Lee Taegyu, Lee Jaehyun, Choi Hyeonggil
Technology Research & Development Institute, Daelim Industrial, Jongno-Gu, Seoul 03152, Korea.
School of Architecture, Kyungpook National University, Buk-Gu, Daegu 4566, Korea.
Materials (Basel). 2020 Mar 25;13(7):1505. doi: 10.3390/ma13071505.
In this study, experiments were performed on the applicability of mortars and concretes based on calcium sulfoaluminate (CSA) binders to facilitate the early strength development of ordinary Portland cement (OPC) under low-temperature conditions. An optimum mixture of CSA was evaluated to improve the early strength of OPC, and the effects of accelerators and retarders on this mixture were examined to demonstrate the applicability of the resulting concrete mixture. Furthermore, mixture applicability was validated by producing concrete at the Remicon Batcher plant and performing numerical simulations. As observed, the optimum CSA substitution rate for the realization of early strength was 17% of the total unit binder amount with CaO/SO and SO/AlO ratios of 1.9 and 1.25, respectively. Evidently, CSA in combination with NaSO as an accelerator promoted the early strength of concrete with OPC and secured its constructability using additional retarders to control the quick setting of concrete. Additionally, the activation of initial hydration at low temperatures yielded a compressive strength of 5 MPa/12 h or higher for the resulting concrete mixture.
在本研究中，对基于硫铝酸钙（CSA）粘结剂的砂浆和混凝土在低温条件下促进普通硅酸盐水泥（OPC）早期强度发展的适用性进行了试验。评估了CSA的最佳混合物以提高OPC的早期强度，并研究了促凝剂和缓凝剂对该混合物的影响，以证明所得混凝土混合物的适用性。此外，通过在Remicon搅拌站生产混凝土并进行数值模拟，验证了混合物的适用性。观察到，实现早期强度的最佳CSA替代率为单位总粘结剂用量的17%，CaO/SO和SO/Al2O3比率分别为1.9和1.25。显然，CSA与作为促凝剂的Na2SO4相结合，促进了含OPC混凝土的早期强度，并通过使用额外的缓凝剂来控制混凝土的快速凝结，确保了其可施工性。此外，低温下初始水化的激活使所得混凝土混合物的抗压强度达到5MPa/12h或更高。
