One of the important issues in hydraulic engineering is inspection of local scour depth around bridge pier. Using piles is one of the ways for confronting local scour and erosion. In this study, the experiments were conducted in an 8m long, 0.5m deep and 0.25m wide flume. And the effectof using piles and number of them observed on the amount of scour in three different Frude numbers. The shape ...

rade control structures are used to control bed erosion in steep small rivers mostly in the mountains. Scour downstream of this structure can lead to failure. Over the past years, the effect of different variables on this phenomena have been studied, however the effect of upward seepage which is common due to head difference of the banks water table or water surface level between the upstream a...

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In offshore structures, most of failures are caused by the lack of sufficient piles strength. Scour phenomena affects the load transition and the pile strength. The necessity of the consideration of scouring phenomena amplifies when the scour depth becomes remarkable, which can endanger the jacket stability. In this paper, a new method is used to consider the pile scouring using nonlinear pusho...

Laboratory tests were carried out to assess the local scour by three-dimensional wall jets from a square crosssection nozzle. To this end, three different tailwater depths were used and the jet expansion ratio was held greater than ten. Velocity measurements were conducted using a one component laser Doppler anemometer. The jet exit Reynolds number was maintained to 1x10 and this value can be c...

Downfall flows from different outlet hydraulic structures such as culverts and jetsthrowingtothe erodible downstream bed cause scour hole and changes in the downstream bed topography. Therefore,by performing some physical modeling tests on culvert jet flow under different angles, changes in the downstream bed topography under the effect of different parameters such as flow rate, depth of the ta...

Scour downstream (DS) of hydraulic structures (HS) may endanger the safety of the structures if the necessary precuations are not considered during the design stage. Normally, different measures produce different effects on reducing the maximum scour depth DS of HS. One of the important HSs is the abruptly enlarged (or sudden expanding) stilling basins. In this paper, the effects of different a...