Sürdürülebilir Kalkınma Amaçları
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- MakaleYalnız künye2026Scopus SJRQ1High-temperature, freeze–thaw, and sulfate resistance of mortars incorporating ternary blends of fly ash, chromite, and waste glass
Gülmez, Nihan; Kanellopoulos, Antonios
The demand for sustainable construction materials promotes the use of industrial waste in cement-based systems. This study examines mortars incorporating fly ash (FA) (0%, 7.5%, and 15%), waste glass, and chromite aggregates for mechanical and durability performance. Specimens underwent compressive strength, freeze–thaw, high-temperature, sulfate attack, and ultrasonic pulse velocity tests, while microstructure was characterized by x-ray diffraction, thermogravimetric analysis, and scanning electron microscopy–energy-dispersive spectroscopy. Mortars with 7.5% FA exhibited relatively high compressive strength and improved freeze–thaw resistance. The combined use of chromite and FA improved strength retention at 800°C, reaching 23 MPa with 7.5% FA and 50% chromite. The greatest sulfate resistance occurred in mortars containing 15% FA and 15% waste glass, maintaining compressive strengths of 61 and 70.9 MPa after MgSO4 and Na2SO4 exposure, respectively.
- MakaleAçık Erişim2024Scopus SJRQ1Effect of White-Portland cement containing micro and nano silica on the mechanical and freeze-thaw properties of self compacting mortars
Etli, Serkan; Yılmaz, Tekin; Hansu, Osman
This study concentrated to investigate the influences of white-Portland cement (W-PC) containing silica fume (SF: micro-silica (µSi) and nano-silica (nSi)) as replacement (2–4 wt%) on mechanical (strength and durability), physical and microstructural behaviors of self-compacting mortars (SCMs) fabricated at 0.48–0.63 w/b ratios. In keeping with these purposes, besides of carrying out the workability (mini-slump flow: M−SF and V-funnel: V-F) experiments of SCMs, the mechanical and microstructural tests implemented were: unconfined compressive strength (UCS), flexural strength (FS), freeze–thaw (F-T) and scanning electron microscope (SEM) analysis. The outcomes displayed that, in comparison with the control, replacing W-PC by SF (particularly nSi) enhanced the UCS and FS, resisted against F-T durability by lowering the strength losses in UCS and FS. The ameliorated microstructure resulting in a reduction in the number and/or a narrowing in the size of micro-cracks and pores contributed to generate a more compact and consolidated SCM structure for the improving of strength and durability due of pore-filling effect and superior pozzolanic characteristics of µSi and especially nSi, this in turn reduced the permeability of SCM, which has a significant effect on the strength and durability behaviors of the SCM.
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İncele - MakaleYalnız künye2021Scopus SJRQ1Effect of pumice powder and artificial lightweight fine aggregate on self-compacting mortar
Etli, Serkan; Cemalgil, Selim; Onat, Onur
An experimental program was conducted to investigate the fresh properties, mechanical properties and durability characteristics of the self-compacting mortars (SCM) produced with pumice powder and Artificial Lightweight Fine Aggregate (aLWFA). aLWFA was produced by using fly ash. A total of 16 different mixtures were designed with a constant water-binder ratio of 0.37, in which natural sands were partially replaced with aLWFA and pumice powder at different volume fractions of 5%, 10% and 15%. The artificial lightweight aggregates used in this study were manufactured through cold bonding pelletisation of 90% of class-F fly ash and 10% of Portland cement in a tilted pan with an ambient temperature and moisture content. Flowability tests were conducted on the fresh mortar mixtures beforehand, to determine the self-compacting characteristics on the basis of EFNARC. To determine the conformity of the fresh mortar characteristics with the standards, mini-slump and mini-V-funnel tests were carried out. Hardened state tests were conducted after 7, 28 and 56 days to determine the flexural strength and axial compressive strength respectively. Durability, sorptivity, permeability and density tests were conducted at the end of 28 days of curing time. The test results showed that the pumice powder replacement improved both the fresh state and the hardened state characteristics of the mortar and the optimum mixture ratio was determined as 15%, considering other studies in the literature. In the aLWFA mixtures used, the mechanical and durability characteristics of the modified compositions were very close to the control mixture. It is concluded in this study that mixtures with pumice powder replacement eliminated the negative effects of the aLWFA in the mortars and made a positive contribution.
AtıfScopus16WoS15OpenAlex17İncele