电石渣改良路基过湿土的微观机制研究

发布时间：2018-01-21 13:02

本文关键词： 土力学电石渣路基过湿土 pH值压汞热重分析　出处：《岩石力学与工程学报》2014年06期 　论文类型：期刊论文

【摘要】：为揭示电石渣改良路基过湿土的强度增长机制,通过无侧限抗压强度、酸碱度、压汞和热重分析试验,从微观角度出发,探讨改良土强度与pH值、孔径分布、火山灰反应产物含量的内在联系,并与石灰改良土进行比较。结果表明,电石渣改良路基过湿土早期强度与生石灰改良土接近,而后期强度为生石灰改良土的1.05~1.16倍;电石渣细粒含量约为生石灰的1.72倍,比表面积大5倍,可保障电石渣与土颗粒接触更充分;电石渣活性Al,Si成分含量约为生石灰的1.71倍,且电石渣改良土pH值可维持在12.4~12.6(而生石灰改良土pH值低于12.4),为火山灰反应提供较好的碱性环境,水化反应更持久;28和120 d龄期时,电石渣改良土的火山灰反应产物含量约为生石灰改良土的1.06和1.10倍,且微孔隙(0.007μm)和小孔隙(0.007~0.900μm)的体积百分比之和分别约为生石灰改良土的1.05和1.23倍,结构更致密。
[Abstract]:In order to reveal the mechanism of strength growth of overwetted soil improved by carbide slag, the strength and pH value and pore size distribution of improved soil were discussed by unconfined compressive strength, pH, mercury injection and thermogravimetric analysis tests. The results show that the early strength of calcium carbide slag modified overwet soil is close to that of quicklime modified soil. In the later stage, the strength was 1.05 ~ 1.16 times as much as that of lime modified soil. The content of fine particles of carbide slag is about 1.72 times of that of quicklime, and the specific surface area is 5 times larger, which can guarantee the contact between calcium carbide slag and soil particles more fully. The content of active Al-Si in calcium carbide slag is about 1.71 times of that of quicklime, and the pH value of calcium carbide slag modified soil can be maintained at 12.4 ~ 12.6 (while the pH value of quicklime modified soil is lower than 12.4). It provides a better alkaline environment for the volcanic ash reaction, and the hydration reaction is more durable. At the age of 28 and 120 days, the content of pozzolanic reaction products of calcium carbide slag modified soil was 1.06 and 1.10 times as much as that of quicklime modified soil. In addition, the volume percentages of micropore (0.007 渭 m) and micropore (0.007 ~ 0.900 渭 m) are about 1.05 and 1.23 times as much as those of quicklime modified soil, respectively, and the structure is denser.
【作者单位】：东南大学岩土工程研究所;
【基金】：国家自然科学基金资助项目(51278100,41330641) 江苏省自然科学基金资助项目(BK2012022)
【分类号】：U412.22;U416.1
【正文快照】： 1引言过湿土天然含水率高,黏粒含量较多,塑性指数较大,强度及渗透性低,作为路基填料时,存在含水率降低慢且不均匀、压实困难、水稳性差等问题,须经改良才可碾压使用。电石渣是电石(CaC2)水解生成的工业废渣,其含水量高、碱性强且流量大,是污水管网的重点污染源。并且,堆放电石

【相似文献】