膨胀土具有吸水膨胀、失水收缩的性质,给工程带来极大的危害。为研究水泥改性膨胀土防护边坡效果,选取膨胀土及不同水泥掺量的改性膨胀土进行胀缩特性试验研究。研究结果表明南阳中膨胀土水泥改性的最佳水泥掺量为6%。将其作为防护加固材料换填南水北调中线渠道边坡的表层,并利用测斜管和变形管等仪器设备对其防护效果进行现场监测。监测结果表明:水泥改性膨胀土回填覆盖坡面表层可以解决膨胀土渠坡的浅层失稳问题。
Expansive soils have brought great harm to engineering projects due to the properties of water swelling and dehydration shrinkage. In this article, expansion and contraction tests were carried out on expansive soils mixed with varing cement content. Results suggest that the optimum cement dosage was 6%. The modified expansive soil was then used as reinforcement material to replace the surface layer of cannel slope in the middle route of South-to-North Water Transfer Project. The protection effect was field monitored by inclinometer pipe and deformation tube. Results prove that cement-treated expansive soil as a backfill could solve the shallow instability problem of expansive soil slope.
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