NUMERICAL INVESTIGATION OF FLOW PATTERN AND SCOUR CHARACTERISTICS AROUND ELECTRICAL TOWER FOUNDATIONS

The presence of some high voltage towers in flood stream is one of the most important problems that may lead to the collapse of these towers. The main reason for collapse is the soil erosion around the tower foundation during flood. The shape of the foundation is a vital factor in scouring process. This research is focused on studying different shapes of a tower foundation and its effect on the maximum scour depth. A sediment scour model has been investigated by using Flow 3D V 11.2 Program. The numerical simulation results of the maximum scour depth surrounding a single square pile model have been assured using prior experimental findings and showed good agreement. After that, different four shapes of footing and five values of the inclination angle for pyramid and cone footing have been investigated. The results of cuboid footing have been used as a reference to compare with different shapes. Seventy-two numerical runs have been carried out considering the wide range of Froude number ranging from 0.26 to 0.50 under clear water condition. It is found that, for pyramid and cone footing, the lager the inclination angle, the smaller the scour depth will be and vice versa. The cone footing is better than the other footing shapes. An empirical equation has been developed by using the nonlinear regression to predict the relative maximum scour depth around the footing