Experimental Investigation of Bedload Sediment Transport and Bed Evolution in Double-Peaked Hydrograph

Le Wang, Alan Cuthbertson, Deyu Zhong, Gareth Pender, Zhixian Cao

Research output: Contribution to conferencePaper

Abstract

In natural rivers, significant bedload transport and variability in sediment bed geomorphology is generally observed to occur under unsteady flows, especially during flood events. In this study, a double-peaked hydrograph event, consisting of two identical and consecutive flood waves (i.e. sub-hydrographs), was performed in a large titling flume to investigate the behavior of bedload transport and response of sediment bed change within both uniform and fine-graded sediment beds, respectively. The results indicate that the total bedload transport rates for both uniform and fine-grained sediment beds tend to be reduced during the second sub-hydrograph, in comparison to the first sub-hydrograph, with more significant reductions observed to occur during the rising limb compared to the falling limb. In terms of fractional transport rates for the fine-graded sediment, the results also show that the bedload transport rates for the coarsest fraction are most significantly reduced in the second sub-hydrograph, compared to the first, during the rising limb. A similar overall trend is also shown for the corresponding fine and medium sediment fractions. In terms of the bed evolution over the duration of the double-peaked hydrograph, detailed measurement of bed surface elevation within both uniform and graded sediment beds runs reveal that the well-defined alternate bars are generated in uniform sediment bed, while only slight variations in elevation are found to occur in the fine-graded sediment bed with no indication of the generation of bed forms.
Original languageEnglish
Pages1-10
Number of pages10
Publication statusPublished - Aug 2017
Event37th IAHR World Congress - Putra World Trade Centre, Kuala Lumpur, Malaysia
Duration: 13 Aug 201718 Aug 2017
http://www.iahrworldcongress.org/index.php

Conference

Conference37th IAHR World Congress
CountryMalaysia
CityKuala Lumpur
Period13/08/1718/08/17
Internet address

Fingerprint

bedload
hydrograph
sediment transport
sediment
limb
flood wave
unsteady flow
fine grained sediment
bedform
geomorphology
river
rate

Keywords

  • Bedload transport
  • Double-peaked hydrograph
  • Bed elevation
  • Uniform and graded sediments
  • Flume experiments

Cite this

Wang, L., Cuthbertson, A., Zhong, D., Pender, G., & Cao, Z. (2017). Experimental Investigation of Bedload Sediment Transport and Bed Evolution in Double-Peaked Hydrograph. 1-10. Paper presented at 37th IAHR World Congress, Kuala Lumpur, Malaysia.
Wang, Le ; Cuthbertson, Alan ; Zhong, Deyu ; Pender, Gareth ; Cao, Zhixian. / Experimental Investigation of Bedload Sediment Transport and Bed Evolution in Double-Peaked Hydrograph. Paper presented at 37th IAHR World Congress, Kuala Lumpur, Malaysia.10 p.
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abstract = "In natural rivers, significant bedload transport and variability in sediment bed geomorphology is generally observed to occur under unsteady flows, especially during flood events. In this study, a double-peaked hydrograph event, consisting of two identical and consecutive flood waves (i.e. sub-hydrographs), was performed in a large titling flume to investigate the behavior of bedload transport and response of sediment bed change within both uniform and fine-graded sediment beds, respectively. The results indicate that the total bedload transport rates for both uniform and fine-grained sediment beds tend to be reduced during the second sub-hydrograph, in comparison to the first sub-hydrograph, with more significant reductions observed to occur during the rising limb compared to the falling limb. In terms of fractional transport rates for the fine-graded sediment, the results also show that the bedload transport rates for the coarsest fraction are most significantly reduced in the second sub-hydrograph, compared to the first, during the rising limb. A similar overall trend is also shown for the corresponding fine and medium sediment fractions. In terms of the bed evolution over the duration of the double-peaked hydrograph, detailed measurement of bed surface elevation within both uniform and graded sediment beds runs reveal that the well-defined alternate bars are generated in uniform sediment bed, while only slight variations in elevation are found to occur in the fine-graded sediment bed with no indication of the generation of bed forms.",
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Wang, L, Cuthbertson, A, Zhong, D, Pender, G & Cao, Z 2017, 'Experimental Investigation of Bedload Sediment Transport and Bed Evolution in Double-Peaked Hydrograph' Paper presented at 37th IAHR World Congress, Kuala Lumpur, Malaysia, 13/08/17 - 18/08/17, pp. 1-10.

Experimental Investigation of Bedload Sediment Transport and Bed Evolution in Double-Peaked Hydrograph. / Wang, Le; Cuthbertson, Alan; Zhong, Deyu; Pender, Gareth; Cao, Zhixian.

2017. 1-10 Paper presented at 37th IAHR World Congress, Kuala Lumpur, Malaysia.

Research output: Contribution to conferencePaper

TY - CONF

T1 - Experimental Investigation of Bedload Sediment Transport and Bed Evolution in Double-Peaked Hydrograph

AU - Wang, Le

AU - Cuthbertson, Alan

AU - Zhong, Deyu

AU - Pender, Gareth

AU - Cao, Zhixian

PY - 2017/8

Y1 - 2017/8

N2 - In natural rivers, significant bedload transport and variability in sediment bed geomorphology is generally observed to occur under unsteady flows, especially during flood events. In this study, a double-peaked hydrograph event, consisting of two identical and consecutive flood waves (i.e. sub-hydrographs), was performed in a large titling flume to investigate the behavior of bedload transport and response of sediment bed change within both uniform and fine-graded sediment beds, respectively. The results indicate that the total bedload transport rates for both uniform and fine-grained sediment beds tend to be reduced during the second sub-hydrograph, in comparison to the first sub-hydrograph, with more significant reductions observed to occur during the rising limb compared to the falling limb. In terms of fractional transport rates for the fine-graded sediment, the results also show that the bedload transport rates for the coarsest fraction are most significantly reduced in the second sub-hydrograph, compared to the first, during the rising limb. A similar overall trend is also shown for the corresponding fine and medium sediment fractions. In terms of the bed evolution over the duration of the double-peaked hydrograph, detailed measurement of bed surface elevation within both uniform and graded sediment beds runs reveal that the well-defined alternate bars are generated in uniform sediment bed, while only slight variations in elevation are found to occur in the fine-graded sediment bed with no indication of the generation of bed forms.

AB - In natural rivers, significant bedload transport and variability in sediment bed geomorphology is generally observed to occur under unsteady flows, especially during flood events. In this study, a double-peaked hydrograph event, consisting of two identical and consecutive flood waves (i.e. sub-hydrographs), was performed in a large titling flume to investigate the behavior of bedload transport and response of sediment bed change within both uniform and fine-graded sediment beds, respectively. The results indicate that the total bedload transport rates for both uniform and fine-grained sediment beds tend to be reduced during the second sub-hydrograph, in comparison to the first sub-hydrograph, with more significant reductions observed to occur during the rising limb compared to the falling limb. In terms of fractional transport rates for the fine-graded sediment, the results also show that the bedload transport rates for the coarsest fraction are most significantly reduced in the second sub-hydrograph, compared to the first, during the rising limb. A similar overall trend is also shown for the corresponding fine and medium sediment fractions. In terms of the bed evolution over the duration of the double-peaked hydrograph, detailed measurement of bed surface elevation within both uniform and graded sediment beds runs reveal that the well-defined alternate bars are generated in uniform sediment bed, while only slight variations in elevation are found to occur in the fine-graded sediment bed with no indication of the generation of bed forms.

KW - Bedload transport

KW - Double-peaked hydrograph

KW - Bed elevation

KW - Uniform and graded sediments

KW - Flume experiments

UR - http://www.iahrworldcongress.org/index.php/programme/presentation-schedule

UR - http://www.iahrworldcongress.org/index.php/submission/congress-proceedings

M3 - Paper

SP - 1

EP - 10

ER -

Wang L, Cuthbertson A, Zhong D, Pender G, Cao Z. Experimental Investigation of Bedload Sediment Transport and Bed Evolution in Double-Peaked Hydrograph. 2017. Paper presented at 37th IAHR World Congress, Kuala Lumpur, Malaysia.