摘要
为推动道路工程绿色低碳转型,提升问题性黏土的工程适用性,开展了再生混凝土骨料与高炉矿渣协同改性高液限黏土的试验研究。基于不同再生混凝土骨料与高炉矿渣掺量组合,分别进行击实试验、无侧限抗压强度(UCS)试验、加州承载比(CBR)试验、pH测定、回弹模量(E_(50))分析。结果表明,再生混凝土骨料掺入可显著降低高液限黏土的液限与塑性指数,提升了最大干密度,改善了击实性能。无侧限抗压强度(UCS)试验结果显示,当再生混凝土骨料(RCA)掺量为20%、高炉矿渣(GBS)为9%时,改性黏土在28 d龄期下的强度为原始黏土的14倍以上,满足道路基层力学性能要求。加州承载比(CBR)试验表明,复合掺加可将加州承载比值(CBR值)从3%提高至30%,同时将膨胀率由7.4%降低至1.4%。此外,回弹模量与无侧限抗压强度之间呈现显著线性相关性(R^(2)=0.98),验证了改性土体变形模量提升规律。结合pH测试与微观分析结果,进一步揭示了该复合材料在化学稳定与结构增强中的协同机制。研究成果为再生材料在可持续道路工程中的工程化推广提供了理论依据与实践支撑。
To promote the green and low-carbon transformation of road engineering and enhance the engineering applicability of problematic clays,conducts an experimental investigation on the synergistic modification of high liquid limit clay using recycled concrete aggregate(RCA)and granulated blast furnace slag(GBS).Based on different combinations of recycled concrete aggregates and blast furnace slag content,compaction tests,unconfined compressive strength(UCS)tests,California bearing ratio(CBR)tests,pH determination,and rebound modulus(E_(50))analysis were conducted separately.The results indicate that the incorporation of RCA significantly reduces the liquid limit and plasticity index of high liquid limit clay,increases the maximum dry density,and improves compaction characteristics.UCS tests revealed that when the RCA content is 20%and GBS content is 9%,the modified clay achieves a 28-day strength more than 14 times that of the untreated clay,meeting the mechanical requirements for road base layers.CBR results demonstrate that the composite stabilization approach increases the CBR value from 3%to 30%,while reducing the swelling potential from 7.4%to 1.4%.In addition,there is a significant linear correlation between rebound modulus and unconfined compressive strength(R^(2)=0.98),validating the enhancement trend of the deformation modulus in the stabilized soil.Combined with pH measurements and microstructural analysis,the study further reveals the synergistic mechanism of chemical stabilization and structural reinforcement in the RCA-GBS composite system.These findings provide both theoretical foundation and practical support for the engineering application and sustainable promotion of recycled materials in road construction.
作者
王孟林
曹威
刘正楠
张锐
WANG Menglin;CAO Wei;LIU Zhengnan;ZHANG Rui(HNCIG Communications Construction Co.,Ltd.,Changsha,Hunan 410004,China;Hunan Communications Research Institute Co.,Ltd.,Changsha,Hunan 410114,China;School of Transportation,Changsha University of Science&Technology,Changsha,Hunan 410114,China)
出处
《公路工程》
2025年第3期231-240,共10页
Highway Engineering
基金
国家自然科学基金项目(51478054)。
关键词
再生混凝土骨料(RCA)
高炉矿渣(GBS)
高液限黏土
力学性能
道路工程
Recycled Concrete Aggregate(RCA)
Granulated Blast furnace Slag(GBS)
high liquid limit clay
mechanical property
road engineering
