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One of the most dangerous issues in river engineering is erosion brought on by the flow around bridge piers, which causes failure. As a result, simulating scouring is a crucial technique for assessing the likelihood of scour-related bridge failure. The scour depth surrounding hydraulic structures (non-uniform piers) was investigated using various computational and laboratory models. This study examines the efficacy of the computational fluid dynamics (CFD) model in generating simulations of the scour depth along a bridge pier via the Flow3D software (version 10.1.1.3). k-ε model is built to more accurately consider the generation of turbulent kinetic energy and the anisotropic characteristics of the turbulence. The model’s calibration and verification are assessed using statistical metrics (Root Mean Square Error (RMSE), Mean Absolute Error (MAE), and coefficient of determination (R2)). Based on the statistical criteria, it may be concluded that the model’s results were promising because the discrepancy between the numerical and experimental models is negligible. The Froude number has been demonstrated to be a crucial factor that must be considered during the construction of piers, since reducing it will result in a decrease in longitudinal velocity and turbulent kinetic energy. Also, the Flow-3D program accurately reproduces the scour depth, flow, and velocity near the pier.

In recent years, CFRP is the most popular material in strengthening RC members (columns, beams, slabs…etc.) as well as the textile-reinforced mortar (TRM) was also used as an alternative method for strengthening RC columns. The present study includes fifteen circular RC columns: One control column, ten columns strengthened by one or two layers of CFRP using EBR or EBROG methods, two columns was strengthened by textile-reinforced epoxy on grooves and last two columns were strengthened by textile reinforced mortar without grooves. The parameters of this investigation are type of strengthening technique (EBR, EBROG and TRM), number of CFRP layers, and the grooves configuration. The results showed that the columns strengthened longitudinally with one or two layers of CFRP strips using EBR technique enhanced the load-carrying capacity by 2 and 7.13%, respectively, when compared with control column. However, the load carrying capacity of RC columns strengthened by EBROG increased by the range of 11.65% to 71.4%. in comparison with control column. Finally, TRM strengthening method enhanced the load carrying capacity by about 21% to 58.5%. Also, the results showed that the EBROG and TRM approaches were improved the stiffness and ductility of the columns in comparison with EBR method.

This paper employed a hydraulic model to investigate the transient flow and its hydrodynamic effects in a failed water supply pumping pipeline system during a sudden and unplanned power outage. The model was developed and then properly calibrated to make the system more efficient in locating and determining the change in pressure and discharge throughout the length of the pipeline. The simulation of the transient process was utilized using the method of characteristics. The model was conducted on a practical problem in a hydraulic system of pipelines and pumping station of a water supply-pumping station, which is possessed by Nasiriyah Water Supply Project No.1 The Giant Nasiriyah Water Project (GNWP), Thi-Qar, Iraq, where the power outage is the most common and unsolved problem. The project transmits water for more than 77 km to supply more than 800 thousand inhabitants in the dry areas in southern Iraq with drinking water. The pressure variation and flowrate change at different points for the system with the different timings shutting down were analyzed. The study results showed that the sudden shutdown of the pump generates fluid transients with highpressure variations and flowrate in different locations and times. The characteristics of pumping under the transient conditions showed high fluctuations during the movement between the pump shut-off point and mass flow points, and the magnitudes of the fluctuations decreased with the fading of the impact of the water hammer. The results also indicated that the studied system is experiencing high-pressure pulsations in the discharge of the pumping system in addition to negative pressures, and consequently threatening problems of collapses and severe cavitations are expected along the pipeline in the system. This study may help to prevent the pipeline pumping system from hazards due to transient pressure fluctuations using the most principal recommendations for engineering solutions. [ABSTRACT FROM AUTHOR]

The dried Iraqi marshlands were re-flooded after the year 2003. Because of the water shortage feeds the marshes during the last years, the re-flooded marshes began to dry again. The Al-Sanaf marsh is part of the Al Hammar marsh located in the Thi Qar province. It is not separated hydraulically from the Al Hammar marsh. The study suggested separating the two marshes by replacing the culverts under security dyke with uncontrolled weir to keep the area of Al-Sanaf marsh submerged. If there is any added water, it will cross from the suggested structure to the Al Hammar marsh. A hydrodynamic and water quality routing models (RMA2 and RMA4) were prepared based on mass conservation low, mass balance model, and four scenarios were applied for the Al-Sanaf marsh based on the incoming discharges. The suggested model was calibrated with field data measured in the marsh. The four suggested scenarios are to keep the requirement of the Al-Sanaf marsh restoration. The maximum submerged area of the marsh is 100 km2 under any operation conditions while this area was reduced to 72 km2 under low flow conditions (minimum inflow from the feeders). The three scenarios operated considering values of inflow from Euphrates River with the required inflow from Al Khamissiya canal to keep the minimum level of salinity in the submerged area. While the fourth scenario operated with the minimum value of discharge from all feeders. [ABSTRACT FROM AUTHOR]