Effect Of Soil Cracks In Open-pit Coal Mine Drainage Field On Production Flow-infiltration

Opencast coal mine is of artificial accumulation in the process of coal mining has a platform-and slope deposit of giant loosely,in the rain after prone to subsidence,landslides and other disasters,and mine site edge fracture directly influences the development of the soil structure stability,site analysis of fracture morphology characteristics of soil,therefore,to understand the mechanism of moisture movement in the process of rainfall and the path to the site and the occurrence of geological hazards and protection is of great significance.Based on the analysis of the morphological characteristics of fractures of different width-as well as the influence of the characteristics of fractures on the runoff,infiltration and leakage of the drainage site under artificial rainfall conditions,the calculation equation was established,and the equivalent model runoff,infiltration and leakage were corrected through the solid model of fractures,and the modified equation was established.The results are as follows:The roughness of the solid fracture is between1.16 and 1.28,and the roughness of the fracture surface becomes larger and larger with the increase of the fracture width.The surface area of the solid fracture is 1.09?1.20 times of the equivalent model,and the projected area of the solid fracture is 0.91?0.95 times of the equivalent fracture.Fracture volume and fracture surface roughness have a power function relationship with fracture width and fracture surface area has an exponential function relationship with fracture width.Under the condition of three kinds of rainfall infiltration amount decreases with the elapse of time,with the increase of time,the amount of seepage in addition to the extreme rainfall events,infiltration rate decreases with the increase of crack width,the leakage quantity increases with the increase of crack width,the infiltration law after the leakage quantity>50%changes over the rule of leakage.After the rainfall was 90 mm/h,the leakage gradually occupied the main water volume of the whole infiltration,and was greatly affected by the crack width.The calculation model of runoff in the dump is R=-0.38211*B+0.31392*T-1.94077*E^-4*S+0.74977;The calculation model of runoff dump is:W=-0.04533*T+5.78353*E^-4*S+0.067*K-3.64515.The runoff amount under the two models in the same rainfall intensity,the cumulative infiltration amount,total amount increases with the increase in crack width and rainfall intensity showed a trend of increase,in the same condition,the amount of runoff entity crack is always less than the equivalent model,entity model cumulative leakage is always greater than the equivalent model of cracks.The corrected equations for the total runoff,cumulative infiltration and cumulative leakage of the cracks in the solid model are as follows:y₁=0.94x₁-0.35;y₂=1.42x₂-3.34;y₃=1.68x₃-0.55...