Function evaluation of reformed waterproof layer over frozen ground in mining area based on W-OH
To address the challenges associated with forming frozen ground in permafrost mining areas,five con-centrations of W-OH(0%,1.5%,2.5%,3.5%,and 4.5%)were applied to the bottom of disturbed soil bodies to re-form the waterproof layer at Muli mining area,Qinghai Provinve,China.Compressive tests,infiltration tests,and simulated rainfall tests were conducted to evaluate the reformed waterproof layer from three perspectives:physi-cal performance,infiltration and sediment yield,and cost-effectiveness.Eight key factors influencing the re-formed waterproof layer were identified using the analytic hierarchy process and expert scoring method,leading to the development of a functional evaluation system.The optimal scheme for the reformed waterproof layer was determined based on a comprehensive scoring approach.The results indicate:(1)W-OH enhanced the strength of coal gangue solidification,with the most significant improvement observed at 4.5%W-OH concen-tration.(2)Higher W-OH concentrations decreased the infiltration rate of the reconstructed aquiclude layer,ex-tended the steady infiltration duration,and reduced cumulative infiltration.(3)Under rainfall conditions,increas-ing the W-OH concentration lowered the stable infiltration rate of coal gangue solidification,increased the av-erage runoff rate,and elevated sediment yield.Besides,the average runoff rate and the average sediment yield are positively correlated with the concentration of W-OH and the slope gradient.(4)While the 4.5%W-OH concentration scheme achieved the highest comprehensive functional score,it posed practical challenges,such as clogging nozzles during application.Therefore,the 3.5%W-OH concentration scheme,which had the second-highest score,is recommended for practical implementation.These findings provide a theoretical basis for apply-ing W-OH to reform waterproof layers over frozen ground in alpine mining areas.
coal refusesW-OHcompressive testinfiltration testsimulated rainfall testanalytic hierarchy process
万方数据
维普
