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Offshore oil and gas has become an important part of energy production on the national economic construction, national security strategy has important significance. Undersea oil and gas pipelines have transported continuously, throughput, easy management, etc., in marine engineering has been widely used. However, the submarine pipeline in which the marine environment is very harsh, in waves, tide and other water force in the pipe near the seabed are prone to scour erosion, resulting spanning submarine pipeline occurred, causing accidents, resulting in huge losses. Submarine pipeline under hydrodynamic scouring the seabed near the pipeline spanning damage caused by other issues, is an important pipeline project research in academic and engineering applications have a high significance. However, for complex pipeline on the seabed erosion mechanism of dynamic environments, existing research is not perfect, especially for silt seabed pipeline scour inadequate. The main purpose of this paper is to explore the physical model tests silt seabed pipeline erosion mechanism and effective method of protection. In the full investigation based on the results of previous studies, this paper based on large-scale flume experiments to simulate the pipeline tiled and half-buried two states, small waves, big wave, unidirectional flow, wave and current combined four kinds of hydrodynamic environment seabed erosion situation, and process piping erosion force change and surface soil pore pressure changes in real time. Firstly, a detailed description of each set of experiments pipeline near the seabed scouring process, compared to the pipeline erosion in different circumstances different. On this basis, the paper concludes: (1) Pipeline scour will not go on indefinitely, there exists a state of equilibrium; (2) scour process with regularity, each set of experiments, erosion sediment particles are started by Sport - Tunnel development - rapid erosion - to balance the development of this order; (3) Pipeline tile, diameter increase, wave period, wavelength increases which makes the balance of several factors that will increase the depth of scour, erosion intensified; (4) the combined effects of waves and currents, erosion quickly, much larger than the total amount of scouring both acting alone. However, due to the larger flow, waves can only accelerate erosion, does not affect the scour depth, so the balance is less than the depth of the big wave acting alone, nearly unidirectional flow role. In addition, this paper compares several equilibrium scour pipes commonly used formula is verified CHAO and HENNSSY model silt seabed for the most suitable. Secondly, the focus of the combined effects of wave and current force change and piping erosion process in surface soil pore pressure response. Finally, the current domestic and international common submarine pipeline scour protection technologies are introduced, and the undersea pipeline bionic protection technology - \
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