煤矿安全2026，Vol.57Issue(5)：28-35,8.DOI:10.13347/j.cnki.mkaq.20250763
大口径套管浮力塞微膨胀混凝土配比试验研究
Experimental study on mix proportion of micro-expansion concrete for buoyancy plugs in large-diameter casings
摘要
Abstract
Gas drainage wells are special channels for extracting coal mine gas to the surface,and their construction safety is critic-ally important.With the deepening of coal mining,the diameter and weight of casings in gas drainage wells have increased,making the traditional suspension method unable to meet the safety requirements of casing running.The buoyancy casing technique has be-come a key solution,yet it suffers from the potential hazard of relative sliding between the cement buoyancy plug and the casing wall.To address this issue,micro-expansion concrete was proposed for preparing buoyancy plugs to enhance the bonding strength between buoyancy plugs and the casing wall.Nine groups of mix proportions of micro-expansion concrete were designed,and the ef-fects of water-cement ratio,expansion agent content,water reducer content,and fly ash content on the bonding strength between the cement buoyancy plug and the casing wall were systematically investigated through orthogonal experiments.The maximum pressure,the slope from the initial position to the maximum pressure,the slope from the maximum pressure to 20 mm displacement,and the pressure at 40 mm displacement obtained from the pressure-displacement curves were selected as evaluation indexes to quantitat-ively characterize the bonding performance of micro-expansion cement buoyancy plug specimens.Based on range analysis,factor-in-dex trend charts,and influence weight tables,the optimal mix proportion of high-performance micro-expansion concrete with bal-anced bonding properties was determined.The results show that the optimal mass ratio is cement:water:sand:gravel:expansion agent:water reducer:fly ash=1.000∶0.250∶1.360∶3.030∶0.100∶0.008∶0.150.关键词
浮力塞/正交试验/大口径套管/微膨胀混凝土/最佳配比Key words
buoyancy plug/orthogonal experiment/large-diameter casing/micro-expansion concrete/optimal mix proportion分类
矿业与冶金引用本文复制引用
许蕾,杨洋,李华,程桦,王雪松,宋春芳..大口径套管浮力塞微膨胀混凝土配比试验研究[J].煤矿安全,2026,57(5):28-35,8.基金项目
安徽理工大学高层次引进人才科研启动基金资助项目(2023yjrc15) （2023yjrc15）
