TY  - JOUR
AU  - Ebrahimi, Mohsen
AU  - Kripakaran, Prakash
AU  - Prodanović, Dušan
AU  - Kahraman, Recep
AU  - Riella, Matthew
AU  - Tabor, Gavin
AU  - Arthur, Scott
AU  - Đorđević, Slobodan
PY  - 2018
UR  - https://grafar.grf.bg.ac.rs/handle/123456789/985
AB  - Previous experimental research on the effects of debris on pier scour has focused primarily on circular and rectangular piers with debris present just under flow free surface. Debris-induced scour around sharp-nose piers, which are typical of masonry bridge piers, and the effect of debris elevation on pier scour have seldom been studied before. This paper aims to fill this knowledge gap. It presents results from flume experiments investigating scour around a sharp-nose pier under shallow flow conditions with angle of attack relative to the pier being zero. Uniform sand is used as bed material. Debris is modeled as stationary and extending only upstream of the pier. Three simplified debris geometries (cylinder, half-pyramid, and plate) are studied. Results show that scour depth decreases as debris gets closer to the bed with maximum scour depth occurring when debris is located just under the flow free surface. Interestingly, scour depths produced by debris in shallow flow are observed to be comparable to those produced by deep flow in the absence of debris. This finding highlights the importance of monitoring debris accumulation at bridges in nonflood conditions. Results also show that the volume of the scour hole around a pier increases quadratically with maximum scour depth. This information is useful for postflood scour remedial works. Lastly, the collected laboratory measurements are used to compare four popular equations for scour estimation on their ability to predict debris-induced scour. The Colorado State University (CSU) equation is found to offer the most accurate predictions.
PB  - American Society of Civil Engineers (ASCE)
T2  - Journal of Hydraulic Engineering
T1  - Experimental Study on Scour at a Sharp-Nose Bridge Pier with Debris Blockage
IS  - 12
VL  - 144
DO  - 10.1061/(ASCE)HY.1943-7900.0001516
ER  - 

@article{
author = "Ebrahimi, Mohsen and Kripakaran, Prakash and Prodanović, Dušan and Kahraman, Recep and Riella, Matthew and Tabor, Gavin and Arthur, Scott and Đorđević, Slobodan",
year = "2018",
abstract = "Previous experimental research on the effects of debris on pier scour has focused primarily on circular and rectangular piers with debris present just under flow free surface. Debris-induced scour around sharp-nose piers, which are typical of masonry bridge piers, and the effect of debris elevation on pier scour have seldom been studied before. This paper aims to fill this knowledge gap. It presents results from flume experiments investigating scour around a sharp-nose pier under shallow flow conditions with angle of attack relative to the pier being zero. Uniform sand is used as bed material. Debris is modeled as stationary and extending only upstream of the pier. Three simplified debris geometries (cylinder, half-pyramid, and plate) are studied. Results show that scour depth decreases as debris gets closer to the bed with maximum scour depth occurring when debris is located just under the flow free surface. Interestingly, scour depths produced by debris in shallow flow are observed to be comparable to those produced by deep flow in the absence of debris. This finding highlights the importance of monitoring debris accumulation at bridges in nonflood conditions. Results also show that the volume of the scour hole around a pier increases quadratically with maximum scour depth. This information is useful for postflood scour remedial works. Lastly, the collected laboratory measurements are used to compare four popular equations for scour estimation on their ability to predict debris-induced scour. The Colorado State University (CSU) equation is found to offer the most accurate predictions.",
publisher = "American Society of Civil Engineers (ASCE)",
journal = "Journal of Hydraulic Engineering",
title = "Experimental Study on Scour at a Sharp-Nose Bridge Pier with Debris Blockage",
number = "12",
volume = "144",
doi = "10.1061/(ASCE)HY.1943-7900.0001516"
}

Ebrahimi, M., Kripakaran, P., Prodanović, D., Kahraman, R., Riella, M., Tabor, G., Arthur, S.,& Đorđević, S.. (2018). Experimental Study on Scour at a Sharp-Nose Bridge Pier with Debris Blockage. in Journal of Hydraulic Engineering
American Society of Civil Engineers (ASCE)., 144(12).
https://doi.org/10.1061/(ASCE)HY.1943-7900.0001516

Ebrahimi M, Kripakaran P, Prodanović D, Kahraman R, Riella M, Tabor G, Arthur S, Đorđević S. Experimental Study on Scour at a Sharp-Nose Bridge Pier with Debris Blockage. in Journal of Hydraulic Engineering. 2018;144(12).
doi:10.1061/(ASCE)HY.1943-7900.0001516 .

Ebrahimi, Mohsen, Kripakaran, Prakash, Prodanović, Dušan, Kahraman, Recep, Riella, Matthew, Tabor, Gavin, Arthur, Scott, Đorđević, Slobodan, "Experimental Study on Scour at a Sharp-Nose Bridge Pier with Debris Blockage" in Journal of Hydraulic Engineering, 144, no. 12 (2018),
https://doi.org/10.1061/(ASCE)HY.1943-7900.0001516 . .

TY  - CONF
AU  - Ebrahimi, Mohsen
AU  - Kahraman, Recep
AU  - Riella, M.
AU  - Kripakaran, Prakash
AU  - Đorđević, Slobodan
AU  - Tabor, Gavin
AU  - Prodanović, Dušan
AU  - Arthur, Scott
PY  - 2018
UR  - https://grafar.grf.bg.ac.rs/handle/123456789/929
AB  - This paper presents two experiments, carried out in a 605mm-wide flume, to investigate scour and hydrodynamic pressure on a scaled model of a single span arch bridge. The geometry of the bridge model is scaled down according to a prototype bridge, with hydraulic conditions of the experiments representing a small river. Measurements showed that vertical-contraction scour by the arch bridge is higher than that of flat-deck bridges. Effect of a single cylindrical debris on scour was also evaluated and found to be negligible at the considered flow depth. Temporal variation of hydrodynamic pressure with scour evolution was also measured. It was found that temporal evolution of scour can reduce hydrodynamic pressure significantly at the initial base of the abutment at downstream face of the bridge, which can Erode mortar from the masonry composition of an arch bridge.
PB  - Utah State University
C3  - 7th IAHR International Symposium on Hydraulic Structures, ISHS 2018
T1  - Experimental investigation of scour and pressures on a single span arch bridge under inundation
EP  - 722
SP  - 715
DO  - 10.15142/T33D25
ER  - 

@conference{
author = "Ebrahimi, Mohsen and Kahraman, Recep and Riella, M. and Kripakaran, Prakash and Đorđević, Slobodan and Tabor, Gavin and Prodanović, Dušan and Arthur, Scott",
year = "2018",
abstract = "This paper presents two experiments, carried out in a 605mm-wide flume, to investigate scour and hydrodynamic pressure on a scaled model of a single span arch bridge. The geometry of the bridge model is scaled down according to a prototype bridge, with hydraulic conditions of the experiments representing a small river. Measurements showed that vertical-contraction scour by the arch bridge is higher than that of flat-deck bridges. Effect of a single cylindrical debris on scour was also evaluated and found to be negligible at the considered flow depth. Temporal variation of hydrodynamic pressure with scour evolution was also measured. It was found that temporal evolution of scour can reduce hydrodynamic pressure significantly at the initial base of the abutment at downstream face of the bridge, which can Erode mortar from the masonry composition of an arch bridge.",
publisher = "Utah State University",
journal = "7th IAHR International Symposium on Hydraulic Structures, ISHS 2018",
title = "Experimental investigation of scour and pressures on a single span arch bridge under inundation",
pages = "722-715",
doi = "10.15142/T33D25"
}

Ebrahimi, M., Kahraman, R., Riella, M., Kripakaran, P., Đorđević, S., Tabor, G., Prodanović, D.,& Arthur, S.. (2018). Experimental investigation of scour and pressures on a single span arch bridge under inundation. in 7th IAHR International Symposium on Hydraulic Structures, ISHS 2018
Utah State University., 715-722.
https://doi.org/10.15142/T33D25

Ebrahimi M, Kahraman R, Riella M, Kripakaran P, Đorđević S, Tabor G, Prodanović D, Arthur S. Experimental investigation of scour and pressures on a single span arch bridge under inundation. in 7th IAHR International Symposium on Hydraulic Structures, ISHS 2018. 2018;:715-722.
doi:10.15142/T33D25 .

Ebrahimi, Mohsen, Kahraman, Recep, Riella, M., Kripakaran, Prakash, Đorđević, Slobodan, Tabor, Gavin, Prodanović, Dušan, Arthur, Scott, "Experimental investigation of scour and pressures on a single span arch bridge under inundation" in 7th IAHR International Symposium on Hydraulic Structures, ISHS 2018 (2018):715-722,
https://doi.org/10.15142/T33D25 . .

TY  - CONF
AU  - Ebrahimi, Mohsen
AU  - Kripakaran, Prakash
AU  - Đorđević, Slobodan
AU  - Tabor, Gavin
AU  - Kahraman, Recep
AU  - Prodanović, Dušan
AU  - Arthur, Scott
PY  - 2016
UR  - https://grafar.grf.bg.ac.rs/handle/123456789/735
AB  - This paper describes the preliminary stage of an ongoing project investigating the hydrodynamic effects of debris blockage at masonry bridges. Debris blockage is cited as one of the primary causes of bridge failures in the UK and around the world. Masonry bridges, many of which are valuable historical assets, are particularly vulnerable to debris blockage due to their short spans and low clearance. This paper presents work done as part of the first phase of the project involving experimental research to understand the scientific relationships between debris characteristics and flow conditions. The study, being carried out at Centre for Water Systems at University of Exeter, utilizes a 0.6 m-wide and 10 m-long flume to run hydraulic experiments in order to characterize the impact of debris blockage on flow hydrodynamics, scour, and hydrodynamic pressures and forces at masonry bridges. This paper outlines the design of the experimental setup and the reasoning behind the choices for preliminary experimental parameters. The experiments are to include testing of bridge models and various 3D-printed debris shapes under realistic flow conditions. Geometry of the bridge and debris models are kept approximately similar to prototype conditions, with hydraulic conditions of the experiments designed to the degree that experimental constraints allow based on Froude similarity. Velocities, scour and hydrodynamic pressures are measured using an Acoustic Doppler Velocimeter, echo-sounding concept and pressure sensors, respectively. Preliminary results indicate that the designed experiments have the potential to enhance our understanding of the hydrodynamic effects of debris blockage.
PB  - CRC Press/Balkema
C3  - Scour and Erosion - Proceedings of the 8th International Conference on Scour and Erosion, ICSE 2016
T1  - Hydrodynamic effects of debris blockage and scour on masonry bridges: Towards experimental modelling
EP  - 750
SP  - 743
UR  - https://hdl.handle.net/21.15107/rcub_grafar_735
ER  - 

@conference{
author = "Ebrahimi, Mohsen and Kripakaran, Prakash and Đorđević, Slobodan and Tabor, Gavin and Kahraman, Recep and Prodanović, Dušan and Arthur, Scott",
year = "2016",
abstract = "This paper describes the preliminary stage of an ongoing project investigating the hydrodynamic effects of debris blockage at masonry bridges. Debris blockage is cited as one of the primary causes of bridge failures in the UK and around the world. Masonry bridges, many of which are valuable historical assets, are particularly vulnerable to debris blockage due to their short spans and low clearance. This paper presents work done as part of the first phase of the project involving experimental research to understand the scientific relationships between debris characteristics and flow conditions. The study, being carried out at Centre for Water Systems at University of Exeter, utilizes a 0.6 m-wide and 10 m-long flume to run hydraulic experiments in order to characterize the impact of debris blockage on flow hydrodynamics, scour, and hydrodynamic pressures and forces at masonry bridges. This paper outlines the design of the experimental setup and the reasoning behind the choices for preliminary experimental parameters. The experiments are to include testing of bridge models and various 3D-printed debris shapes under realistic flow conditions. Geometry of the bridge and debris models are kept approximately similar to prototype conditions, with hydraulic conditions of the experiments designed to the degree that experimental constraints allow based on Froude similarity. Velocities, scour and hydrodynamic pressures are measured using an Acoustic Doppler Velocimeter, echo-sounding concept and pressure sensors, respectively. Preliminary results indicate that the designed experiments have the potential to enhance our understanding of the hydrodynamic effects of debris blockage.",
publisher = "CRC Press/Balkema",
journal = "Scour and Erosion - Proceedings of the 8th International Conference on Scour and Erosion, ICSE 2016",
title = "Hydrodynamic effects of debris blockage and scour on masonry bridges: Towards experimental modelling",
pages = "750-743",
url = "https://hdl.handle.net/21.15107/rcub_grafar_735"
}

Ebrahimi, M., Kripakaran, P., Đorđević, S., Tabor, G., Kahraman, R., Prodanović, D.,& Arthur, S.. (2016). Hydrodynamic effects of debris blockage and scour on masonry bridges: Towards experimental modelling. in Scour and Erosion - Proceedings of the 8th International Conference on Scour and Erosion, ICSE 2016
CRC Press/Balkema., 743-750.
https://hdl.handle.net/21.15107/rcub_grafar_735

Ebrahimi M, Kripakaran P, Đorđević S, Tabor G, Kahraman R, Prodanović D, Arthur S. Hydrodynamic effects of debris blockage and scour on masonry bridges: Towards experimental modelling. in Scour and Erosion - Proceedings of the 8th International Conference on Scour and Erosion, ICSE 2016. 2016;:743-750.
https://hdl.handle.net/21.15107/rcub_grafar_735 .

Ebrahimi, Mohsen, Kripakaran, Prakash, Đorđević, Slobodan, Tabor, Gavin, Kahraman, Recep, Prodanović, Dušan, Arthur, Scott, "Hydrodynamic effects of debris blockage and scour on masonry bridges: Towards experimental modelling" in Scour and Erosion - Proceedings of the 8th International Conference on Scour and Erosion, ICSE 2016 (2016):743-750,
https://hdl.handle.net/21.15107/rcub_grafar_735 .