High-volume slag (HVS) can reduce the CO2 emissions of concrete, but increase the carbonation depth of concrete. In particular, because of the effects of climate change, carbonation will accelerate. However, the uptake of CO2 as a result of carbonation can mitigate the harm of CO2 emissions. This study proposes an optimal mixture design method of low-CO2 HVS concrete considering climate change, carbonation, and CO2 uptake. Firstly, net CO2 emissions are calculated by subtracting the CO2 emitted by the material from the uptake of CO2 by carbonation. The strength and depth of carbonation are evaluated by a comprehensive model based on hydration. Secondly, a genetic algorithm (GA) is used to find the optimal mixture. The objective function of the GA is net CO2 emissions. The constraints of the GA include the strength, carbonation, workability, and range of concrete components. Thirdly, the results show that carbonation durability is a control factor of the mixture design of low-strength HVS concrete, while strength is a control factor of the mixture design of high-strength HVS concrete. After considering climate change, the threshold of strength control increases. With the increase of strength, the net CO2 emissions increase, while the CO2 uptake ratio decreases.

中文翻译：

---

考虑气候变化和CO2吸收的低CO2大体积矿渣混凝土优化配合比设计

高体积矿渣（HVS）可以减少混凝土的二氧化碳排放，但会增加混凝土的碳化深度。特别是由于气候变化的影响，碳化会加速。然而，由于碳酸化而吸收 CO2 可以减轻 CO2 排放的危害。本研究提出了一种考虑气候变化、碳化和 CO2 吸收的低 CO2 HVS 混凝土的最佳配合比设计方法。首先，通过从碳化吸收的 CO2 中减去材料排放的 CO2 来计算净 CO2 排放量。碳化的强度和深度通过基于水化的综合模型进行评估。其次，使用遗传算法（GA）来寻找最佳混合。GA 的目标函数是净二氧化碳排放量。GA 的约束条件包括强度、碳化、可加工性、和混凝土构件的范围。第三，结果表明碳化耐久性是低强HVS混凝土配合比设计的控制因素，而强度是高强HVS混凝土配合比设计的控制因素。考虑到气候变化后，强度控制的门槛提高了。随着强度的增加，净CO2排放量增加，而CO2吸收率降低。