Application Of Fuzzy Logic In The Assessment Of River Flow Characteristics At The Pier Scour

2012 ◽  
Author(s):  
Ponselvi Jeevaragagam ◽  
Ahmad Khairi ◽  
Tahir Ahmad
Keyword(s):  
Fuzzy Logic ◽  
River Flow ◽  
Flow Characteristics ◽  
Uncertainty Modeling ◽  
Bridge Scour ◽  
Flow Area ◽  
Pier Scour ◽  
Bridge Model ◽  
Prevention Method ◽  
Fuzzy Logic Technique

Pada masa kini, tiada pembangunan teknik yang rasional untuk seseorang jurutera jambatan mengikutinya sebagai panduan apabila menilai kesan kerokan disebabkan aliran sungai pada penapak tiang jambatan. Biasanya penilaian kerokan pada jambatan adalah berdasarkan prosedur subjektif yang mana kosnya adalah mahal, pengambilan masa, ketidakpastian dan mempunyai bias oleh seseorang individu. Oleh itu, tujuan penyelidikan ini adalah untuk memperkenalkan teknik logik kabur dalam menilai sifat-sifat aliran sungai pada hulu jambatan (keadalaman aliran (Y1); kadaralir (Q1); kelajuan (V1); dan luas aliran (A1)), yang mana menyebabkan kerokan pada penapak tiang jambatan. Dalam mencapai objektif kajian ini, satu contoh masalah telah diperkenalkan untuk menggambarkan penggunaan metodologi terhadap hipotesis model jambatan yang merentangi Sungai Cherul di Ban Ho, Terengganu, Malaysia. Daripada penyelidikan ini, tahap keadaan kerokan pada penapak tiang boleh ditentukan dan maklumat ini dapat digunakan kelak oleh seseorang jurutera jambatan dalam menyediakan kaedah kawalan yang sesuai. Seterusnya, kaedah ini boleh membantu jurutera jambatan untuk membuat keputusan yang lebih rasional semasa menjalankan program pembaikan jambatan berdasarkan data pengawasan jambatan. Kata kunci: Penilaian kerokan jambatan; keadaan kerokan tiang jambatan; kesan aliran sungai; model kata putus seragam; permodelan ketidakpastian Currently; there is no well-established technique for a bridge inspector to follow when assessing the river flow effect to the scour depth at a bridge pier. The assessment of a bridge scour is normally based on subjective procedures that are costly, time consuming, uncertain and has a personal bias. Therefore, the purpose of this research is to propose the fuzzy logic technique in assessing the river flow characteristics at the upstream of the bridge (flow depth (Y1); discharge (Q1); velocity (V1); and flow area (A1)), which are resulted scouring at the pier foundation. In order to achieve the objective of this research, an example problem is presented to illustrate the use of the proposed methodology on a hypothetical bridge model across Cherul River at Ban Ho, Terengganu, Malaysia. From the research, the severity of scour condition at the pier foundation can be determined and this information will be useful for a bridge engineer to provide the relevant countermeasure or prevention method. Finally; this approach can assist a bridge engineer in making a rational decision for carrying out the bridge maintenance programme based on data taken from regular bridge inspection Key words: Bridge scour assessment; pier scour condition; river flow effects; uniform decision-making model; uncertainty modeling

scholarly journals Using Bayesian networks for the assessment of underwater scour for road and railway bridges

2020 ◽  
pp. 147592172095657
Author(s):  
Andrea Maroni ◽  
Enrico Tubaldi ◽  
Dimitri V Val ◽  
Hazel McDonald ◽  
Daniele Zonta
Keyword(s):  
Bayesian Networks ◽  
Bayesian Network ◽  
River Flow ◽  
Flow Characteristics ◽  
The United States ◽  
Monitoring Systems ◽  
Scour Depth ◽  
Bridge Scour ◽  
Railway Bridges ◽  
Scour Monitoring

Flood-induced scour is among the most common external causes of bridge failures worldwide. In the United States, scour is the cause of 22 bridges fails every year, whereas in the UK, it contributed significantly to the 138 collapses of bridges in the last century. Scour assessments are currently based on visual inspections, which are time-consuming and expensive. Nowadays, sensor and communication technologies offer the possibility to assess in real time the scour depth at critical bridge locations; yet, monitoring an entire infrastructure network is not economically feasible. A way to overcome this limitation is to instal scour monitoring systems at critical bridge locations, and then extend the piece of information gained to the other assets exploiting the correlations present in the system. In this article, we propose a scour hazard model for road and railway bridge scour management that utilises information from a limited number of scour monitoring systems to achieve a more confined estimate of the scour risk for a bridge network. A Bayesian network is used to describe the conditional dependencies among the involved random variables and to update the scour depth distribution using data from monitoring of scour and river flow characteristics. This study constitutes the first application of Bayesian networks to bridge scour risk assessment. The proposed probabilistic framework is applied to a case study consisting of several road bridges in Scotland. The bridges cross the same river, and only one of them is instrumented with a scour monitoring system. It is demonstrated how the Bayesian network approach allows to significantly reduce the uncertainty in the scour depth at unmonitored bridges.

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>

scholarly journals Transformation of the Flow Regime of a Large Allochthonous River in Central Europe—An Example of the Vistula River in Poland

Water ◽  
2020 ◽  
Vol 12 (2) ◽  
pp. 507 ◽  
Author(s):  
Dariusz Wrzesiński ◽  
Leszek Sobkowiak
Keyword(s):  
Flow Regime ◽  
Annual Cycle ◽  
River Flow ◽  
Hydrological Cycle ◽  
Temporal Structure ◽  
Flow Characteristics ◽  
Point Of View ◽  
Theoretical Point ◽  
Vistula River ◽  
Basin Water

Identification of river flow regime and its possible changes caused by natural factors or human activity is one of major issues in modern hydrology. In such studies different approaches and different indicators can be used. The aim of this study is to determine changes in flow regime of the largest river in Poland—the Vistula, using new, more objectified coefficients and indices, based on data recorded in 22 gauges on the Vistula mainstream and 38 gauges on its tributaries in the multi-year period 1971–2010. The paper consists of three main parts: in the first part, in order to recognize changes in the flow regime characteristics along the Vistula, data from gauges located on the river mainstream were analyzed with the help of the theory of entropy. In the second part gauging stations on the Vistula mainstream and its tributaries were grouped; values of the newly introduced pentadic Pardé’s coefficient of flow (discharge) (PPC) were taken as the grouping criterion. In the third part of the study a novel method of determining river regime characteristics was applied: through the recognition of the temporal structure of hydrological phenomena and their changes in the annual cycle sequences of hydrological periods (characteristic phases of the hydrological cycle) on the Vistula River mainstream and its tributaries were identified and their occurrence in the yearly cycle was discussed. Based on the detected changes of the 73-pentad Pardé’s coefficients of flow four main types of rivers were distinguished. Transformation of the flow regime was reflected in the identified different sequences of hydrological periods in the average annual cycle. It was found that while transformation of the Vistula River regime occurred along its whole course, the most frequent changes were detected in its upper, mountainous reaches, under the influence of the flow characteristics of its tributaries. This allowed the Vistula to be considered the allochthonous river. These findings are interesting not only from a theoretical point of view, but they also can be valuable to stakeholders in the field of the Vistula River basin water management and hydrological forecasting, including flood protection, which has recently become a matter of growing concern due to the observed effects of climate change and human impact.

Cholera Disease Detection using Fuzzy Logic Technique

2021 ◽  
Author(s):  
Swati Jayade ◽  
D. T. Ingole ◽  
Manik D. Ingole ◽  
Aditya Tohare
Keyword(s):  
Fuzzy Logic ◽  
Disease Detection ◽  
Fuzzy Logic Technique

scholarly journals How will climate change modify river flow regimes in Europe?

2013 ◽  
Vol 17 (1) ◽  
pp. 325-339 ◽  
Author(s):  
C. Schneider ◽  
C. L. R. Laizé ◽  
M. C. Acreman ◽  
M. Flörke
Keyword(s):  
Climate Change ◽  
River Flow ◽  
Anthropogenic Impacts ◽  
Flow Characteristics ◽  
Flow Regimes ◽  
Temperate Climate ◽  
Climate Zone ◽  
Natural Flow ◽  
The Mediterranean ◽  
Boreal Climate

Abstract. Worldwide, flow regimes are being modified by various anthropogenic impacts and climate change induces an additional risk. Rising temperatures, declining snow cover and changing precipitation patterns will interact differently at different locations. Consequently, in distinct climate zones, unequal consequences can be expected in matters of water stress, flood risk, water quality, and food security. In particular, river ecosystems and their vital ecosystem services will be compromised as their species richness and composition have evolved over long time under natural flow conditions. This study aims at evaluating the exclusive impacts of climate change on river flow regimes in Europe. Various flow characteristics are taken into consideration and diverse dynamics are identified for each distinct climate zone in Europe. In order to simulate present-day natural flow regimes and future flow regimes under climate change, the global hydrology model WaterGAP3 is applied. All calculations for current and future conditions (2050s) are carried out on a 5' × 5' European grid. To address uncertainty, bias-corrected climate forcing data of three different global climate models are used to drive WaterGAP3. Finally, the hydrological alterations of different flow characteristics are quantified by the Indicators of Hydrological Alteration approach. Results of our analysis indicate that on the European scale, climate change can be expected to modify flow regimes remarkably. This is especially the case in the Mediterranean (due to drier conditions with reduced precipitation across the year) and in the boreal climate zone (due to reduced snowmelt, increased precipitation, and strong temperature rises). In the temperate climate zone, impacts increase from oceanic to continental. Regarding single flow characteristics, strongest impacts on timing were found for the boreal climate zone. This applies for both high and low flows. Flow magnitudes, in turn, will be predominantly altered in the Mediterranean but also in the Northern climates. At the end of this study, typical future flow regimes under climate change are illustrated for each climate zone.

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