This study investigates the environmental and mechanical implications of incorporating silica fume into lime-activated thermo-mechanically treated waste concrete powder (TMWCP) to develop a sustainable clinker-free binder. The novel activation method involves thermo-mechanical treatment of WCP, followed by lime and calcium formate chemical activation. The results demonstrated that incorporating silica fume enhanced the pozzolanic reactivity, which led to the formation of C–S–H, pore refinement, and a dramatic increase in compressive strength. For instance, the incorporation of 20 % and 25 % silica fume exhibited compressive strength of 46 MPa and 43 MPa after 28 days of curing. The developed clinker-free binder with the addition of 20 % silica fume demonstrated a reduction in mineral resource consumption of 99.3 % and CO emissions of 13 % and 69.3 % compared to the sample without silica fume and ordinary Portland cement, respectively. This study offers a promising avenue for the widespread utilization of WCP as an environmentally friendly clinker-free binder.

中文翻译：

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废弃混凝土粉末活化可持续无熟料粘结剂的新方法


本研究调查了将硅粉掺入石灰活化热机械处理的废混凝土粉末 (TMWCP) 中的环境和机械影响，以开发一种可持续的无熟料粘合剂。这种新颖的活化方法包括对 WCP 进行热机械处理，然后进行石灰和甲酸钙化学活化。结果表明，掺入硅灰增强了火山灰反应性，从而形成 C-S-H、细化孔隙并显着提高抗压强度。例如，掺入 20% 和 25% 硅粉的固化 28 天后，其抗压强度分别为 46 MPa 和 43 MPa。与不含硅粉和普通波特兰水泥的样品相比，添加 20% 硅粉的无熟料粘结剂的矿产资源消耗量分别减少了 99.3%，二氧化碳排放量分别减少了 13% 和 69.3%。这项研究为 WCP 作为环保的无熟料粘合剂的广泛利用提供了一条有前途的途径。