Risk Division Of Mine Debris Flow Based On FLO-2D

The mine debris flow is an artificial debris flow induced by the unreasonable accumulation of slag in the mining of mineral resources in the mountainous areas under strong rainfall conditions.It has strong catastrophic concealment,large impact damage,and a wide range of disasters.It is a prominent geological environment problem during the development and operation of mineral resources.Huilaiyu is located in the heavy mining area of coal,a large amount of slag(348.03×104m3)is accumulated in the channel,and the slag accumulation body has not been tamped to provide a rich source of debris flow.In this paper,the Huilaiyu mine debris flow is used as the research object.Based on field surveys,on-site in-situ screening tests,mathematical calculations,and numerical simulations are used to obtain single-source discharges,the disaster area,the accumulation thickness and the rate of debris flow under different rainfall conditions.,and the zoning study of the risk of debris flow based on the simulation results:(1)On the basis of the collection of rainfall data and geological data,through field investigations,the geological conditions,hydrogeological conditions,and morphological characteristics of the basin have been ascertained;The area of the sinking area,formation area,circulation area and accumulation area of the debris flow was investigated;The basic engineering geological characteristics and distribution location and scope of slag spoil slag within the catchment area were identified.(2)The typical slag deposits were selected for on-site testing.The in-situ screening test and particle size distribution analysis were used to determine the slag as non-adhesive coarse-grained soil.The type of debris flow was a dilute mudslide.The start-up mode was mainly slag slump instability and conversion to debris flow.(3)Based on the analysis of the dynamic characteristics and movement characteristics of debris flow,the flood peak flow rate of debris flow under(5,10,20,50,100,200years)in the six reproduction cycles was calculated using the rain-flood method,and the occurrence of flood was assumed.The frequency is the same as the frequency of mudslides.When the flood water is completely converted into a debris flow,the soil is added simultaneously.This assumes that the duration of the debris flow is the same as that of the flood.The clear water flow curve is plotted,and the debris flows under six reproduction cycles are obtained.In the past,based on this,the debris flow movement parameters such as flow velocity and flow rate were calculated.(4)Comparing the simulation results with the results of the empirical formula method,the errors of the flow rates at the six reproduction cycles(5,10,20,50,100,and 200 years)were 6.46%,9.33%,10.46%,and 13.28%.16.22% and 19.17% respectively.The error of debris flow outflow was 12.11%,23.98%,27.65%,30.38%,30.38%,32.28%,and 36.06%.The result of the empirical formula calculation is larger than the simulation result,and the model has certain reliability,which provides reference for quantitative analysis and evaluation of mine debris flow.(5)FLO-2D software was used to simulate the circulation accumulation of Huilaiyu debris flows that returned to the under the non-recurring period.According to the simulation results of debris flow velocity and accumulation thickness,the strength of the debris flow was divided,based on the intensity of debris flow,combined with the debris flow.The recurrence cycle was used to conduct a zoning study on the risk of debris flow,and the results of hazardous partitioning under different reproduction cycles were analyzed and evaluated.