下蜀土-膨润土混合土的膨胀性试验及机理研究

Experimental study and mechanisms of swelling properties of Xiashu-bentonite mixture

摘要: 下蜀土-膨润土混合土作为一种可选的衬垫材料,其膨胀性对城市垃圾卫生填埋场的安全性有重要意义。本文按不同的初始含水量(10%～20%)和膨润土掺量(5%～15%)共配制了9组混合土试样,并在不同的温度(30～50℃)条件下开展一系列无荷膨胀试验。试验结果表明:初始含水量是影响下蜀土-膨润土混合土膨胀的重要因素,初始含水量越高,试样膨胀性越小;混合土中膨润土掺量越高,膨胀性越大;温度对下蜀土-膨润土混合土的膨胀性也有重要影响,膨胀性随温度的升高增加,尤其对于膨润土掺量较高的试样,膨胀性的温度效应更明显。

Abstract: Xiasu-bentonite mixture is an alternative liner material,which plays an important role in the security of urban landfills.In this study,the swelling properties of 9 mixture samples with different initial water content(10% to 20%) and bentonite content(5% to 15%) were tested under different temperatures(30℃ to 50℃).The results indicate that the initial water content is a significant factor influencing the mixture’s natural properties.The swelling capacity decreases with increasing water content,a...