钢渣水泥稳定混合料的耐久性研究：抗冻融、抗渗与硫酸盐侵蚀性能

Research on the Durability of Steel Slag Cement Stabilized Mixture: Freeze-Thaw Resistance, Impermeability and Sulfate Erosion Resistance

摘要: 在道路工程可持续发展需求日益迫切的背景下，钢渣作为工业固废在水泥稳定混合料中的应用已得到力学性能验证，但其长期耐久性数据仍存在缺口。为探究钢渣混合料在复杂环境下的服役性能，以4%水泥含量为基准，设计钢渣掺量25%、50%、75%的三组混合料，通过快速冻融循环(−20℃~20℃，50次)、渗水系数测试及5% Na₂SO₄溶液侵蚀试验，系统分析其抗冻融、抗渗及抗硫酸盐侵蚀性能。结果表明：50%钢渣掺量时冻融后抗压强度损失率最低(12.3%)，渗水系数较纯砾石混合料降低28.5%；硫酸盐侵蚀下钢渣混合料膨胀率随龄期呈先升后降趋势，28天峰值达0.32%。本文为钢渣混合料在寒区、盐渍土等特殊环境道路基层的应用提供了关键数据支撑。

Abstract: Against the backdrop of the increasingly urgent demand for sustainable development in road engineering, the application of steel slag as industrial solid waste in cement-stabilized mixtures has been verified for mechanical properties, but there is still a gap in its long-term durability data. To explore the service performance of steel slag mixtures in complex environments, three groups of mixtures with steel slag dosages of 25%, 50%, and 75% were designed based on a 4% cement content. Through rapid freeze-thaw cycles (−20˚C to 20˚C, 50 times), water permeability coefficient tests, and erosion tests with 5% Na₂SO₄ solution, systematically analyze its freeze-thaw resistance, impermeability and resistance to sulfate erosion. The results show that when the steel slag content is 50%, the loss rate of compressive strength after freeze-thaw is the lowest (12.3%), and the water permeability coefficient is 28.5% lower than that of the pure gravel mixture. Under sulfate erosion, the expansion rate of steel slag mixture showed a trend of first increasing and then decreasing with age, reaching a peak of 0.32% at 28 days. This article provides key data support for the application of steel slag mixtures in road base layers in special environments such as cold regions and saline soil.