International Journal of Scientific & Engineering Research, Volume 5, Issue 7, July-2014 ISSN

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1 International Journal Scientific & Engineering Research Volume Issue July- ISSN 9- Estimation the quantity sediment transport upstream Al- Hafar regulator using different formulas Pr Dr Saleh I Khassaf Sahar Munder Ressen University Basrah/Faculty Engineering/Civil Department University Kufa /Faculty Engineering/Civil Department Abstract-In this research the sediments transport estimating their amount have been studied in up-stream Al- Hafar regulator on Euphrates river which is located in the south Iraq within Dhi-Qar governorate For the analysis the applicability sediment transport formulas to the study reach eight formulas were chosen for that purpose namely: -Hansen -White Abed-Al- Rahman The applications each formula was required data collected from field measurements twenty-one sections along the study reach km in order to measure the hydraulic parameters properties sediments transported Samples water sediment bed material have been taken at each section using homemade Sampler while the hydraulic parameters were measured using Acoustic Doppler Current Prile ADCP device From the analysis using statistical graphical methods the formulas -Hansen are better other formulas selected in the predicting the total sediment load in reach study which are nearly with observed quantity Finally The average predicted annual total sediment discharge has been estimated through field measurements about ton Keywords: Sediment Transport River Bed Al-Hafar regulator sediment formulas -Introduction Sedimentation in rivers estuaries coastal regions has important environmental economic influences including formation elevation changes deltas expansion alluvial channels migration rivers And the impact these deposits should be taken into account in many hydraulic engineering projects such as irrigation systems canals for navigation hydroelectric power stations ports other coastal engineering works It is therefore necessary to control sedimentation on such important projects[] Rivers channels are considered to be an important means for water supply irrigation navigation water power generation other public uses The presence movement sediment causes many problems The erosion deposition solid material the bed banks the channel increase bed deformation which in turn will reduce the depth water in some places reduce the ability the water way for navigation or hydraulic purposes However the raising the river bed by the deposited materials increases the flood range to a great extent As a result large sums money have to be spent to maintain the course the river suitable for the hydraulic requirements[] Most sediment transport equations are derived under the assumption some theoretical empirical bases These equations have a boundary condition should not be accepted as a general rule yet there is no a universal formula that can be considered suitable to be used to estimate a sediment transport rate for all rivers This reason suggests the need for additional work in this field Hence in this research an investigation was made with dual objectives testing the accuracy some the existing computational methods proposing an alternative Where no previous study by the researchers to estimate the amount sediment at the site the study - Description Al-Hafar regulator Al-Hafar regulator channel is considered as one the most important projects irrigation in the region for the large areas that benefited from it the technical applets performance It is located in Suq Al- Shuyukh areaal- Karma south-east in Dhi-Qar governorate on Euphrates River The regulator is constructed in9 it consists seven steel sliding gates in addition to the navigation lock each gate with a dimension xm The designed flood discharge the regulator is m/sec The reach study upstream the regulator with length Km It is located between longitude E '9" to E

International Journal Scientific & Engineering Research Volume Issue July- ISSN 9- '" ' 9" latitude N '" to N -Field Measurement Sediment measurement in this study involves selected twenty one

total length the reach in this study is about Km as shown in figure The measurement include discharge average velocity width cross section area for each cross section sampling the water-sediment

2 International Journal Scientific & Engineering Research Volume Issue July- ISSN 9- '" ' 9" latitude N '" to N -Field Measurement Sediment measurement in this study involves selected twenty one sections along the reach upstream Al-Hafar regulator on the Euphrates river with different distance range -m between section another as required by the nature the study area hydraulic conditions The total length the reach in this study is about Km as shown in figure The measurement include discharge average velocity width cross section area for each cross section sampling the water-sediment mixture to determine the mean suspended sediment concentration particle size distribution other physical properties the transported solids The flow depth ranged from to meters with flow ranging from to m/sec The flow velocities ranges from to m/sec the median sediment size 9 to mm for the bed material composition was observed A summary data used in the study is shows in table Table : Primary data parameter Sec No Qwm/sec 99 V m/sec d mm A m 9 B m Rh m 99 ⱱ m/sec Ws m/sec U* m/sec 9 Sec No Qwm/sec V m/sec 9 d mm A m 9 B m 9 9 Rh m 9 9 ⱱ m/sec Ws m/sec U* m/sec Sec No Qwm/sec 9 V m/sec d mm 9 Al-Hafar Regulator Fig : The positions cross-sections CS in the region study by Google Earth

3 International Journal Scientific & Engineering Research Volume Issue July- ISSN 9- A m Sec No Qw m/sec V m/sec - 9 d mm A m 9 9 B m Rh m ⱱ m/sec - - Ws m/sec 9 U* m/sec B m 9 99 Sec No Qw m/sec Rh m V m/sec 9 ⱱ m/sec Ws m/sec 9 d mm 9 U* m/sec A m 9 B m Rh m Sec No Qw m/sec V m/sec ⱱ m /sec 9 Ws m/sec 9 d mm U* m/sec A m Sec No Qw m/sec V m/sec B m 9 Rh m 9 ⱱ m/sec Ws m/sec 99 9 d mm 99 U* m/sec A m 9 9 B m 9 Rh m 9 ⱱ m/sec Ws m/sec 99 Abed-Al- Al- Rahman U* m/sec 9 These formulas have been tested -Sediment Transport s The formulas used to estimate the quantity sediment were -Hansen -White with the measured data to show which to be nearly credible considered as a predictive formula for river reach in this study A summary the sediment discharge variables by the investigators as shown in table

4 International Journal Scientific & Engineering Research Volume Issue July- ISSN 9- Table : A summary sediment parameters Author Hansen9 White9 Van Rijn The particle mobility factor Fgr is calculated by: F parameters used V ℎ 9 cited in[] developed an analytical concentration The transport equation can be expressed in a simplified form when only the mean velocity flow depth particle size are known was given as: * The meanings each symbol are presented in list symbol Modified 's -Hansen -Hansen's9 [] equation is based on the shear stress approach The equation can be written as: the saltation height particle velocity bed load relationship for sediment load transport in terms ν Modified 's 99 [] proposed modified 's unit stream power formula for a sedimentladen rivercomputing the sediment concentration from log log White White 9 [] [] used dimensional analysis based on flow power concept as explained by ʋ Bagnold in order to express sediment transport rate by several dimensionless parameters Their proposed log ʋ ʋ 9 log ʋ log + 9 ʋ formula was as follows [ ] U* c m This formula was derived using laboratory data with particle size larger than mm Froude number less than Abed-Al-Rahman The dimensionless particle d is calculated by: d d / Abed-Al-Rahman [] evaluated the amount total sediment load entering the Al-Qadisiya reservoir The analysis was made on six sediment transport formulas -Hansen White Maddock Graf-Acaroglu Karim-

5 International Journal Scientific & Engineering Research Volume Issue July- ISSN 9- Table : Predicted observed values sediment discharge in kg/sec Kennedy to check the applicability each transport formula C Sec No Ariﬃn [] derived her sediment transport equation based on regression She conducted tests on the robustness on the variables used in her equation Her proposed equation is: Sec No C city on Euphrates He had been found by a new Sec No proposed formula which had no significant difference with the observed values The coefficient determination his formula was found to be equalr9 ℎ ѵ Sec No [9] estimated the total amount Sediment Load at the upstream Al-Shamia Barrage which is located in the middle Iraq within the province Diwaniya on Euphrates river Derivation this formula required the selection sections along entire study reach reach in order to measure the hydraulic parameters different cross sections the the properties sediment [] estimated the total sediment load entering Al-Abbasya Barrage in Al Najaf Table is presented the predicted observed values sediment discharge Sec No

6 International Journal Scientific & Engineering Research Volume Issue July- ISSN Sec No Sec No In which is a Mean Stard Error; observed sediment rate; sediment load an is a predicted is the number the predicted value In this method a lower statistical criterion close to zero shows a higher accuracy in the model performance Table explains these results This method gives a general evaluation for whole results by each used formula Table : Comparison using Mean Stard Error % 9% % 9% Abed-Al-Rahman -Test the efficiency the proposed formulas To determine the efficiency the selected formulas the predicted sediment discharge by % % % 9% using these formulas were compared with observed sediment discharge in the reach B- Discrepancy Ratio study there are two methods comparisons which are statistical methods graphical It is defined as the ratio between computed comparison measured sediment loads It was used as an error measure that is calculated as[] Comparison Using Statistical Relations Three methods are used in this research to evaluate Discrepancy Ratio 9 the performance each formula through comparing When the discrepancy ratio is equal to one with measured values R[] for the values a selected formula A- Mean Stard Error that indicate the predicted value is identical to the measured value for reach study The A mean stard error was used in order to discrepancy ratio is scheduled with the select the best formula since due to the high ranges difference The results are presented in table for twenty one set data between predicted measured sediment rates at various intervals []

7 International Journal Scientific & Engineering Research Volume Issue July- ISSN 9- Table : Comparison using Root Mean Table : Comparison between the computed the measured values Squared Error Discrepancy ratio Percentage data in the No range data % % % % % % % % % % 9% 9% 9% % 9 Abd-Al- Rahman Graphical Comparison A graphical comparison is conducted on the formulas by calculating the deviation predicted sediment discharges from measured or by means C- Root Mean Squared Error The root mean square errorrmse calculation is a well known frequently used method error analysis It accurately depicts the magnitude deviations estimated measured or calculated value from the actual value sought[] The RMSE has the same units as the measured calculated data Smaller values indicate better agreement between calculated values[9] the measured the discrepancy ratio [] 9 Kg/sec % 9 Sediment Discharge Kg/sec Fig : Comparison between measured computed sediment load by using Hansen In which: observed sediment rate predicted sediment load is is the number predicted values The results are shown in table

8 International Journal Scientific & Engineering Research Volume Issue July- ISSN 9- Kg/sec Kg/sec Sediment DischargeKg/sec Sediment DischargeKg/sec Fig : Comparison between measured Fig : Comparison between measured computed sediment load by using -White computed sediment load by using Kg/sec Kg/sec Sediment DischargeKg/sec Fig : Comparison between measured computed sediment load by using 9 9 Sediment DischargeKg/sec Fig : Comparison between measured computed sediment load by using Abed-Al Rahman

9 9 Kg/sec Kg/sec International Journal Scientific & Engineering Research Volume Issue July- ISSN 9-9 Sediment DischargeKg/sec Sediment DischargeKg/sec Fig 9: Comparison between measured computed sediment load by using sadiq Fig : Comparison between measured computed sediment load by using Kg/sec - Conclusions According to the results which are obtained by this study for twenty one cross sections on Euphrates river up-stream Al- Hafar regulator in Al- Nasiriyah city the following points are concluded: - The sediment particle size analysis showed that the bed material river is composed S Silt Clay The large portion bed material is sy material with the median grain size 9 mm Sediment DischargeKg/sec - Eight sediment transport formulas used in this research to estimate the total sediment load were -Hansen -White Fig : Comparison between measured computed sediment load by using Abed-Al- Rahman the best performance was produced by formula followed by -Hansen formula In formula gave mean stard error equal to %discrepancy ratio equal to 9% within the ranges - RMSE equal to While -Hansen formula gave mean stard error equal to %

10 International Journal Scientific & Engineering Research Volume Issue July- ISSN 9- discrepancy ratio equal to % within the same [] H Mohammed Estimation range RMSE equal to Sediment Quantity up stream Al-Abbasiya - The average predicted annual total sediment barrage in Euphrates River MSc Thesis transport is about Ton in the study Department Civil Engineering University Kufa [9] - References [] Omran Hassan A" Sedimentj Transport in Construction University Mohammed" Evaluation Barrage"" MSc Thesis Department Civil AL-Adhaim River Basin" Thesis Department Building N Sediment Transport up Stream Al-Shamia Engineering University Kufa technology the requirements for the degree [] C T "Erosion Sedimentation doctor Manual" US Department the Interior F [ Johnson L L" A Comparison Methods for for Estimating RMS Error: A "Brute Force" Computing Sediment Load in Al-Meshkhab Approach Versus a Mathematically-Elegant Regulator Channel" Jordan Journal Civil Approach as Applied to the Calculation a Engineering vol No Specific Retrieval Error for a Limb-Scanning [] Khassaf S "Development I Addab Empirical H Microwave [] Monowar M H Lutfor M R " Sediment transport functions their Air evaluation using data from large alluvial rivers Bangladesh University [] Hassanzadeh H Faiznia S Shafai B M Motamed A"Estimate Sediment Transport Rate at Karkheh River in Iran Using Education Training Comm - List symbols Engineering Technology IAHS Publ no 9 99 Sc AFIT/GAP/ENP/9D- December 99 Bangladesh" Department Water Resources Engineering Radiometer-Spectrometer"M Thesisthe Faculty the School Engineering Total sediment discharge BW Width the river V Mean flow velocity Selected Transport s" World Applied Gravitational acceleration Sciences Journal : - ISSN Shear stress along the bed Specific gravity 9 IDOSI Publications [] Sa'adon M S "Artificial Neural Network Sediment Transport Model for Sungai Bernam" D d Median grain size MSc Thesis Faculty Civil Engineering Weight concentration bed material University Technology Mara Transition exponent depending on sediment [] Mukheif RA "Hydraulic Sediment Transport in Number Alluvial Channels" size MSc Thesis Department Of civil Engineering University Of Babylon Department Civil m Exponent in the sediment transport function Engineering [] Abd-Al-Rahman KZeidan Evaluation Concentration coefficient in the sediment transport function Sediment Transport Entering the reservoir Al Critical particle mobility factor Qadisiya Dam MSc Thesis Department Civil Engineering University Al Anbar Bed shear velocity m/s F Particle mobility parameter

11 International Journal Scientific & Engineering Research Volume Issue July- ISSN 9- d Dimensionless particle diameter ⱱ kinematic viscosity h Average depth flow V Critical velocity S bottom slope ws sediment fall velocity b s Volumetric bed load transport Volumetric suspended load transport R R hydraulic radius S density fluid Density sediment

International Journal of Scientific & Engineering Research, Volume 6, Issue 3, March ISSN

International Journal of Scientific & Engineering Research, Volume 6, Issue 3, March-2015 1338 Modeling of Sediment Transport Upstream of Al- Shamia Barrage Prof. Dr. Saleh I. Khassaf, Mohammed jaber Abbas