The foundry industry needs effective, alternative methods to reuse the recycled waste foundry sand (WFS) other than landfills, under the new lenient legislations in Finland. In this study, the viability of stabilized WFS and crushed rock mixtures were evaluated for applications in structural layers in pavements through a series of laboratory tests and analysis. Mechanical properties including flexural and compression strength of the binders, unconfined compressive strength and resilient modulus of the mixtures were determined by standard laboratory testing methods, to provide baselines for the viability evaluations. To ensure proper durability of the mixtures as pavement construction materials, the long-term performance was investigated in terms of frost heave and resistance to freezing-thawing cycles. In general, stabilized WFS and crushed rock mixtures showed great potentials in strength and durability for pavement structural layers. Cost and emission assessment also showed that the use of foundry sand in a filter layer is beneficial in reducing cost and CO₂ emission by up to 50% and 46% compared with reference structures. This paper provides insight into the possibility and way of characterizing and improving recycled and secondary material properties for reuse in civil engineering projects. Recommendations are provided on how to further investigate and improve the properties of the stabilized WFS mixtures, and recycled materials in similar for reuse in pavement constructions.

根据芬兰新的宽松法规，铸造行业需要有效的替代方法来重新利用除垃圾填埋场之外的回收废铸造砂（WFS）。在这项研究中，通过一系列的实验室测试和分析，评估了稳定的WFS和碎石混合物在路面结构层中的可行性。力学性能包括粘合剂的弯曲和压缩强度，混合物的无侧限抗压强度和弹性模量，是通过标准的实验室测试方法确定的，从而为可行性评估提供了基准。为了确保混合物作为路面建筑材料的适当耐久性，从霜冻胀大和抗冻融性的角度研究了其长期性能。一般来说，稳定的WFS和碎石混合物在路面结构层的强度和耐久性方面显示出巨大潜力。成本和排放评估还表明，在过滤层中使用铸造砂有利于降低成本和降低二氧化碳排放与参考结构相比，其₂发射分别高达50％和46％。本文提供了对表征和改善可重复利用和二次材料特性以在土木工程项目中重复使用的可能性和方式的见解。提供了有关如何进一步研究和改善稳定的WFS混合物以及类似材料的再生材料以在路面结构中重复使用的建议。