Figmig Robert, Estokova Adriana, Luptak Miloslav
Faculty of Civil Engineering, Institute of Environmental Engineering, Technical University of Kosice, 04200 Kosice, Slovakia.
Faculty of Materials, Metallurgy and Recycling, Institute of Materials and Quality Engineering, Technical University of Kosice, 04200 Kosice, Slovakia.
Materials (Basel). 2021 Mar 16;14(6):1448. doi: 10.3390/ma14061448.
This experimental study focuses on the assessment of mineral additives and their incorporation into cement composites (CC). The assessment was based on a holistic approach to the performance of the durability properties of CC. Environmental suitability was also taken into consideration. In the experiments, cement pastes with w/c ratios of 0.3, 0.4, and 0.5, respectively, were prepared. Natural zeolite (NZ) and densified silica fume (SF) at doses of 7.5 and 15.0 wt.% of cement were used as the investigated (replacement) materials. Their effects (including development over time) on density, strength (flexural and compressive), porosity by water absorption, permeability by rapid chloride penetration (RCP) test, phase content by thermal analysis, and hydration progression, were observed. The results were then used to propose an evaluation approach. Natural zeolite was used for its known pozzolanic activity and classification as a supplementary cementitious material (SCM). In contrast SF acted as a filler in cement pastes, and thus did not have a direct positive effect on durability. The concept of comprehensive analysis for unknown additive classification is proposed to expressly differentiate between SCM, inert, and improving mineral additive. This concept could be applied to the assessment of mineral additives with regards to the durability and suitability of cement composites.
本实验研究聚焦于矿物添加剂及其在水泥基复合材料(CC)中的掺入情况。该评估基于对水泥基复合材料耐久性性能的整体考量方法。同时也考虑了环境适用性。在实验中,分别制备了水灰比为0.3、0.4和0.5的水泥净浆。将水泥用量7.5%和15.0%的天然沸石(NZ)和硅灰(SF)用作研究(替代)材料。观察了它们对密度、强度(抗折和抗压)、吸水率孔隙率、快速氯离子渗透(RCP)试验渗透率、热分析相含量以及水化进程的影响(包括随时间的发展情况)。然后利用这些结果提出了一种评估方法。天然沸石因其已知的火山灰活性以及作为辅助胶凝材料(SCM)的分类而被使用。相比之下,硅灰在水泥净浆中起填充作用,因此对耐久性没有直接的积极影响。提出了用于未知添加剂分类的综合分析概念,以明确区分辅助胶凝材料、惰性和改善型矿物添加剂。该概念可应用于评估矿物添加剂对水泥基复合材料耐久性和适用性的影响。