The large quantity of steel slag deposit has caused great environmental pressure. This study aims to recycle steel slag as binder in the production of green ultra-high strength concrete (UHSC) subjected to different curing regimes (i.e. standard and steam curing). The fresh behaviors, mechanical properties, microstructure and ecological value of the UHSC are explicitly assessed with the help of the Funk and Dinger particle packing model. The results show that the inclusion of steel slag powder (SSP) increases the workability (up to about 13%) and wet packing density of UHSC. The use of SSP results in a decrease of early compressive strength, because the SSP inhibits cement hydration at early stage. The steam curing can minimize this negative impact of SSP on the early compressive strength (>120 MPa). Besides, the increase of SSP dosage results in a reduction in the flexural strength for both early and later ages, but steam curing reduces the decline ratio. The high temperature curing not only promotes the hydration process of both cement and SSP, but also accelerates the pozzolanic reaction of silica fume, resulting in a lower porosity (4.78%) of UHSC with SSP. Finally, the ecological assessment shows that the recycling SSP as a replacement of cement in the UHSC system can reduce energy consumption and carbon emissions. Therefore, the results in this study indicate the feasibility of utilizing SSP in the fabrication of sustainable UHSC products with excellent performance.

大量的钢渣沉积造成了巨大的环境压力。本研究旨在回收钢渣作为粘结剂，用于生产经过不同养护制度（即标准养护和蒸汽养护）的绿色超高强度混凝土 (UHSC)。UHSC 的新鲜行为、机械性能、微观结构和生态价值在 Funk 和 Dinger 颗粒堆积模型的帮助下得到明确评估。结果表明，钢渣粉 (SSP) 的加入提高了 UHSC 的可加工性（高达约 13%）和湿堆积密度。SSP 的使用导致早期抗压强度降低，因为 SSP 在早期阶段抑制水泥水化。蒸汽养护可以最大限度地减少 SSP 对早期抗压强度 (>120 MPa) 的负面影响。除了，SSP用量的增加导致早期和晚期的抗折强度降低，但蒸汽养护降低了下降率。高温固化不仅促进了水泥和 SSP 的水化过程，而且加速了硅灰的火山灰反应，导致 UHSC 与 SSP 的孔隙率较低（4.78%）。最后，生态评估表明，在 UHSC 系统中，回收 SSP 作为水泥的替代品可以减少能源消耗和碳排放。因此，本研究的结果表明利用 SSP 制造具有优异性能的可持续 UHSC 产品的可行性。高温固化不仅促进了水泥和 SSP 的水化过程，而且加速了硅灰的火山灰反应，导致 UHSC 与 SSP 的孔隙率较低（4.78%）。最后，生态评估表明，在 UHSC 系统中，回收 SSP 作为水泥的替代品可以减少能源消耗和碳排放。因此，本研究的结果表明利用 SSP 制造具有优异性能的可持续 UHSC 产品的可行性。高温固化不仅促进了水泥和 SSP 的水化过程，而且加速了硅灰的火山灰反应，导致 UHSC 与 SSP 的孔隙率较低（4.78%）。最后，生态评估表明，在 UHSC 系统中，回收 SSP 作为水泥的替代品可以减少能源消耗和碳排放。因此，本研究的结果表明利用 SSP 制造具有优异性能的可持续 UHSC 产品的可行性。