The precast industry, due to its specific early-age strength requirements for hollowcore (HC) slab products, has been reluctant to introduce alternative cementitious materials such as ground granulated blast-furnace slag (GGBS) due to the slower strength development of such materials. This paper reports on a study undertaken at a precast production facility to examine how to overcome the consequences of strength loss due to the replacement of up to 50% of CEM I (42·5R), as usually used in cold weather conditions, with GGBS, for environmental or durability reasons. The GGBS concrete slabs were activated using thermal, chemical and mechanical means to enhance their early-age strength gain. The results were compared at early ages in terms of the temperature profile during curing, cube compressive strengths, load-carrying capacities for transportability requirements, ultimate load and short-term creep. In addition, 28 d densities and strengths were compared for in situ cubes and cores extracted from HC slab samples. The experimental results showed a favourable potential for replacing CEM I (42·5R) cement with up to 50% GGBS in winter without compromising on factory productivity.

中文翻译：

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用于冬季条件的具有替代胶凝材料的空心板

预制行业由于其对空心 (HC) 板坯产品的特定早期强度要求，一直不愿引入替代胶结材料，例如磨碎的高炉矿渣 (GGBS)，因为此类材料的强度发展较慢。本文报告了在预制生产设施中进行的一项研究，该研究旨在研究如何克服在寒冷天气条件下通常使用的高达 50% 的 CEM I (42·5R) 替换为 GGBS 所造成的强度损失后果，出于环境或耐用性原因。使用热、化学和机械方法激活 GGBS 混凝土板，以增强其早期强度增益。在固化过程中的温度分布、立方体抗压强度、可运输性要求、极限载荷和短期蠕变的承载能力。此外，还比较了从 HC 板样品中提取的原位立方体和芯的 28 d 密度和强度。实验结果表明，在不影响工厂生产力的情况下，在冬季用高达 50% 的 GGBS 替代 CEM I (42·5R) 水泥具有良好的潜力。