Research On Anti-scouring Performance Test And State Prediction Of Slope Protection By Three-dimensional Ecological Protection Blanket

With the development of social economy,people pay more and more attention to environmental protection,and the protection of river slope is also gradually paid attention to.The protection of the river slope not only needs to ensure the long-term stability of the slope,with good anti-erosion performance,but also can create a good landscape environment for the people,improve the quality of life of the people.Therefore,the protection method of river slope has gradually changed from engineering protection to ecological protection in the early stage,and ecological slope protection technology has been rapidly developed.In recent years,the new flexible three-dimensional ecological protection blanket has been widely paid attention to in river slope protection engineering,and it is of great significance to study its anti-scouring performance.Due to the difficulty of field test operation and many uncontrollable factors,based on the scientific research method of model test,this paper designed a set of composite flume scour test device to carry out related research on the anti-scour performance of three-dimensional ecological protection blanket slope protection.The three-dimensional ecological protection blanket slope protection samples are cultivated by artificial planting,and their structure composition,density and operation process are carried out according to the actual engineering.The three-dimensional ecological protection blanket slope protection samples can be preserved until they meet the requirements before they can be used in the test.The designed scour test device can carry out the scour test with pressure flow and the scour test with no pressure flow respectively,which can realize the scour test with high flow velocity under pressure condition,and can simulate the flow of open channel under no pressure condition,which is more similar to the actual situation.According to the analysis of the measured data,the shear stress on the bed surface of the three-dimensional ecological protection blanket increases with the increase of the flow velocity,and there is a nonlinear relationship between the two.Under the condition of the same flow rate,the value of the shear stress on the bed surface decreases obviously in the early stage of the test and remains relatively stable in the later stage.With the increase of scouring duration,the scouring depth of 3D ecological protection blanket increases,and the growth rate is obvious and gradually slows down in the early scouring period.In addition,a comparative test was carried out between the three-dimensional ecological protection blanket and the ordinary vegetation protection.The results show that the three-dimensional ecological protection blanket has a significant effect in improving the anti-scouring performance of the slope protection,and has a broad application prospect.The BP neural network model was built according to the scour test conditions and analysis requirements,and several groups of test data were used as samples for training.The scour depth and bed surface shear stress of three-dimensional ecological protection blanket were predicted.By comparing with the measured results,the model has achieved a good prediction effect,which provides an effective method for slope protection state prediction of three-dimensional ecological protection blanket.