Use of high-cost raw materials such as quartz sand can limit wider application of ultra-high performance concrete in concrete construction. In this experimental study, recycled sand was used to fabricate ultra-high performance concrete (UHPC) and ultra-high performance fiber-reinforced concrete (UHPFRC). Green UHPC with ordinary Portland cement and industrial by-products such as silica fume, fly ash, as well as recycled sand was first developed through two-step packing density tests to optimize the mix design. UHPFRC was then developed based on the UHPC mix designs and by using 1%, 2%, or 3% 13-mm straight steel fibers (SSF). The compressive strength, elastic modulus, and flexural tensile strength was 128 MPa, 46.9 GPa, and 11.9 MPa, respectively, after 28 days at water-to-binder ratio of 0.17 and with 2% SSFs. All high-performance concretes in this work utilized 100% commercially available recycled sand that was produced by wet processing method. Mechanical characteristics such as strength, elastic modulus, and density, absorption, and voids of the UHPC/UHPFRC were investigated. Development of autogenous shrinkage of UHPC/UHPFRC with recycled sand was monitored for 12 weeks, while mercury intrusion porosimetry test and scanning electron microscopy were performed for microstructural investigation. Finally, the environmental impacts and economical aspects of the green UHPC were evaluated by life cycle assessment (LCA) and cost analysis.

使用石英砂等高成本原材料会限制超高性能混凝土在混凝土建筑中的更广泛应用。在这项实验研究中，再生砂被用来制造超高性能混凝土（UHPC）和超高性能纤维增强混凝土（UHPFRC）。首先通过两步填充密度测试来优化配合比设计，以普通波特兰水泥和硅灰、粉煤灰等工业副产品以及再生砂为原料，开发出绿色UHPC。随后，基于 UHPC 混合设计并使用 1%、2% 或 3% 13 毫米直钢纤维 (SSF) 开发了 UHPFRC。在水胶比为 0.17、SSF 为 2% 的情况下，28 天后，压缩强度、弹性模量和弯曲拉伸强度分别为 128 MPa、46.9 GPa 和 11.9 MPa。本次工程中的所有高性能混凝土均采用 100% 市售再生砂，通过湿法加工方法生产。研究了 UHPC/UHPFRC 的强度、弹性模量、密度、吸收率和空隙等机械特性。对使用再生砂的 UHPC/UHPFRC 自收缩的发展进行了 12 周的监测，同时进行了压汞孔隙率测试和扫描电子显微镜以进行微观结构研究。最后，通过生命周期评估（LCA）和成本分析来评估绿色UHPC的环境影响和经济方面。