Plane 2D Numerical Simulation On The Local Scour At Piers Of Bridge

The depth and scope of local scour at pier of bridge are very critical parameters during the bridge design. The thesis firstly reviews briefly the flow configuration, the mechanism of scour and the effect factors, and then analyses the factors that are relevant with the depth of the equilibrium clear water in the formulae used usually at home and abroad. As the following, the thesis simulates the situation of flow field and scour at piers with plane 2D numerical module. And make a summarize and analysis guard of piers.The analysis concludes that there are many different formulae in literatures and design codes home and abroad at present. These experimental formulae were established primarily by the laboratory physical model built with different conditions and by theory analysis or linear regression and dimensional analysis methods. But during calculating the prototype structures, the results attained between different formulae are in large difference, and can't reflect the scope of scouring and deposition.The thesis utilizes the FESMWS module in the SMS software that is used to calculate stream and sand governing equations to establish two dimensional horizontal numerical simulation at piers and chooses a set of laboratory data to demonstrate the reliability and rationality of the simulation .The result indicates that the module can simulate the situation of flow and calculate the depth of clear water scour at the piers. Consequently, with the change of different factors affecting the depth of clear water scour, the thesis analyses the reasons of the equilibrium clear water depth nearby the piers. The result concludes that the modules can simulate the atmosphere of water flow and scour at piers well and have certain utilization, and the same time, instruct the design of the bridge in some facets.