Escuela Técnica Superior de Ingenieros de Minas y Energía, Universidad Politécnica de Madrid, Calle Ríos Rosas 21, 28003 Madrid, Spain.
Laboratorio Oficial para Ensayos de Materiales de Construcción-LOEMCO, Calle Eric Kandel 1, 28906 Madrid, Spain.
Molecules. 2021 Sep 2;26(17):5348. doi: 10.3390/molecules26175348.
This work presents the results of the study of the physical, chemical, mineralogical and pozzolanic properties of the altered volcanic tuffs (AVT) that lie in the Los Frailes caldera, south of the Iberian Peninsula, and demonstrates their qualities as pozzolans for the manufacturing of mortars and pozzolanic cements of high mechanical strength. The main objective of this research is to show to what extent the AVTs can replace portland cement (PC) in mortars, with standardised proportions of 75:25% and 70:30% (PC-AVT). To achieve these objectives, three AVT samples were studied by a petrographic analysis of thin section (PATS), DRX, FRX and MEB. The pozzolanic properties were determined by three methods: electrical conductivity (ECT), chemical pozzolanicity tests (CPT) at 8 and 15 days and mechanical strength tests (MS) of the specimens at 2, 7, 28 and 90 days. Studies of a PATS, DRX, FRX and MEB showed that the AVT samples' constitutions are complex where smectite (montmorillonite), mordenite, quartz, halloysite, illite, kaolinite, volcanic glass and lithic fragments coexist. The results of the ECT and CPT tests confirmed the pozzolanic properties of the samples analysed and proved an increase in mechanical strength from 2 to 90 days of testing.
本工作展示了对伊比利亚半岛南部 Los Frailes 火山口处变质火山凝灰岩（AVT）的物理、化学、矿物和火山灰特性的研究结果，并证明了它们作为制造具有高机械强度的砂浆和火山灰水泥的火山灰的特性。这项研究的主要目的是表明 AVT 在多大程度上可以替代波特兰水泥（PC）在砂浆中的应用，其标准比例为 75:25%和 70:30%（PC-AVT）。为了实现这些目标，对三个 AVT 样本进行了岩相分析薄片（PATS）、DRX、FRX 和 MEB 的研究。火山灰特性通过三种方法确定：电导率（ECT）、8 天和 15 天的化学火山灰活性测试（CPT）以及 2、7、28 和 90 天的试件机械强度测试（MS）。PATS、DRX、FRX 和 MEB 的研究表明，AVT 样本的组成非常复杂，其中共存有蒙脱石（蒙脱石）、丝光沸石、石英、埃洛石、伊利石、高岭石、火山玻璃和岩屑。ECT 和 CPT 测试的结果证实了所分析样品的火山灰特性，并证明了机械强度从 2 天到 90 天测试的增加。
