Modifying the pore size distribution in Fe-rich inorganic polymer mortars: An effective shrinkage mitigation strategy
Modifying the pore size distribution in Fe-rich inorganic polymer mortars: An effective shrinkage mitigation strategy
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DOI：
10.1016/j.cemconres.2020.106330
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发表时间：
2021-03-01
影响因子：
11.4
通讯作者：
Pontikes, Y.
中科院分区：
文献类型：
--
作者：
Beersaerts, G.;Ascensao, G.;Pontikes, Y.
无机聚合物 (IP) 粘合剂是通过对富铁 (41 wt%) 冶金渣进行碱活化而形成的，从而形成机械性能与普通波特兰水泥粘合剂相当的材料。据报道，IP 中存在裂纹形成，这可能与体积稳定性有关，而迄今为止，IP 中的体积稳定性尚未得到充分了解。本研究测定了 IP 砂浆的自收缩和干燥收缩。单独或组合使用添加2-甲基-2,4-戊二醇（2MPL）、高炉矿渣（GGBFS）和热固化等减缓收缩策略。 IP 砂浆表现出自膨胀和高干燥收缩。添加 2MPL 导致孔隙率增加，因为空气被夹带，干燥收缩率降低了 64%。额外的热固化对 2MPL 的样品没有影响。引入 GGBFS 会导致孔隙变小，从而增加干燥收缩率。 IP 砂浆的收缩是由其孔径分布决定的，较高的收缩率导致较低的弯曲强度。
Inorganic polymer (IP) binder is formed upon alkali-activation of Fe-rich (41 wt%) metallurgical slag leading to materials with mechanical properties comparable to ordinary Portland cement binders. Crack formation is reported in IPs, which can be related to volumetric stability, which is to date not thoroughly understood in IPs. This study determined the autogenous and drying shrinkage of IP mortars. Shrinkage mitigation strategies, such as the addition of 2-methyl-2,4-pentanediol (2MPL), blast furnace slag (GGBFS), and applying heat curing, were used separately or in combination. IP mortars exhibited autogenous expansion and high drying shrinkage. The addition of 2MPL led to a porosity increase, as air was entrained, decreasing the drying shrinkage with 64%. Additional heat curing had no effect on samples with 2MPL. Introducing GGBFS resulted in smaller pores, increasing drying shrinkage. Shrinkage in IP mortars is driven by its pore size distribution and higher shrinkage resulted in lower flexural strength.