The scour phenomenon around bridge piers causes great quantities of damages annually all over the world. Collars are considered as one of the substantial methods for reducing the depth and volume of scour around bridge piers. In this study, the experimental and numerical methods are used to investigate two different shapes of collars, i.e, rectangular and circular, in terms of reducing scour ar...

Field observations and model simulations are presented of the tidal flow over a scour hole at the mouth of the Dyfi Estuary, mid-Wales, U.K. This scour hole is maintained by locally high flow speeds resulting from convergence, and then divergence, of the flow over the hole. Fixed features of the local bathymetry may also have served to stabilise its location (over decades). Model simulations of...

scoure is the removal of particle sediment which results variation of flow pattern. local scour is considered as one of the reasons of instability and ultimately failure of bridges.therefore, proposing some controlling methods to reduce this phenomenon is essential. in the study, effects of two types of squar and circular collar on a single cylindrical model have been investigated. in the next ...

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 ...

Social and economic damages are the most important damages of the bridge failure. Stability problems of such structures against failure and the depth of the abutments are directly related to the amount of the adjusted scour. Economy, reliability and stability have been main concerns regarding designing abutment bridges enhanced preventing scouring. In this study a detailed comparison of the up-...

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...

The erosion caused by jets issued from hydraulic structures progressively develops a confined scour-hole on the riverbed. A realistic scour assessment must consider both the influence of the air entrained when the jet plunges into the pool and the flow patterns induced by bottom geometry. This experimental study systematically analyzes the combined influence of jet aeration and pool confinement...