Eleftherios Anastasiou | Aristotle University of Thessaloniki (original) (raw)

Papers by Eleftherios Anastasiou

Materials proceedings, Oct 22, 2021

This article is an open access article distributed under the terms and conditions of the Creative... more This article is an open access article distributed under the terms and conditions of the Creative Commons Attribution (CC BY

Environmental sciences proceedings, Aug 14, 2020

The purpose of the present work was to study the corrosion protection that relatively lowcost mag... more The purpose of the present work was to study the corrosion protection that relatively lowcost magnesium hydroxide coatings offer to concrete by stabilizing the surface pH. To facilitate the material's adhesive ability, methyl-cellulose and carboxymethyl-cellulose were used as environmentally friendly additives in three different concentrations, 1, 0.4 and 0.1 wt.% of solids, respectively. The coatings were applied on the surface of concrete blocks, in two different coating thicknesses. A sulfuric acid solution was used to simulate the biologically produced acid in sewer pipes. Sulfuric acid was sprayed on the specimens, while the total amount of acid sprayed was calculated, in order to correspond to a specific reaction's stoichiometry daily. The surface pH of coated specimens was monitored daily with a surface pH meter. The gypsum production was studied with X-ray diffraction, to evaluate the coatings' protection. The experimental time period that coatings were consumed was compared with the theoretically consumption time.

Springer eBooks, Sep 22, 2007

Construction and Building Materials, Nov 1, 2020

This paper introduces McKnight's (p; gO-regularity and (p; q) radicals, a collection of radicals ... more This paper introduces McKnight's (p; gO-regularity and (p; q) radicals, a collection of radicals which contains the Jacobson radical and the radicals of regularity and strong regularity among its members. The linear semiprime (p; q) radicals are classified canonically and, as a result of this classification, these radicals can be distinguished by the fields GF(p) and are shown to form a lattice. The semiprime (p; q) radicals are found to be hereditary and the linear semiprime (p; q) radical of a complete matrix ring of a ring R is determined to be the complete matrix ring over the (p; q) radical of R. More generally, the (p; q) radical of a complete matrix ring over R is contained in the matrix ring over the (p; q) radical of R for all (p; q) radicals.

Steel Slags are by-products of Steel Industry using the Electric Arc Furnace method for steelmaki... more Steel Slags are by-products of Steel Industry using the Electric Arc Furnace method for steelmaking. This methodology is widely used in South Europe where the research on steel slag applications in concrete has been developed. In this paper, the properties in fresh and hardened state of concrete for pavements are described as well as a pilot application of steel slag concrete in road pavement. Based on the results it is obvious that the use of steel slags in pavement application is very advantageous from technical point of view. Basic desirable characteristics are enhanced or significantly increased, such as the compressive strength, ductility and resistance to abrasion. Furthermore, the anti slipping properties of the pavements are considerably enhanced. A comparison of conventional concrete pavement with steel slag concrete is made based on the cost and environmental footprint considerations, taking into account the maintenance cost during the service life of the pavement.

Materials, Jan 8, 2021

This article is an open access article distributed under the terms and conditions of the Creative... more This article is an open access article distributed under the terms and conditions of the Creative Commons Attribution (CC BY

Resources Conservation and Recycling, Aug 1, 2015

ABSTRACT The construction industry is a major consumer of natural resources and a major contribut... more ABSTRACT The construction industry is a major consumer of natural resources and a major contributor to CO2 emissions. As increasing attention is paid to sustainability and resource preservation, current construction practices need to be assessed in terms of environmental performance as well. Currently, the decision making process for pavement construction in Greece is largely based on initial cost, excluding use and maintenance costs as well as environmental performance. Therefore, the use of concrete road pavements is very limited, despite possible technical and financial benefits. In the present paper, a comparative life cycle assessment was carried out for six different concrete road pavements. The parameters for the comparative LCA were three types of binders; a pozzolanic Portland cement, a new hydraulic road binder and a mixed-type binder consisting of Portland cement and fly ash, as well as two different aggregates; crushed limestone and steel slag. Construction, use and maintenance and end-of-life recycling for a period of 40 years were considered for the life cycle assessment. Results show that concrete road pavements with high volume of alternative materials can reduce CO2-eq emissions to a great extent compared to ordinary concrete pavements and, thus, significantly improve their environmental footprint. The transportation distance sensitivity analysis showed that substituting cement with fly ash is environmentally beneficial even when fly ash is transported over long distances, while the emissions from the use of alternative aggregates in concrete are reduced only in limited geographical areas.

Materials and Structures, Jun 1, 2022

Construction and Building Materials, 2014

ABSTRACT An experimental program was carried out in order to investigate the possibility of produ... more ABSTRACT An experimental program was carried out in order to investigate the possibility of producing concrete incorporating large volumes of industrial by-products and secondary materials. The alternative materials tested were fly ash as binder for cement replacement, recycled fine aggregate originating from mixed construction and demolition waste and steel slag as coarse aggregate. Several mortar and concrete mixtures were prepared using different aggregate and binder combinations in order to identify the feasibility of producing concrete with maximum use of alternative materials. The different mixtures were tested for mechanical strength at different ages, while durability measurements such as chloride ion penetration and freeze–thaw resistance were also carried out. The results showed that the use of fine construction and demolition waste aggregate increases porosity in concrete and also reduces strength and durability, while its combination with steel slag aggregate partly recovers strength and durability loss. Concrete with mixed construction and demolition waste as fine aggregate and steel slag as coarse aggregate reached 30 MPa 28-day compressive strength and showed adequate durability for low grade applications. Also, 50% cement replacement with high calcium fly ash and use only of steel slag and recycled aggregates resulted in concrete of adequate strength and considerable environmental gains.

Springer eBooks, Sep 22, 2007

Waste Management, Dec 1, 2014

The increasing awareness of the society about safe guarding heritage buildings and at the same ti... more The increasing awareness of the society about safe guarding heritage buildings and at the same time protecting the environment promotes strategies of combining principles of restoration with environmentally friendly materials and techniques. Along these lines, an experimental program was carried out in order to investigate the possibility of producing repair, lime-based mortars used in historic buildings incorporating secondary materials. The alternative material tested was recycled fine aggregates originating from mixed construction and demolition waste. Extensive tests on the raw materials have been performed and mortar mixtures were produced using different binding systems with natural, standard and recycled sand in order to compare their mechanical, physical and microstructure properties. The study reveals the improved behavior of lime mortars, even at early ages, due to the reaction of lime with the Al and Si constituents of the fine recycled sand. The role of the recycled sand was more beneficial in lime mortars rather than the lime-pozzolan or lime-pozzolan-cement mortars as a decrease in their performance was recorded in the latter cases due to the mortars' structure.

Construction and Building Materials, Dec 1, 2021

Rheological and mechanical properties as well as long term volume stability seem to be the target... more Rheological and mechanical properties as well as long term volume stability seem to be the target characteristics in developing SCC for concrete applications. Calcareous fly ash as mineral admixture in concrete mixtures often increases water demand for a required consistency. This does not favor the proportioning of SCC with this fly ash since viscous mixtures of low mobility are produced. However, calcareous fly ash exhibits noticeable self-cementing capacity and could replace a high volume of Portland cement. In this experimental work, a calcareous fly ash replaced cement in different proportions up to 50% by mass and the effects on rheological properties and mechanical characteristics were measured, as well as shrinkage deformations. All necessary modifications in proportioning and mixing are also mentioned. Based on the results, the production of SCC of adequate 28-day strength (50 MPa) with high volume calcareous fly ash can be achieved.

ABSTRACT The objectives of the presented research work were to check the suitability of steel sla... more ABSTRACT The objectives of the presented research work were to check the suitability of steel slags for concrete production and then to develop concrete mixtures with high volume of industrial by-products, for low-cost and environmentally friendly applications. Electric arc furnace slag (EAFS) was tested and used as a concrete aggregate, and ladle furnace slag –raw or processed by grinding– as a supplementary cementing material. Furthermore, EAFS concrete mixtures were developed and tested in the laboratory for use in heavy-traffic road pavements or in high-requirements industrial floors. A 500 m long pilot road pavement serving a ready-mix concrete plant was constructed with EAFS concrete. A survey conducted on the road after ten years of continuous use showed that it performed in an excellent way. Based on results, it seems that concrete mixtures with high-volume of industrial by-products (EAFS aggregates and cementitious materials) can be produced meeting high-strength requirements, up to 70 MPa, and durability issues for application in road pavements, airport or marine port fields, paving blocks or industrial floors. Ladle furnace slag (LFS) was investigated in order to determine its cementitious and pozzolanic character in regard to its granulometry. Chemical composition and particle size distribution measurements were also performed. Volume stability was also tested in mortar mixtures. This investigation proved that LFS is a weak cementing material but by using the finer fragments or by grinding, its binding properties are considerably enhanced. Grinding also seems to be more effective for enhancing strength potential. Mortar mixtures in which 20% of cement (wt.-%) was replaced by LFS developed 2 90-95% of the reference mortar strength. A pilot production of shotcrete with LFS proved very successful. The positive research results encouraged the largest steel industry in Greece to invest on establishing a subsidiary company for exploiting steel by-products, which are not yet characterized as waste but are recycled in construction, contributing to the protection of the environment and to the competitiveness of the steel industry sector.

ABSTRACT The construction industry is a major consumer of natural resources and a major contribut... more ABSTRACT The construction industry is a major consumer of natural resources and a major contributor to CO2 emissions. As increasing attention is paid to sustainability and resource preservation, current construction practices need to be assessed in terms of environmental performance as well. Currently, the decision making process for pavement construction in Greece is largely based on initial cost, excluding use and maintenance costs as well as environmental performance. Therefore, the use of concrete road pavements is very limited, despite possible technical and financial benefits. In the present paper, a comparative life cycle assessment was carried out for six different concrete road pavements. The parameters for the comparative LCA were three types of binders; a pozzolanic Portland cement, a new hydraulic road binder and a mixed-type binder consisting of Portland cement and fly ash, as well as two different aggregates; crushed limestone and steel slag. Construction, use and maintenance and end-of-life recycling for a period of 40 years were considered for the life cycle assessment. Results show that concrete road pavements with high volume of alternative materials can reduce CO2-eq emissions to a great extent compared to ordinary concrete pavements and, thus, significantly improve their environmental footprint. The transportation distance sensitivity analysis showed that substituting cement with fly ash is environmentally beneficial even when fly ash is transported over long distances, while the emissions from the use of alternative aggregates in concrete are reduced only in limited geographical areas.

Materials proceedings, Oct 22, 2021

This article is an open access article distributed under the terms and conditions of the Creative... more This article is an open access article distributed under the terms and conditions of the Creative Commons Attribution (CC BY

Environmental sciences proceedings, Aug 14, 2020

The purpose of the present work was to study the corrosion protection that relatively lowcost mag... more The purpose of the present work was to study the corrosion protection that relatively lowcost magnesium hydroxide coatings offer to concrete by stabilizing the surface pH. To facilitate the material's adhesive ability, methyl-cellulose and carboxymethyl-cellulose were used as environmentally friendly additives in three different concentrations, 1, 0.4 and 0.1 wt.% of solids, respectively. The coatings were applied on the surface of concrete blocks, in two different coating thicknesses. A sulfuric acid solution was used to simulate the biologically produced acid in sewer pipes. Sulfuric acid was sprayed on the specimens, while the total amount of acid sprayed was calculated, in order to correspond to a specific reaction's stoichiometry daily. The surface pH of coated specimens was monitored daily with a surface pH meter. The gypsum production was studied with X-ray diffraction, to evaluate the coatings' protection. The experimental time period that coatings were consumed was compared with the theoretically consumption time.

Springer eBooks, Sep 22, 2007

Construction and Building Materials, Nov 1, 2020

This paper introduces McKnight's (p; gO-regularity and (p; q) radicals, a collection of radicals ... more This paper introduces McKnight's (p; gO-regularity and (p; q) radicals, a collection of radicals which contains the Jacobson radical and the radicals of regularity and strong regularity among its members. The linear semiprime (p; q) radicals are classified canonically and, as a result of this classification, these radicals can be distinguished by the fields GF(p) and are shown to form a lattice. The semiprime (p; q) radicals are found to be hereditary and the linear semiprime (p; q) radical of a complete matrix ring of a ring R is determined to be the complete matrix ring over the (p; q) radical of R. More generally, the (p; q) radical of a complete matrix ring over R is contained in the matrix ring over the (p; q) radical of R for all (p; q) radicals.

Steel Slags are by-products of Steel Industry using the Electric Arc Furnace method for steelmaki... more Steel Slags are by-products of Steel Industry using the Electric Arc Furnace method for steelmaking. This methodology is widely used in South Europe where the research on steel slag applications in concrete has been developed. In this paper, the properties in fresh and hardened state of concrete for pavements are described as well as a pilot application of steel slag concrete in road pavement. Based on the results it is obvious that the use of steel slags in pavement application is very advantageous from technical point of view. Basic desirable characteristics are enhanced or significantly increased, such as the compressive strength, ductility and resistance to abrasion. Furthermore, the anti slipping properties of the pavements are considerably enhanced. A comparison of conventional concrete pavement with steel slag concrete is made based on the cost and environmental footprint considerations, taking into account the maintenance cost during the service life of the pavement.

Materials, Jan 8, 2021

This article is an open access article distributed under the terms and conditions of the Creative... more This article is an open access article distributed under the terms and conditions of the Creative Commons Attribution (CC BY

Resources Conservation and Recycling, Aug 1, 2015

ABSTRACT The construction industry is a major consumer of natural resources and a major contribut... more ABSTRACT The construction industry is a major consumer of natural resources and a major contributor to CO2 emissions. As increasing attention is paid to sustainability and resource preservation, current construction practices need to be assessed in terms of environmental performance as well. Currently, the decision making process for pavement construction in Greece is largely based on initial cost, excluding use and maintenance costs as well as environmental performance. Therefore, the use of concrete road pavements is very limited, despite possible technical and financial benefits. In the present paper, a comparative life cycle assessment was carried out for six different concrete road pavements. The parameters for the comparative LCA were three types of binders; a pozzolanic Portland cement, a new hydraulic road binder and a mixed-type binder consisting of Portland cement and fly ash, as well as two different aggregates; crushed limestone and steel slag. Construction, use and maintenance and end-of-life recycling for a period of 40 years were considered for the life cycle assessment. Results show that concrete road pavements with high volume of alternative materials can reduce CO2-eq emissions to a great extent compared to ordinary concrete pavements and, thus, significantly improve their environmental footprint. The transportation distance sensitivity analysis showed that substituting cement with fly ash is environmentally beneficial even when fly ash is transported over long distances, while the emissions from the use of alternative aggregates in concrete are reduced only in limited geographical areas.

Materials and Structures, Jun 1, 2022

Construction and Building Materials, 2014

ABSTRACT An experimental program was carried out in order to investigate the possibility of produ... more ABSTRACT An experimental program was carried out in order to investigate the possibility of producing concrete incorporating large volumes of industrial by-products and secondary materials. The alternative materials tested were fly ash as binder for cement replacement, recycled fine aggregate originating from mixed construction and demolition waste and steel slag as coarse aggregate. Several mortar and concrete mixtures were prepared using different aggregate and binder combinations in order to identify the feasibility of producing concrete with maximum use of alternative materials. The different mixtures were tested for mechanical strength at different ages, while durability measurements such as chloride ion penetration and freeze–thaw resistance were also carried out. The results showed that the use of fine construction and demolition waste aggregate increases porosity in concrete and also reduces strength and durability, while its combination with steel slag aggregate partly recovers strength and durability loss. Concrete with mixed construction and demolition waste as fine aggregate and steel slag as coarse aggregate reached 30 MPa 28-day compressive strength and showed adequate durability for low grade applications. Also, 50% cement replacement with high calcium fly ash and use only of steel slag and recycled aggregates resulted in concrete of adequate strength and considerable environmental gains.

Springer eBooks, Sep 22, 2007

Waste Management, Dec 1, 2014

The increasing awareness of the society about safe guarding heritage buildings and at the same ti... more The increasing awareness of the society about safe guarding heritage buildings and at the same time protecting the environment promotes strategies of combining principles of restoration with environmentally friendly materials and techniques. Along these lines, an experimental program was carried out in order to investigate the possibility of producing repair, lime-based mortars used in historic buildings incorporating secondary materials. The alternative material tested was recycled fine aggregates originating from mixed construction and demolition waste. Extensive tests on the raw materials have been performed and mortar mixtures were produced using different binding systems with natural, standard and recycled sand in order to compare their mechanical, physical and microstructure properties. The study reveals the improved behavior of lime mortars, even at early ages, due to the reaction of lime with the Al and Si constituents of the fine recycled sand. The role of the recycled sand was more beneficial in lime mortars rather than the lime-pozzolan or lime-pozzolan-cement mortars as a decrease in their performance was recorded in the latter cases due to the mortars' structure.

Construction and Building Materials, Dec 1, 2021

Rheological and mechanical properties as well as long term volume stability seem to be the target... more Rheological and mechanical properties as well as long term volume stability seem to be the target characteristics in developing SCC for concrete applications. Calcareous fly ash as mineral admixture in concrete mixtures often increases water demand for a required consistency. This does not favor the proportioning of SCC with this fly ash since viscous mixtures of low mobility are produced. However, calcareous fly ash exhibits noticeable self-cementing capacity and could replace a high volume of Portland cement. In this experimental work, a calcareous fly ash replaced cement in different proportions up to 50% by mass and the effects on rheological properties and mechanical characteristics were measured, as well as shrinkage deformations. All necessary modifications in proportioning and mixing are also mentioned. Based on the results, the production of SCC of adequate 28-day strength (50 MPa) with high volume calcareous fly ash can be achieved.

ABSTRACT The objectives of the presented research work were to check the suitability of steel sla... more ABSTRACT The objectives of the presented research work were to check the suitability of steel slags for concrete production and then to develop concrete mixtures with high volume of industrial by-products, for low-cost and environmentally friendly applications. Electric arc furnace slag (EAFS) was tested and used as a concrete aggregate, and ladle furnace slag –raw or processed by grinding– as a supplementary cementing material. Furthermore, EAFS concrete mixtures were developed and tested in the laboratory for use in heavy-traffic road pavements or in high-requirements industrial floors. A 500 m long pilot road pavement serving a ready-mix concrete plant was constructed with EAFS concrete. A survey conducted on the road after ten years of continuous use showed that it performed in an excellent way. Based on results, it seems that concrete mixtures with high-volume of industrial by-products (EAFS aggregates and cementitious materials) can be produced meeting high-strength requirements, up to 70 MPa, and durability issues for application in road pavements, airport or marine port fields, paving blocks or industrial floors. Ladle furnace slag (LFS) was investigated in order to determine its cementitious and pozzolanic character in regard to its granulometry. Chemical composition and particle size distribution measurements were also performed. Volume stability was also tested in mortar mixtures. This investigation proved that LFS is a weak cementing material but by using the finer fragments or by grinding, its binding properties are considerably enhanced. Grinding also seems to be more effective for enhancing strength potential. Mortar mixtures in which 20% of cement (wt.-%) was replaced by LFS developed 2 90-95% of the reference mortar strength. A pilot production of shotcrete with LFS proved very successful. The positive research results encouraged the largest steel industry in Greece to invest on establishing a subsidiary company for exploiting steel by-products, which are not yet characterized as waste but are recycled in construction, contributing to the protection of the environment and to the competitiveness of the steel industry sector.

ABSTRACT The construction industry is a major consumer of natural resources and a major contribut... more ABSTRACT The construction industry is a major consumer of natural resources and a major contributor to CO2 emissions. As increasing attention is paid to sustainability and resource preservation, current construction practices need to be assessed in terms of environmental performance as well. Currently, the decision making process for pavement construction in Greece is largely based on initial cost, excluding use and maintenance costs as well as environmental performance. Therefore, the use of concrete road pavements is very limited, despite possible technical and financial benefits. In the present paper, a comparative life cycle assessment was carried out for six different concrete road pavements. The parameters for the comparative LCA were three types of binders; a pozzolanic Portland cement, a new hydraulic road binder and a mixed-type binder consisting of Portland cement and fly ash, as well as two different aggregates; crushed limestone and steel slag. Construction, use and maintenance and end-of-life recycling for a period of 40 years were considered for the life cycle assessment. Results show that concrete road pavements with high volume of alternative materials can reduce CO2-eq emissions to a great extent compared to ordinary concrete pavements and, thus, significantly improve their environmental footprint. The transportation distance sensitivity analysis showed that substituting cement with fly ash is environmentally beneficial even when fly ash is transported over long distances, while the emissions from the use of alternative aggregates in concrete are reduced only in limited geographical areas.