Study On The Characteristics And In Fluencing Factors Of Wall Scouring Erosion In Earthen Sites

The cultural,artistic,scientific and other values inherent in the carrier of earthen sites fully reflect their rich historical connotations.However,short-term heavy rainfall often occurs in the northwest region,which can form sufficient runoff in the walls of earthen ruins,continuously eroding the soil and causing erosion hazards to the walls.In the past,researchers mostly conducted research based on the rainfall damage of earthen ruins,but did not deeply discuss the erosion effect of wall erosion.Based on this,this article collects meteorological and soil properties data from 12 typical soil sites in arid,semi-arid,and semi humid regions of the northwest region,develops a scientific and reasonable experimental plan,and obtains the process and deterioration characteristics of wall erosion under different influencing factors through indoor wall erosion simulation experiments.Subsequently,relevant literature,experimental phenomena,and experimental data are combined to analyze their influencing factors.The main conclusions of this article are as follows:(1)The initial runoff generation time is inversely proportional to rainfall intensity,sand content,and dry density;The overall changes in runoff and sediment yield are:first rapidly increasing,then slowly increasing to a stable state.The flow rate and average flow rate increase with the increase of rainfall intensity,duration,and dry density,but decrease with the increase of sand content;The sediment yield and average sediment yield increase with the increase of rainfall intensity and duration,but show a trend of first decreasing and then increasing with the increase of sand content and dry density.(2)In the early and middle stages after the formation of runoff,the main erosion is clay and silt particles,while in the later stages,sand particles continue to increase until they stabilize;The higher the sand content,the higher the sand content during initial and later transportation;The erosion of sand particles is more pronounced under conditions of high intensity rainfall,low sand content,and low dry density;In other cases,erosion is mainly caused by clay and silt particles.(3)The degree of erosion is positively correlated with rainfall intensity and duration,but shows a trend of first decreasing and then increasing with the increase of sand content and dry density.The decrease in the elevation value of the wall morphology and the increase in the slope value mean that the degree of erosion is greater,and the bottom is more obvious.In severe cases,the bottom may collapse or fall off.(4)The initial roughness value is related to the sand content and dry density.After erosion occurs,the roughness value is positively correlated with the degree of erosion,and the numerical value changes from isotropic to anisotropic.Among them,the maximum value appears in the vertical direction and the minimum value appears in the horizontal direction.(5)The physical and mechanical degradation characteristics indicate that the surface hardness loss rate,surface comprehensive color difference value,and wave velocity loss rate are positively correlated with rainfall intensity,rainfall duration,and sand content,but negatively correlated with dry density.(6)The main influencing factors of erosion include rainfall intensity,rainfall duration,sand content,and dry density;From the degree of correlation,it can be seen that the primary and secondary order of influencing factors is rainfall intensity>rainfall duration>dry density>sand content.