Study on flowability parameters and on-site application of in-situ filling ultra-high water slurry

MA Qiufeng; LIU Guolei; DONG Xiaoyong; LI Guoqing; HE Guozhi; CUI Yu; TIAN Jing

doi:10.11799/ce202411010

Abstract：In order to explore the two key parameters of hydraulic gradient and critical flow rate in the design of in-situ filling pipeline system,the existing hydraulic gradient and critical flow rate models were modified.Taking material A as the research object,indoor hydraulic tests were conducted to investigate the actual hydraulic gradient and critical flow rate of material A slurry under different inclinations and mass concentrations.The parameters were estimated,and the accuracy of the model was explored.The engineering inspection was conducted based on the in-situ filling of No.7105 abandoned roadway in Tianchen Coal Mine in southwestern area of Shandong Province.The research results indicate that:as the inclination angle increases,the hydraulic gradient gradually increases,and the inclination angle influence coefficient α has approximate linear relationship with the inclination angle of the pipeline.The near flow velocity is influenced by both the inclination angle and concentration,and the higher the concentration and inclination angle,the greater the critical flow velocity.α、β fitting formula,obtained from experimental data,is incorporated into the correction model.The error of the hydraulic gradient model results is within 10%,and the error of the critical flow velocity is within 5%.The on-site filling pipeline system designed based on two key parameters is unobstructed,and there is no siltation or severe wear of the pipeline,proving the feasibility of hydraulic gradient and critical flow rate in practical applications.