钢渣微粉改良膨胀土室内试验研究

钢渣微粉是钢渣加工产生的副产品,一直未被有效利用。Ca2+含量占40%~60%,考虑是否可以用来有效改良膨胀土。分别对膨胀土、素土和不同钢渣微粉掺量的改良土进行液塑限试验、直剪试验、干湿循环试验,得到结论:钢渣微粉的掺入使得膨胀土液限下降,塑限上升,且掺量大于3%时液、塑限符合路基规范要求;钢渣微粉的掺入对于膨胀土强度具有很好的改良效果,且钢渣微粉的最优掺入比例为5%;钢渣微粉对干湿循环后膨胀率的下降以及强度的增长均有很好的改良效果。试验结果表明膨胀土通过钢渣微粉的改良后符合工程规范要求。

Micro-powder Improvements of Steel Slag Treated Expansive Soil

The steel slag fine powder is a by-product in the process of steelmaking and is still not utilized effectively . Ca2+ content in the steel slag fine powder is 40% ~60% ,but it is unknown if it's feasible to improve expansive soil ef-fectively .A series of laboratory tests based on plain soil and expansive soil improved by different amounts of steel slag fine powder were done .The tests include liquid plastic limit test ,direct shear test and wetting-drying test .Conclusions are as follows :the steel slag fine powder could decrease liquid limit and increase plastic limit .When the dosage exceeds 3% ,liquid plastic limit conform to subgrade criterion .The steel slag fine powder could also improve the strength of ex-pansive soil well and the optimal dosage is 5% .Steel slag fine powder can make expansion rate of the expansion soil after drying and watering cycle decrease and it also has good effects on improving the strength .Test results showed that steel slag fine powder has good effects on expansion soil improvements and the improved soil can satify the engineering criteri-on .