Damage Of Subgrade Slope Erosion Of Highway Pavement Drainage

In recent years,the mileage of low grade highway in China has been greatly increased,which brings convenience to people's life and economic development,but also brings problems on highway maintenance and protection.The erosion of roadbed slope by pavement confluence is a serious problem,especially in the rainy mountain area.The erosion of the slope is a comprehensive reflection of the joint action of the hydraulic and the soil conditions.At present,most researches on erosion and erosion on the slope are based on loose or water disintegration soil particles,which do not take into account the influence of soil erosion and brush erosion.From the internal and external factors affecting erosion erosion,this paper fully considers the effect of hydraulic conditions and soil conditions on the erosion of brush erosion.Through theoretical analysis and physical model test,the erosion of subgrade slope is studied.The main work and research results of this paper are as follows:(1)Based on the hydraulic condition,through the stress analysis of the soil particles on the slope during scouring and erosion,the main punching shear force of erosion is the impact force and additional shear stress generated by the flow.The influence factors of the initial hydraulic conditions of the brush are analyzed in view of the characteristics of the pavement confluence.(2)It is found that the soil condition has a great influence on the erosion erosion through the simulation of the erosion of the slope surface through the physical model test.The compaction degree of slope soil decreases and its cohesive force decreases.Under the same hydraulic conditions,erosion is more serious.The viscosity of sandy soil is smaller than that of clay.Under the same condition,the ability to resist erosion is weak.In the erosion process of the slope soil,the small particles are the main particles.With the decrease of the degree of compaction of the slope,the content of the large particle s ize increases gradually.(3)Combined with soil erosion and erosion process,the mechanism of erosion and erosion is analyzed,and erosion erosion model is established.The critical condition for erosive erosion is put forward: the effective force between soil particles and soil is not greater than that of water flow.Based on the erosion model and the critical erosion condition,the erosion erosion strength formula is derived,and the relationship between scour erosion coefficient and soil force parameters is obtained through regression analysis.(4)Aiming at the present situation and characteristics of low grade highway erosion and destruction,the canvas is introduced to the pavement to p rotect the roadbed from erosion.Through experiments and similar en gineering cases,it is shown that the canvas is effective in the slope protection.