The seepage through a permeable soil under hydraulic structure exerts uplift pressure and may carry soil particles there by leads to piping. This paper concerns to study the effect of ...using intermediate sheet pile under the apron of hydraulic structure besides the upstream and downstream piles rest on non-homogeneous soil layer. This configuration aim to show how it affect the uplift pressure, exit gradient and seepage discharge at toe of hydraulic structure by using computer program SEEP/W Package. From the software test carried out two cases, first case using two sheet pile one at the upstream and the other at the downstream, then compare its results with the second case when the sheet pile at upstream, downstream and intermediate pile introduced Also for each run the quantity of uplift pressure, exit gradient and discharge at toe of hydraulic structure were determined to develop an empirical equations. Also, the results have been verify with artificial neural network (ANN), this verification shown good agreement between them.
The seepage through a permeable soil under hydraulic structure exerts uplift pressure and may carry soil particles there by leads to piping. This paper concerns to study the effect of using ...intermediate sheet pile under the apron of hydraulic structure besides the upstream and downstream piles rest on non-homogeneous soil layer. This configuration aim to show how it affect the uplift pressure, exit gradient and seepage discharge at toe of hydraulic structure by using computer program SEEP/W Package.From the software test carried out two cases, first case using two sheet pile one at the upstream and the other at the downstream, then compare its results with the second case when the sheet pile at upstream, downstream and intermediate pile introduced Also for each run the quantity of uplift pressure, exit gradient and discharge at toe of hydraulic structure were determined to develop an empirical equations. Also, the results have been verify with artificial neural network (ANN), this verification shown good agreement between them.
A lightning strike is considered one of the most risky natural phenomena that can lead to human harmful and the surrounding soil layers. To tackle this issue, this article investigates the influence ...of direct lightning characteristics in terms of human body safety. Specifically, such investigation is carried out on the effect of resistivities of two-layer soils on human safety when lightning stroke hits the towers of the high voltage transmission lines (HVTLs). The merit of the proposed study is that the soil ionization phenomenon is taken into consideration. Further, the study focuses on the current passing through the human heart, when step and touch (contact) voltages are generated by grounding potential rise, caused by direct lightning strikes transmission tower and the produced potential rise that a person could be exposed. Also, studying the effects of peak current and time of lightning strokes are investigated. Additionally, the paper presents the effect of different reflection factors on human safety. For validation purposes, the ATP program is used in the simulation of the grounding system as well as the human body model. Numerous simulations were accomplished in order to examine the behavior of the current passing through with the human heart. Based on the simulation results, it was concluded that the soil characteristics have superior influences on the contact and step potentials and, accordingly, the survival threshold.
