Papers by Emilija Fidanchevski
Innovative Infrastructure Solutions, 2019
Various wastes have gained attention nowaday as they are widely used in stabilization of expansiv... more Various wastes have gained attention nowaday as they are widely used in stabilization of expansive soils. The construction-demolition waste has not been widely used in soil stabilization, and its use is still under research. A lot of construction-demolition waste is being produced from old dismantled buildings whose disposal is a major concern due to limited availability of land space. This paper presents a laboratory investigation using consolidated drained triaxial test in order to study the stress-strain and volumetric behavior, shear strength parameters, strength ratio at various strain levels and stiffness of un-stabilized as well as crushed construction-demolition waste (CCDW) stabilized soil. The test results revealed that the addition of CCDW in un-stabilized soil has improved its stress-strain and volumetric behavior remarkably, at all confining pressures. The volumetric strain has been found to be decreased with the addition of CCDW. The inclusion of CCDW in unstabilized soil has decreased the cohesion value to a limited extent and increased the angle of shearing resistance significantly. An increase in strength ratio as well as the stiffness of un-stabilized soil has also been improved when it is stabilized with CCDW. In the end, a practical numerical example has been solved in order to make the readers understand the significance of the improvement in un-stabilized soil after incorporating CCDW into it. This mixture of CCDW-stabilized expansive soil can be used in construction of low-volume traffic roads and embankment stability.
Macedonian Journal of Chemistry and Chemical Engineering, Dec 20, 2021
Macedonian Journal of Chemistry and Chemical Engineering, Dec 15, 2021
Glass-ceramics were fabricated by controlled crystallization of glass vitrified without any addit... more Glass-ceramics were fabricated by controlled crystallization of glass vitrified without any additives from coal fly ash. The glass transition temperature (Tg) and peak temperature (Tp) of the parent glass were 580 ºC and 1020 ºC, respectively. The crystallization tendency of the parent glass was estimated by the Hruby-coefficient (KH = 2.3). The ratio of the crystalline and amorphous phases in the glass-ceramics sintered at 1100 ºC/60 min was 68/32. The major crystalline phases were calcium aluminum silicate (anorthite) and hematite. The density, bending strength, and E-modulus of the glass-ceramics were 2.20 g/cm 3 , 78 MPa, and 32 GPa, respectively. The glass-ceramics can potentially be used as a construction material.
MATEC web of conferences, 2023
The actual study has followed the effect of fly ash and crystalline admixture on cement mortars' ... more The actual study has followed the effect of fly ash and crystalline admixture on cement mortars' mechanical and self-healing properties. Three types of cementitious mortars composed of (i) 16 wt.% fly ash, (ii) crystalline admixture, and (iii) 16 wt.% fly ash and crystalline admixture were compared to the standard mortar (in compliance with EN 196-1). The capillary water absorption determined the sealing efficiency of the cracks over a period of time. The experimental results showed that by autogenous self-healing the standard mortar has a sealing efficiency of 40% after 28 days of treatment and 70% after 6 months of treatment, but the addition of fly ash and crystalline admixtures stimulated the autogenous selfhealing. The best results showed the mortar (iii) containing 16 wt.% fly ash and crystalline admixture, where the sealing efficiency achieved 79% after 28 days of treatment and 98% after 6 months.
Macedonian Journal of Chemistry and Chemical Engineering
Glass-ceramics were fabricated by controlled crystallization of glass vitrified without any addit... more Glass-ceramics were fabricated by controlled crystallization of glass vitrified without any additives from coal fly ash. The glass transition temperature (Tg) and peak temperature (Tp) of the parent glass were 580 ºC and 1020 ºC, respectively. The crystallization tendency of the parent glass was estimated by the Hruby-coefficient (KH = 2.3). The ratio of the crystalline and amorphous phases in the glass-ceramics sintered at 1100 ºC/60 min was 68/32. The major crystalline phases were calcium aluminum silicate (anorthite) and hematite. The density, bending strength, and E-modulus of the glass-ceramics were 2.20 g/cm3, 78 MPa, and 32 GPa, respectively. The glass-ceramics can potentially be used as a construction material.
Naturally Occurring Radioactive Materials in Construction, 2017
Abstract The cementitious materials and ceramic industries are frequently looked as targets for t... more Abstract The cementitious materials and ceramic industries are frequently looked as targets for the recycling and valorization of several wastes, residues, and by-products, generated from a wide variety of industries. In general, only technical (and chemical) aspects are covered on each attempt for recycling a waste in a particular product, while radiological features are rarely considered. This chapter aims to give new and more complete insights on the recycling of several industrial wastes, on four groups of construction materials: (1) construction materials based on Portland cements (both as cement itself and as concrete), (2) construction materials based on alkali-activated binders, (3) ceramics and glass-ceramics, and (4) gypsum. For each by-product a separate section will describe (1) the technical (and chemical) aspects of the use as part of a construction material and (2) the resulting radiological properties of the designed product, when they are available. Some ceramic industries also use radiologically active components, namely zircon and zirconia (in glazes, refractories, etc.). The radiological consequences of their production, further use/manipulation by other industrial sectors (e.g., ceramic glazes and frits production), and on the final costumers are also briefly reported.
Quality of Life (Banja Luka) - APEIRON, 2013
Fly ash, a waste by-product obtained in a thermal power plant has been a generated problem of the... more Fly ash, a waste by-product obtained in a thermal power plant has been a generated problem of the disposal all over the world. Morphological characteristics, physicochemical properties and pozzolanic activity make this waste potential material for production of ceramics. In this study high density ceramics compacts were produced by using fl y ash from the power plant REK Bitola, Republic of Macedonia. In order to increase geometrical factor of activity, the mechanical activation of the fl y ash was applied. The process of optimization of the main process parameters is conducted, such as time of mechanical activation, sintering temperature and heating rate and their interactions on the properties of obtained dense ceramic porosity and bending strength as a response function. The optimization was performed through application of 3D surface method and the obtained results are presented in the graphical and analytical form using "Statgraphics Centurion" software package.
Materiales De Construccion, Feb 1, 2017
The aim of this investigation was the synthesis of nanocomposite coatings based on Zn-Al layered ... more The aim of this investigation was the synthesis of nanocomposite coatings based on Zn-Al layered double hydroxides (Zn-Al LDH) and TiO 2. The Zn-Al LDH material, which acted as the catalyst support of the active TiO 2 component (in the content of 3 and 10 wt. %), was synthesized by a low super saturation co-precipitation method. The interaction between the Zn-Al LDH and the active TiO 2 component was accomplished by using vacuum evaporation prior to the mechanical activation and only by mechanical activation. The final suspension based on Zn-Al LDH and 10wt. % TiO 2 , impregnated only by mechanical activation, showed the optimal characteristics from the aspect of particle size distribution and XRD analysis. These properties had a positive effect on the functional properties of the coatings (photocatalytic activity and self-cleaning efficiency) after the water rinsing procedure.
Materiales de Construcción, 2019
Fly ash and phosphogypsum were used as Naturally Occurring Radioactive Materials (NORM) by-produc... more Fly ash and phosphogypsum were used as Naturally Occurring Radioactive Materials (NORM) by-products for the synthesis of belite-sulfoaluminate clinkers. The influence of raw mixture composition and firing temperature was investigated. Clinkers and cements were examined by X-ray powder diffraction and scanning electron microscopy with energy dispersive X-ray spectroscopy. The compressive strength of the cements was determined after 28 days. Clinker phases identified included ye’elimite, ß-phase of belite, ternesite and gehlenite, while the main hydration product of the cement pastes was ettringite. The results showed that belite-sulfoaluminate cements can be fabricated with a compressive strength of 45.9 N/mm2 by firing the raw mixture (70 wt.% marl, 10 wt.% bauxite and 20 wt.% phosphogypsum) at a temperature of 1320°C/1h.
Macedonian Journal of Chemistry and Chemical Engineering
The project: Al-rich industrial residues for mineral binders in the ESEE region-RIS ALiCE in the ... more The project: Al-rich industrial residues for mineral binders in the ESEE region-RIS ALiCE in the frame of the European Institute of Innovation and Technology, Raw materials (EIT-Raw Materials) co-financed by Horizon 2020/ Europe started on March 2019 and will end on February 2022. The “RIS-ALiCE” consortium consists of partners experienced in the relevant field from seven countries (SIovenia, Bosnia and Hercegovina, North Macedonia, Serbia, Hungary, Austria and France). Slovenian National Building and Civil Engineering Institute, Ljubljana, Slovenia coordinates the project.
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Papers by Emilija Fidanchevski