Barrage Regulators are considered one of the most important hydraulic structures that used to control the released discharge and upstream and downstream water levels. New barrages are constructed on the River Nile instead of the oldest ones, which are not able to resist the requirements of increasing head difference upon their gates. The present study was focused on investigating experimentally the effect of sill over stilling basin of Nagaa Hammadi regulator on the length of reverse flow behind sill, velocity at the end of stilling basin, energy dissipation, length of submerged hydraulic jump and scour formation downstream regulator apron. Experimental work was carried out on a re-circulating flume with 1.0 m wide, 26.0 m long and 1.2 m deep, with discharges range from 40 to 190 l/s. It is found that the sill over stilling basin has great effect on flow characteristic and local scour depth formed downstream regulator especially for sill with right and slopped faces at the upstream and downstream, respectively. The present study shows that, the reverse flow length downstream sill decreases as the submergence ratio and Froude number increase. In addition, using sill with right upstream and slopped face at downstream with L s /L=0.6, reduces the length of submerged hydraulic jump by 59% in average and thus leads to decrease stilling basin length. Local scour depth downstream hydraulic structures were reduced by 43%. Moreover, the energy dissipation was increased by 30% compared to the no sill case. Finally, Empirical equations are developed using multiple linear regressions analysis.
Maintenance and repair of bridges represent significant costs in provincial and municipal government budgets. Prediction of bridge conditions can help managers in annual cost estimating and budget allocation. To assess Bridge Condition Index (BCI), each bridge component must be inspected every two years, tested if it is required, and rated. Bridge condition can be affected over time by different attributes such as material, structure, location, and use. This paper presents a study conducted to model and predict BCI based on a historical dataset of 2803 bridges in Ontario from 2000 to 2014. The paper describes the work related to data collection, cleaning and transformation. In addition, a comparison of the cross-validation performance of alternative BCI prediction models is presented and discussed.
Barrage regulators are considered as one of the most important projects in the Egyptian irrigation practice, which is obvious by its controlling of the released discharge and both of upstream and downstream water levels. In the present time, the ministry of water resources and irrigation starts to construct new barrages on the River Nile instead of the oldest ones, which are not able to withstand the requirements of increasing head difference between the upstream and downstream water levels upon the gates. The present study was focused on investigating the effect of different shapes of stilling basins of regulator on the length of the submerged hydraulic jump, velocity profiles along the apron, and local scour downstream regulator floor. Extensive experimental program was conducted on a re-circulating flume with 1.0 m wide, 26.0 m long and 1.2 m deep, with discharges range from 40 to 190 l/s. The relative velocity near bed, and shear Reynolds number were studied to fix the best shape of stilling basin that could reduce both of length of submerged hydraulic jump and local scour downstream stilling basin. Statistical equation was developed to correlate the length of submerged jump with the other independent parameters. Finally, clear matching of results from the length of jump and velocity analysis was investigated.ª 2010 Faculty of Engineering, Alexandria University. Production and hosting by Elsevier B.V.All rights reserved.
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