to the other under the effect of this phenomenon especially during the floods which drain high amounts of fine particles exceeding in general, the concentration of 150 g/l, the results obtained from the application of the models are very encouraging since the correlation between liquid and solid discharge exceeds 80 %.

Mean flow and turbulence characteristics of a full-scale spiral corrugated culvert with implications for fish passage

2007 ◽  
Vol 30 (4) ◽  
pp. 333-340 ◽  
Author(s):  
Marshall C. Richmond ◽  
Zhiqun Deng ◽  
Gregory R. Guensch ◽  
Hans Tritico ◽  
Walter H. Pearson
Keyword(s):  
Fish Passage ◽  
Full Scale ◽  
Mean Flow ◽  
Turbulence Characteristics

Socio-Emotional and Academic Learning Before and After COVID-19 School Closures: Evidence from Ethiopia

2021 ◽  
Author(s):  
Stephen Bayley ◽  
Darge Wole Meshesha ◽  
Paul Ramchandani ◽  
Pauline Rose ◽  
Tassew Woldehanna ◽  
...  
Keyword(s):  
Mental Health ◽  
Social Skills ◽  
Emotional Regulation ◽  
Current Knowledge ◽  
Strong Relationship ◽  
Academic Learning ◽  
School Closures ◽  
Health And Wellbeing ◽  
Before And After ◽  
Children's Social Skills

This paper presents the findings of research undertaken in Ethiopia to examine the effects of COVID-19 school closures on children’s holistic learning, including both socio-emotional and academic learning. It draws on data collected in 2019 (prior to the pandemic) and 2021 (after schools reopened) to compare primary pupils’ learning before and after the school closures. In particular, the study adapts self-reporting scales that have been used in related contexts to measure Grade 3 and 6 children’s social skills, self-efficacy, emotional regulation and mental health and wellbeing, along with literacy and numeracy. Lesson observations were also undertaken to explore teachers’ behaviours to foster socio-emotional learning (SEL) in the classroom. The findings advance current knowledge in several respects. First, they quantify the decline in Ethiopian pupils’ social skills over the period of the school closures. Second, they identify a significant and strong relationship between learners’ social skills and their numeracy, even after taking other factors into account. Third, they reveal a significant association between children’s social skills and their mental health and wellbeing, highlighting the importance of interpersonal interactions to safeguard children’s holistic welfare. The paper concludes by proposing a model for understanding the relationship between learners’ SEL and academic outcomes, and with recommendations for education planning and practice, in Ethiopia and elsewhere.

Bridge Pier Scour Assessment for the Northumberland Strait Crossing

1997 ◽  
Author(s):  
C.D. Anglin ◽  
R.B. Nairn ◽  
A.M. Cornett ◽  
L. Dunaszegi ◽  
J. Turnham ◽  
...  
Keyword(s):  
Bridge Pier ◽  
Pier Scour ◽  
Bridge Pier Scour

Probablistic Bridge Pier Scour Factors

2014 ◽  
Author(s):  
Peggy Johnson ◽  
Paul Clopper ◽  
Lyle Zevenbergen
Keyword(s):  
Bridge Pier ◽  
Pier Scour ◽  
Bridge Pier Scour

scholarly journals Discharge and Sediment Transport in a River Basin. Assessment Before and After the Construction of a Dam at the Upper Basin Boundary

2021 ◽  
Author(s):  
George Paschalidis ◽  
Ilias IIordanidis ◽  
Petros Anagnostopoulos
Keyword(s):  
Sediment Transport ◽  
Meteorological Data ◽  
Climatic Data ◽  
Northern Greece ◽  
Basin Boundary ◽  
Software Packages ◽  
Before And After ◽  
The Mean ◽  
Gis Interface ◽  
Good Agreement

Abstract The purpose of this study is the evaluation of runoff and sediment transport in the basin of the Nestos River (Northern Greece) downstream of the dam of Platanovrisi, constructed in 1998. The model used for the simulation was AGNPS, which is based on the Revised Universal Soil Loss Equation (RUSLE), combined with a GIS interface. Two different simulations were conducted, one for the years 1980-1990 and another for the period 2006-2030, before and after the construction of the dam respectively. For the simulation for the period 1980-1990 existing meteorological data were employed, and the results were in good agreement with those of a different study (Hrissanthou, 2002). The simulation for the period 2006-2030 was based on rainfall and climatic data generated from the software packages GlimClim and ClimGen. The mean runoff was by 5% lower and the mean annual sediment yield by 20% lower than the corresponding values for the period 1980-1990.

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