Browsing by Author "Argin, Gizem"

Now showing 1 - 2 of 2

Compatibility of Superplasticizers With Natural Pozzolan Blended Cement: Multi-Criteria Compatibility Index Through Rheology and Hydration Kinetics
(Taylor & Francis Ltd, 2025) Argin, Gizem; Uzal, Burak
An effective technique to decrease carbon dioxide emissions in the cement industry is the partial replacement of clinker with supplemental cementitious materials (SCMs). Given the restricted supply of by-product SCMs such fly ash, blast furnace slag, and silica fume, natural pozzolans provide viable options in the manufacturing of blended cement. In cementitious systems with natural pozzolans, the use of superplasticizers is essential to compensate for the reduced workability caused by their higher water demand. This study investigates the compatibility of different superplasticizer types, administered at similar dosages, with Portland cement containing 40% natural pozzolan, focusing on paste rheology and hydration kinetics. A Multi-Criteria Compatibility Index (MCCI) was created to provide a comprehensive and quantitative evaluation of compatibility between natural pozzolans and different types of superplasticizers, utilizing rheological and hydration kinetics within a weighted scoring framework. The assessment findings indicated that PMS displayed the best overall compatibility, principally owing to its improved hydration properties, but PNS revealed enhanced performance in rheological characteristics. PCA demonstrated restricted compatibility in both categories. The MCCI framework delivered a balanced and thorough comparison unattainable by single-parameter studies, providing a solid methodological foundation for future study on SCM-admixture compatibility.
Citation - WoS: 11
Citation - Scopus: 13
Effect of Duration and Type of Grinding on the Particle Size Distribution and Microstructure of Natural Pumice With Low Pozzolanic Reactivity
(Elsevier, 2023) Taj, Khalilullah; Ilcan, Huseyin; Teksin, Eray; Argin, Gizem; Ardog, Mehmet Kemal; Uzal, Burak; Sahmaran, Mustafa; Ardoğa, Mehmet Kemal
Pumice, with low pozzolanic reactivity, was ground for 1, 3, and 6 h with a laboratory ball mill in dry conditions and it was ground for 1 h in wet conditions via an industrial-scale ball mill. Based on derivative particle dis-tribution, grinding for longer periods led to the disappearance of bimodal distribution and the development of unimodal distribution. Furthermore, the phase characterization, assessed through XRD, demonstrated appre-ciable changes in intensities of the peaks of quartz and dachiardite. The extension of grinding time resulted in a significant uptake at the early-age lime consumption and evolution of hydration heat. According to SEM images, the number of particles between 10 and 20 & mu;m was less in the powder ground for 3 and 6 h. Moreover, it was found that the prismatic shapes of raw pumice tended to transform to spheroid shapes after prolonged grinding, and the smooth surfaces of pumice particles became more rugged.