Hamed Haghnazar; Ramin Amini; Mojtaba Saneie
Abstract
Evaluation of mining methods and the volume of the bed and flood plain sand and gravel mining show that many problems will be created due to geometry and naturally changing of rivers, increasing of the flood power and environmental and ecological dangers. Hence, applying correct management on river sand ...
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Evaluation of mining methods and the volume of the bed and flood plain sand and gravel mining show that many problems will be created due to geometry and naturally changing of rivers, increasing of the flood power and environmental and ecological dangers. Hence, applying correct management on river sand and gravel mining can create many positive effects. In this research, the effect of locating of the consequent river bed material mining pits on their sedimentation is investigated in order mining management via an experimental study. Results indicated that, there is no perceptible effect on the infilling and migration velocity of the upstream pit by increasing the distance between the pits up to 16 times the flow depth. Also, mining near the wall of the channel (20% width of the channel) leads to decrease infilling volume up to 25% and decreases migration velocity of the upper edge of the upstream pit up to 37%. By increasing of the distance between the pits, infilling of downstream pit is decreased, but it depends on the distance between the downstream pit and the wall. When the distance between the pits doubles, migration velocity of the downstream pit decreases up to 70%. If the mining is located at the center of the channel and the pits are in close proximity, it creates more suitable condition due to the infilling and migration for upstream and downstream pits.
Mojtaba Saneie; Ali Forudi
Abstract
Weirs are one of the common structures for discharge and flow measurement. Therefore, these types of hydraulic structures depending on the purpose of usage, have different shapes. Weirs have been widely used for the purpose of flow measurement and flow control in open channels. Generally they are used ...
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Weirs are one of the common structures for discharge and flow measurement. Therefore, these types of hydraulic structures depending on the purpose of usage, have different shapes. Weirs have been widely used for the purpose of flow measurement and flow control in open channels. Generally they are used as normal weirs. For the purpose of flow diversion, they can also be used as side weirs or skew weirs. Various weirs of modified plan form have been suggested in the past to enhance their discharging capacity with minimum head over the weirs and to restrict the afflux. The aim of this study is to apply different methods to investigate the discharging capacity of a sharp-crested curved plan-form weirs under free flow conditions using original experimental dataset through the Artificial Neural Networks (ANNs) and Genetic Expression Programming (GEP) techniques. Subsequently, for training and testing of the proposed equation, experimental data of Kumar et al. have been used. A preliminary investigation on various GEP operators is also carried out for selecting the proper operators. The obtained results indicate that applied machine learning techniques have reliable performance in predicting discharging capacity of a sharp-crested curved plan-form weirs. Comparison of results obtained from this equation with the experimental data reveals high accuracy of the new equation of genetic programming and result of the ANNs. Determination coefficient of the proposed equation for discharge coefficient have been calculated as 0.956 and 0.924 for the model with best functions (F2 and F4), also this parameter calculated for ANNs as 0.962 for testing phase.
Ehsan Hajibabaei; Seyed Abbas Hosseini; Mojtaba Saneie
Abstract
Bedload movement plays an essential role in the process of bedload transport and morphological characteristics of rivers. Slope, flow rate and particle size are important parameters in the amount of bedload transport in the erodible beds. Many studies have been investigated the effects of these parameters ...
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Bedload movement plays an essential role in the process of bedload transport and morphological characteristics of rivers. Slope, flow rate and particle size are important parameters in the amount of bedload transport in the erodible beds. Many studies have been investigated the effects of these parameters on the non-erodible beds. In this research, performing a laboratory model in the erodible substrates, the effects of slope, flow rates, particle size and suspended particle concentration on the amount of bedload transport was investigated. The experiments were carried out in the discharge rate of 0.90 to 4.75 ls-1 with the concentrations of the suspended particles 0, 10gl-1 and the slopes of 2, 3 and 5 percent, on the uniform non cohesive particles with the grain diameter of 1.7 and 3.29 mm. The Froude numbers of these currents were obtained in the range of 0.93 to 1.51 and the non-dimensional bed load discharge was calculated in the range of 0.004-0.131. In the experimental results, the variation of the bedload transport capacity in relation to the discharge was shown in the different slopes and grain sizes. Furthermore, increasing the concentration of suspended particles to 10 gl-1, did not has a significant effect on the bed transport capacity. Applying dimensional analysis, the effective parameters on the non-dimensional bed load discharge (ϕ)were investigated. Moreover, to determine ϕ relation to the shear stress (ϴ), particle size (D*) and slope (S). In the scope of the experiment, an experimental relationship was proposed. Results indicated that for determining the non-dimensional bedload discharge in the steep slopes of erodible beds, considering the slope and dimensionless particle diameters as independent parameters had a better result than shear stress correction. Sensitivity analysis of effective parameters on the experimental relationship showed that the slope parameter had the most effect on the experimental relationship.
Mosayeb Heshmati; Yayah Parvizi; Mohamad Gheitury; Mojtaba Sanee; Samad Shadfar; Masud Goodarzi
Abstract
Abstract: land degradation, air pollution, food deficient, poverty as well as inequality are the main challenges worldwide. However, overcome these challenges are impossible without local inhabitants’ participation. The objective of this research was to evaluate the watershed management measures ...
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Abstract: land degradation, air pollution, food deficient, poverty as well as inequality are the main challenges worldwide. However, overcome these challenges are impossible without local inhabitants’ participation. The objective of this research was to evaluate the watershed management measures which measured through joint project by Forests, Rangelands and Watershed Organization (FRWM) and Middle East and North Africa Regions Program for Integrated Development (MENARID) in Razin watershed, Kermanshah, Iran during 2013-16. Local inhabitants were interviewed using questionnaire. The results explored that constructed measures comprise the pit- seeding, rain-fed orchard, stony dam, gabion and dyke. However, most of respondents did not agree with biological measures (pit- seeding, rain-fed orchard) due to limitation for their animal grazing, persuading land-use change and enhancing conflicts among them, while rare inhabitants were willing to rain-fed orchard due to their expects on rangeland ownership and loan opportunity. Approximately 85% of local people confirmed that they did not consult or collaborated during watershed management measures, although they had environmental friend ideas. They believed that mechanical measures are impossible solutions in terms of soil conservation, flood control, runoff harvesting and supplemental irrigation. Overall, local communities worried about climate change and its sever negative impacts on agricultural activities and livelihood, thus watershed management and governance should be taken urgent steps overcome or adapting hits of droughts due to their literacy and experience during recent years. It is concluded that local inhabitant's ideas and their participations should be considered as the necessary step to obtain the effective results and sustaining watershed management measures.
Hassan Goleij; Amirhamze Haghiabi; Mojtaba Saneie; Hojattallah Yonesi
Abstract
The percentage of flow diversion is the major cause of the formation of dimensions of separation zone such that with increasing the percentage of flow diversion, width and length of the separation zone decreased in the basic and sill experiments. However, by adding a 10ᵒskimming wall, the changing ...
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The percentage of flow diversion is the major cause of the formation of dimensions of separation zone such that with increasing the percentage of flow diversion, width and length of the separation zone decreased in the basic and sill experiments. However, by adding a 10ᵒskimming wall, the changing trend is different. At low percentage of flow diversion, dimensions of the eddy area decreased significantly and it increased with increasing the percentage of flow diversion. However, in general, the simultaneous usage of a 10 degree skimming wall and sill structures compared to basic and sill experiments, dimensions of separation zone in lateral intake decreased and the useful width of outlet flow at lateral intake increased and the separation zone and sediment accumulation at the entrance of lateral channel decreased. By examining the effect of the Froude number of flow (inlet flow) on dimensions of the eddy region, this parameter did not have any significant effect on it and its low impact could be connived. By investigating the width of separation line of flow in the surface and near the bed of channel bend, it was found that the flow diversion rate was the most important factor affecting this hydraulic parameter; since, at surface level of flow with increasing flow diversion ratio, this parameter increases and due to the creation of secondary flow and the change of surface flow pattern under the influence of the simultaneous application of a 10 degree skimming and dike structures, this parameter increases more. However, near the bed, in basic and sill experiments, this parameter increases with increasing flow diversion rate. However, the simultaneous application of 10-degree skimming and sill structures, the width of separation line of flow near the bed reduces by increasing the diverted flow
Yaser Mehri; Jaber Soltani; Mojtaba Saneie; Mohammad Rostami
Abstract
A side weir is a structure which is set in a side of main channel and used for discharge of additional flow, diverting excess water and water level control of channels and in irrigation and drainage systems. Due to difficulties presented in mountainous regions, lateral ‘piano key weirs’ could ...
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A side weir is a structure which is set in a side of main channel and used for discharge of additional flow, diverting excess water and water level control of channels and in irrigation and drainage systems. Due to difficulties presented in mountainous regions, lateral ‘piano key weirs’ could be used in arc-shaped channels. In addition, curved channels, which are commonly used in mountainous areas, are places that can be used to locate the side piano key weirs. In this research, experimental investigation was performed on side piano key weirs type B, type c and sharp crest side weir on flow in the 30 degree curved channel. Among the findings of the above survey, one could point out to the equality of the specific energy on the two edges of piano key lateral weirs, the changes of which equal 0.277% for type C piano key lateral weir and 1.98% for type B weir. Also, focusing on the empirical analyses, it becomes evident that the coefficient of discharge for piano key weir bears a higher quantity considering the more effective length corresponding to rectangular weir. Comparing the coefficient of discharge of the two weir types C and B, it becomes evident that type B weir has a better functioning in relation to type C.
