干旱寒冷地区水泥稳定钢渣碎石基层特性研究

Study on the characteristics of cement-stabilized steel slag and gravel base in dry and cold region

为提高水泥稳定钢渣碎石在干旱寒冷地区的适用性,采用体积设计方法将不同水泥剂量和不同比例的钢渣与碎石掺配,基于内蒙古地区全年气候条件,采用温湿度环境箱研究常温、低温及变温养护条件对水泥稳定钢渣碎石基层强度和收缩特性的影响。结果表明:当水泥剂量为5%且养护温度为-5℃时,65%钢渣掺量基层试件在1,3,7和28 d的抗压强度较普通碎石基层分别提高75.66%,66.7%,62.5%和35.7%,在15~-5℃变温养护下抗压强度分别提高87.5%,57.9%,25%和24.4%。65%钢渣掺量基层试件在-5℃和15~-5℃养护28 d时的间接抗拉强度较普通碎石基层分别提高30.7%和25.7%,而同钢渣掺量的6%水泥剂量试件分别提高18.7%,29.9%和25.9%。收缩方面,5%水泥剂量的65%钢渣掺量基层在5和0℃养护温度下的收缩应变较普通水稳碎石基层减小46.8%和29.9%,较45%钢渣掺量基层减小27.7%和14.3%。在合理选用配比的情况下,低温及变温环境中钢渣基层在力学和收缩性能方面较水稳碎石基层优异,以期对类似地区钢渣基层问题的分析和解决提供借鉴和指导。

In order to improve the applicability of cement-stabilized steel slag crushed stone in dry and cold regions,the volume design method is used to mix different cement dosages and different proportions of steel slag and crushed stone.Based on the annual climate conditions in Inner Mongolia,the temperature and humidity environment equipment is used to examine the effect of low and variable temperature curing on the strength and shrinkage characteristics of cement-stabilized steel slag and crushed stone base.The test results show that in terms of strength,when the cement dosage is 5% and the curing temperature is -5℃,the compressive strength of the base specimens with 65% steel slag content at 1,3,7 and 28 d are respectively higher than that of the ordinary crushed stone base.75.66%,66.7%,62.5%,and 35.7%,and the compressive strength increased by 87.5%,57.9%,25% and 24.4 % respectively under 15~-5℃ variable temperature curing.At the same time,the indirect tensile strength of the 65% steel slag base specimens cured at -5℃ and 15~-5℃ for 28 d is 30.7%and 25.7% higher than that of the ordinary crushed stone base,while the same steel slag content of dose of 6% cement specimens was increased by 18.7%,29.9% and 25.9%,respectively.In terms of shrinkage,the shrinkage strain of the base layer with 5% cement dosage and 65% steel slag content at 5℃ and 0℃ curing temperature is 46.8% and 29.9% lower than that of ordinary water-stable crushed stone base.And compared with 45% steel slag content,the base was reduced by 27.7% and 14.3%.In the case of reasonable selection of the ratio,the steel slag base in low temperature and variable temperature environment is better than the water-stable crushed stone base in terms of mechanical and shrinkage performance.The research results can provide a guidance for the analysis of the steel slag base in similar areas.