Ina Pundiene - Academia.edu (original) (raw)

Papers by Ina Pundiene

Research paper thumbnail of Lightweight Ceramics with Admixtures of Mineral-Wool Production Waste and Aluminum Silicate Cenospheres of Various Fractions

Glass and Ceramics, 2022

The effect of admixtures of aluminosilicate cenospheres (ASC) of two fractions on the structure a... more The effect of admixtures of aluminosilicate cenospheres (ASC) of two fractions on the structure and properties of ceramic with waste from the production of mineral wool (MW) was investigated. The influence of different amounts (from 10 to 30%) and different fractions (0.125 – 0.250 mm) and < 0.125 mm ASC on the physical and mechanical properties of ceramic samples after firing at 1000 – 1080°C was determined. It was found that a strong lightweight ceramic with low shrinkage and high porosity can be obtained by using MW as a leaner additive in combination with ASC of two different fractions.

Research paper thumbnail of The influence of calcium nitrate on setting and hardening rate of Portland cement concrete at different temperatures

IOP Conference Series: Materials Science and Engineering, 2017

Calcium nitrate in mortars and concrete is used as a multifunctional additive: as set accelerator... more Calcium nitrate in mortars and concrete is used as a multifunctional additive: as set accelerator, plasticizer, long term strength enhancer and as antifreeze admixture. Used binding material and the amount of calcium nitrate, affect the characteristics of the concrete mixture and strength of hardened concrete. The setting time of the initial and the final binding at different temperatures of hardening (+ 20 °C and + 5 °C) of the pastes made of different cements (Portland cement CEM I 42.5 R and Portland limestone cement CEM II/A-LL 42.5 R) and various amounts of calcium nitrate from 1 % until 3 % were investigated. The effect of calcium nitrate on technological characteristics of concrete mixture (the consistency of the mixture, the density, and the amount of air in the mixture), on early concrete strength after 2 and 7 days, as well as on standard concrete strength after 28 days at different temperatures (at + 20 °C and + 5 °C) were analysed.

Research paper thumbnail of The impact of expanded polystyrene waste of different fineness on the properties of lightweight composite

IOP Conference Series: Materials Science and Engineering, 2019

Expanded polystyrene (EP) is widely used as a packaging material for many types of goods. However... more Expanded polystyrene (EP) is widely used as a packaging material for many types of goods. However, once the material is used, it is disposed of in landfills, where it can remain intact for the lifetime of several generations. Recycling of disposed EP packaging is of high relevance worldwide. The main objective of this study is to make a more detailed research into the effect of EP aggregate waste of different fineness and shape on physical and mechanical properties of porous lightweight aggregates concrete (PLWAC) with EP waste aggregates. Tests were done with Portland cement, EP waste of different fractions, resulted from crushing (EPR) and cutting (EPU), metakaolin, superplasticizer and air entraining admixture. Six batches of PLWAC specimens were formed with different EPR/EPU ratios, ranging from 0.5 to 3.The change in EPR/EPU ratio in PLWAC leads to structural changes and density reduction from 550 to 410 kg/m3 after drying. When EPR/EPU ratio in the PLWAC is increased to 2, the...

Research paper thumbnail of Influence of Plasticizer Amount on Rheological and Hydration Properties of CEM II Type Portland Cements

IOP Conference Series: Materials Science and Engineering, 2015

Research paper thumbnail of The role of temperature and activator solution molarity on the viscosity and hard structure formation of geopolymer pastes

Construction and Building Materials, Feb 1, 2021

Research paper thumbnail of Impact of different types of plasticizing admixtures on the rheological properties and hydration of blended cements

Journal of Thermal Analysis and Calorimetry, Sep 11, 2015

Research paper thumbnail of The synergistic effect of adding a blend of deflocculants and microsilica on the properties of high temperature resistant lightweight concrete with cenospheres

Construction and Building Materials, 2020

Research paper thumbnail of Impact of municipal solid waste incineration bottom ash on the properties and frost resistance of clay bricks

Journal of Material Cycles and Waste Management, Oct 27, 2021

This paper presents an experimental study on the properties, structure and durability (frost resi... more This paper presents an experimental study on the properties, structure and durability (frost resistance: one-side and all-sides freezing and thawing method) of fired clay bricks containing clay and municipal solid waste incineration (MSWI) bottom ash (BA). BA is a non-hazardous substance containing mainly CaO and SiO 2 , and also a low content of heavy metals. Clay was replaced with the BA up to 15% by weight. The bricks were fired at 1000 °C temperature and maintained at the maximum heat for 1 h. According to the research data, BA addition has an effect on the structure and properties of clay bricks. Higher content of BA in the mix of clay bricks leads to the increase of water absorption and total porosity and the decrease of density, and, therefore, lowers the durability (frost resistance) of clay bricks. In clay bricks with higher BA content the typical brick surface damages start appearing after the lower number of freezing and thawing cycles (both in one-side and all-sides freezing and thawing method). Nevertheless, all samples tested for resistance to freezing and thawing in one-side method is classified as F2 class according to the LST EN 772-22:2019 standard (severe weather resistance).

Research paper thumbnail of The synergetic interaction of chemical admixtures on the properties of eco-friendly lightweight concrete from industrial technogenic waste

Construction and Building Materials, Sep 1, 2020

Research paper thumbnail of The Lightweight Porous Fine Aggregate Composite Based on Secondary Raw Materials

Key Engineering Materials, Apr 1, 2019

The main objective of this study was to carry out more detailed research on the effects of the am... more The main objective of this study was to carry out more detailed research on the effects of the amount of cement paste on the physical and mechanical properties of porous fine aggregate concrete (PFAC). Fine foamed glass aggregate (prepared of local glass breaks) and crushed expanded polystyrene aggregate (prepared of local packing tare of household equipment), ordinary Portland cement (OPC), plasticizing and air entraining admixtures, as well as pozzolanic additive – metakaolin-based waste (local waste in production process of foamed glass aggregate), were used for the preparation of forming mixtures. Fine aggregates were coated by an extremely thin layer of porous cement paste in the samples with the lowest amount of OPC (70 kg/m3), and the aggregates contact with each other mainly at the points (empty spaces between the aggregates are interconnected between each other). There were no empty spaces between the aggregates observed, and porous cement paste seems to be monolithic in the samples with the highest amount of OPC (370 kg/m3). Increased amount of OPC (from 70 to 370 kg/m3) results in denser structure, increased dry density, compressive strength, thermal conductivity coefficient and decreased water absorption of the samples.

Research paper thumbnail of The influence of carbon nanotubes on the properties of water solutions and fresh cement pastes

IOP Conference Series: Materials Science and Engineering, 2017

Research paper thumbnail of The Effect of Silica Fume Addition on the Resistance of Concrete to Alkali Silica Reaction

IOP conference series, Nov 1, 2019

Research paper thumbnail of Selection of superplasticisers for improving the rheological and mechanical properties of cement paste with CNTs

Construction and Building Materials, Aug 1, 2020

h i g h l i g h t s Electrical conductivity (EC) of SP influences cement paste temperature and vi... more h i g h l i g h t s Electrical conductivity (EC) of SP influences cement paste temperature and viscosity. EC of different type of SP affects the hydration process of cement paste with CNTs. SP type influences hydration products amount in cement paste with CNTs.

Research paper thumbnail of Experimental study of the behaviour of cement pastes in the presence of carbon nanotubes

Modern building materials, structures and techniques, Dec 3, 2019

Research paper thumbnail of The workability kinetics of phosphogypsum binder

Modern building materials, structures and techniques, Dec 3, 2019

The dihydrate phosphogypsum (PG) based binder workability kinetics were investigated regarding to... more The dihydrate phosphogypsum (PG) based binder workability kinetics were investigated regarding to waterbinder ratio (W/B) and chemical admixtures added to the composition of PG paste. PG was dried at 60 °C and homogenized to powder like particles with collision milling in disintegrator and calcium sulphate hemihydrate was obtained by heating PG at 180 °C. The obtained binder chemical, mineralogical and technological properties were tested and compared to commercial gypsum plaster. Early age (2 h) and 14 d compression strength was determined. The workability and setting time of both-PG and commercial gypsum was investigated with viscosimeter, ultrasonic pulse velocity and Vicat apparatus and correlation between testing methods was obtained. Results indicate that binder based on PG has slightly lower pH (pH 6.3) than commercial binder (pH 6.8) and finer particle size grading leading to increased W/B ratio and more rapid initial setting time. The set retarder could efficiently increase the setting time of PG binder giving extra workability time which is positive factor for prolonged treatment of binder slurry, i.e. to prepare porous gypsum binder. Such approach would give a safer alternative to PG disposal, closing the materials loop and enhancing the circularity of this material.

Research paper thumbnail of The effect of multi-walled carbon nanotubes on the rheological properties and hydration process of cement pastes

Construction and Building Materials, Nov 1, 2018

Research paper thumbnail of Influence of alkaline activator solution ratio on the properties of biomass fly ash-based alkali-activated materials

Journal of physics, 2023

This study explored the use of untreated high-carbon biomass fly ash (BFA) and less alkaline Na2C... more This study explored the use of untreated high-carbon biomass fly ash (BFA) and less alkaline Na2CO3 as an activator to create alkali-activated materials (AAM). This article investigated how the Na2CO3/Na2SiO3 (SC/SS) ratio of the alkaline activator solution (AAS) influenced the setting time, structural development and physical-mechanical properties of BFA-based AAM pastes that were cured at room temperature. With an increase in the SC/SS ratio, AAM pastes’ initial and final setting times shorten, respectively. The AAM sample with the lowest density and ultrasonic pulse velocity (UPV) value also has the maximum water absorption. The compressive strength of AAM samples dropped after 7 days of curing while the SC/SS ratio increased. Nevertheless, after 28 days of curing, the compressive strength of AAM samples rose with a rising SC/SS ratio. The results for density, water absorption, and UPV were corroborated by the scanning electron microscope (SEM) analyses, which demonstrated that when the SC/SS ratio rises, the structure of the samples gets denser and more homogeneous, in line with the increased compressive strength of the samples.

Research paper thumbnail of Flexural Behavior of Reinforced Concrete Beams Strengthened by Textile Reinforced Magnesium Potassium Phosphate Cement Mortar

Frontiers in Materials, Aug 21, 2020

Research paper thumbnail of Moisture-mechanical performance improvement of thermal insulating polyurethane using paper production waste particles grafted with different coupling agents

Construction and Building Materials, May 1, 2019

h i g h l i g h t s Titanate coupling agents reduce particle-polyol mixture viscosity more than 2... more h i g h l i g h t s Titanate coupling agents reduce particle-polyol mixture viscosity more than 2 times. Titanate coupling agents form hydrophobic monomolecular layer on the particle surface. Coupled paper waste particles increase compressive and tensile strengths. Coupled paper waste particles initiate nucleation process in particle-polyol mixture.

Research paper thumbnail of A Study of Rapeseed Oil-Based Polyol Substitution with Bio-based Products to Obtain Dimensionally and Structurally Stable Rigid Polyurethane Foam

Journal of Polymers and The Environment, Jun 9, 2018

Water-blown polyurethane foams from low functionality polyols are characterized by intensive shri... more Water-blown polyurethane foams from low functionality polyols are characterized by intensive shrinkage, high density, post blowing, and longer demold time. These drawbacks can be partially, or fully, eliminated by varying chemical parameters of the main components. Therefore, an aliphatic polyester rapeseed oil-based polyol was modified with bio-based glycerin (RGL) and propylene glycol (RPG). The impact of the molecular weight and hydroxyl value of the blends were evaluated by testing obtained bio-based polyurethane foams. Compared to RGL-based foams, RPG-modified foams had the strictest standard (EN 13165) requirements regarding dimensional stability. These foams demonstrated a reduced apparent density from 12.6 to 20.8%, a faster foam curing capability by 47%, and the shortest demold time due to the open cell structure. The RGL modified foams had better cross-linking capability, slower ageing of thermal conductivity, and an increased compressive strength of 82.7% compared to the non-modified foam.

Research paper thumbnail of Lightweight Ceramics with Admixtures of Mineral-Wool Production Waste and Aluminum Silicate Cenospheres of Various Fractions

Glass and Ceramics, 2022

The effect of admixtures of aluminosilicate cenospheres (ASC) of two fractions on the structure a... more The effect of admixtures of aluminosilicate cenospheres (ASC) of two fractions on the structure and properties of ceramic with waste from the production of mineral wool (MW) was investigated. The influence of different amounts (from 10 to 30%) and different fractions (0.125 – 0.250 mm) and < 0.125 mm ASC on the physical and mechanical properties of ceramic samples after firing at 1000 – 1080°C was determined. It was found that a strong lightweight ceramic with low shrinkage and high porosity can be obtained by using MW as a leaner additive in combination with ASC of two different fractions.

Research paper thumbnail of The influence of calcium nitrate on setting and hardening rate of Portland cement concrete at different temperatures

IOP Conference Series: Materials Science and Engineering, 2017

Calcium nitrate in mortars and concrete is used as a multifunctional additive: as set accelerator... more Calcium nitrate in mortars and concrete is used as a multifunctional additive: as set accelerator, plasticizer, long term strength enhancer and as antifreeze admixture. Used binding material and the amount of calcium nitrate, affect the characteristics of the concrete mixture and strength of hardened concrete. The setting time of the initial and the final binding at different temperatures of hardening (+ 20 °C and + 5 °C) of the pastes made of different cements (Portland cement CEM I 42.5 R and Portland limestone cement CEM II/A-LL 42.5 R) and various amounts of calcium nitrate from 1 % until 3 % were investigated. The effect of calcium nitrate on technological characteristics of concrete mixture (the consistency of the mixture, the density, and the amount of air in the mixture), on early concrete strength after 2 and 7 days, as well as on standard concrete strength after 28 days at different temperatures (at + 20 °C and + 5 °C) were analysed.

Research paper thumbnail of The impact of expanded polystyrene waste of different fineness on the properties of lightweight composite

IOP Conference Series: Materials Science and Engineering, 2019

Expanded polystyrene (EP) is widely used as a packaging material for many types of goods. However... more Expanded polystyrene (EP) is widely used as a packaging material for many types of goods. However, once the material is used, it is disposed of in landfills, where it can remain intact for the lifetime of several generations. Recycling of disposed EP packaging is of high relevance worldwide. The main objective of this study is to make a more detailed research into the effect of EP aggregate waste of different fineness and shape on physical and mechanical properties of porous lightweight aggregates concrete (PLWAC) with EP waste aggregates. Tests were done with Portland cement, EP waste of different fractions, resulted from crushing (EPR) and cutting (EPU), metakaolin, superplasticizer and air entraining admixture. Six batches of PLWAC specimens were formed with different EPR/EPU ratios, ranging from 0.5 to 3.The change in EPR/EPU ratio in PLWAC leads to structural changes and density reduction from 550 to 410 kg/m3 after drying. When EPR/EPU ratio in the PLWAC is increased to 2, the...

Research paper thumbnail of Influence of Plasticizer Amount on Rheological and Hydration Properties of CEM II Type Portland Cements

IOP Conference Series: Materials Science and Engineering, 2015

Research paper thumbnail of The role of temperature and activator solution molarity on the viscosity and hard structure formation of geopolymer pastes

Construction and Building Materials, Feb 1, 2021

Research paper thumbnail of Impact of different types of plasticizing admixtures on the rheological properties and hydration of blended cements

Journal of Thermal Analysis and Calorimetry, Sep 11, 2015

Research paper thumbnail of The synergistic effect of adding a blend of deflocculants and microsilica on the properties of high temperature resistant lightweight concrete with cenospheres

Construction and Building Materials, 2020

Research paper thumbnail of Impact of municipal solid waste incineration bottom ash on the properties and frost resistance of clay bricks

Journal of Material Cycles and Waste Management, Oct 27, 2021

This paper presents an experimental study on the properties, structure and durability (frost resi... more This paper presents an experimental study on the properties, structure and durability (frost resistance: one-side and all-sides freezing and thawing method) of fired clay bricks containing clay and municipal solid waste incineration (MSWI) bottom ash (BA). BA is a non-hazardous substance containing mainly CaO and SiO 2 , and also a low content of heavy metals. Clay was replaced with the BA up to 15% by weight. The bricks were fired at 1000 °C temperature and maintained at the maximum heat for 1 h. According to the research data, BA addition has an effect on the structure and properties of clay bricks. Higher content of BA in the mix of clay bricks leads to the increase of water absorption and total porosity and the decrease of density, and, therefore, lowers the durability (frost resistance) of clay bricks. In clay bricks with higher BA content the typical brick surface damages start appearing after the lower number of freezing and thawing cycles (both in one-side and all-sides freezing and thawing method). Nevertheless, all samples tested for resistance to freezing and thawing in one-side method is classified as F2 class according to the LST EN 772-22:2019 standard (severe weather resistance).

Research paper thumbnail of The synergetic interaction of chemical admixtures on the properties of eco-friendly lightweight concrete from industrial technogenic waste

Construction and Building Materials, Sep 1, 2020

Research paper thumbnail of The Lightweight Porous Fine Aggregate Composite Based on Secondary Raw Materials

Key Engineering Materials, Apr 1, 2019

The main objective of this study was to carry out more detailed research on the effects of the am... more The main objective of this study was to carry out more detailed research on the effects of the amount of cement paste on the physical and mechanical properties of porous fine aggregate concrete (PFAC). Fine foamed glass aggregate (prepared of local glass breaks) and crushed expanded polystyrene aggregate (prepared of local packing tare of household equipment), ordinary Portland cement (OPC), plasticizing and air entraining admixtures, as well as pozzolanic additive – metakaolin-based waste (local waste in production process of foamed glass aggregate), were used for the preparation of forming mixtures. Fine aggregates were coated by an extremely thin layer of porous cement paste in the samples with the lowest amount of OPC (70 kg/m3), and the aggregates contact with each other mainly at the points (empty spaces between the aggregates are interconnected between each other). There were no empty spaces between the aggregates observed, and porous cement paste seems to be monolithic in the samples with the highest amount of OPC (370 kg/m3). Increased amount of OPC (from 70 to 370 kg/m3) results in denser structure, increased dry density, compressive strength, thermal conductivity coefficient and decreased water absorption of the samples.

Research paper thumbnail of The influence of carbon nanotubes on the properties of water solutions and fresh cement pastes

IOP Conference Series: Materials Science and Engineering, 2017

Research paper thumbnail of The Effect of Silica Fume Addition on the Resistance of Concrete to Alkali Silica Reaction

IOP conference series, Nov 1, 2019

Research paper thumbnail of Selection of superplasticisers for improving the rheological and mechanical properties of cement paste with CNTs

Construction and Building Materials, Aug 1, 2020

h i g h l i g h t s Electrical conductivity (EC) of SP influences cement paste temperature and vi... more h i g h l i g h t s Electrical conductivity (EC) of SP influences cement paste temperature and viscosity. EC of different type of SP affects the hydration process of cement paste with CNTs. SP type influences hydration products amount in cement paste with CNTs.

Research paper thumbnail of Experimental study of the behaviour of cement pastes in the presence of carbon nanotubes

Modern building materials, structures and techniques, Dec 3, 2019

Research paper thumbnail of The workability kinetics of phosphogypsum binder

Modern building materials, structures and techniques, Dec 3, 2019

The dihydrate phosphogypsum (PG) based binder workability kinetics were investigated regarding to... more The dihydrate phosphogypsum (PG) based binder workability kinetics were investigated regarding to waterbinder ratio (W/B) and chemical admixtures added to the composition of PG paste. PG was dried at 60 °C and homogenized to powder like particles with collision milling in disintegrator and calcium sulphate hemihydrate was obtained by heating PG at 180 °C. The obtained binder chemical, mineralogical and technological properties were tested and compared to commercial gypsum plaster. Early age (2 h) and 14 d compression strength was determined. The workability and setting time of both-PG and commercial gypsum was investigated with viscosimeter, ultrasonic pulse velocity and Vicat apparatus and correlation between testing methods was obtained. Results indicate that binder based on PG has slightly lower pH (pH 6.3) than commercial binder (pH 6.8) and finer particle size grading leading to increased W/B ratio and more rapid initial setting time. The set retarder could efficiently increase the setting time of PG binder giving extra workability time which is positive factor for prolonged treatment of binder slurry, i.e. to prepare porous gypsum binder. Such approach would give a safer alternative to PG disposal, closing the materials loop and enhancing the circularity of this material.

Research paper thumbnail of The effect of multi-walled carbon nanotubes on the rheological properties and hydration process of cement pastes

Construction and Building Materials, Nov 1, 2018

Research paper thumbnail of Influence of alkaline activator solution ratio on the properties of biomass fly ash-based alkali-activated materials

Journal of physics, 2023

This study explored the use of untreated high-carbon biomass fly ash (BFA) and less alkaline Na2C... more This study explored the use of untreated high-carbon biomass fly ash (BFA) and less alkaline Na2CO3 as an activator to create alkali-activated materials (AAM). This article investigated how the Na2CO3/Na2SiO3 (SC/SS) ratio of the alkaline activator solution (AAS) influenced the setting time, structural development and physical-mechanical properties of BFA-based AAM pastes that were cured at room temperature. With an increase in the SC/SS ratio, AAM pastes’ initial and final setting times shorten, respectively. The AAM sample with the lowest density and ultrasonic pulse velocity (UPV) value also has the maximum water absorption. The compressive strength of AAM samples dropped after 7 days of curing while the SC/SS ratio increased. Nevertheless, after 28 days of curing, the compressive strength of AAM samples rose with a rising SC/SS ratio. The results for density, water absorption, and UPV were corroborated by the scanning electron microscope (SEM) analyses, which demonstrated that when the SC/SS ratio rises, the structure of the samples gets denser and more homogeneous, in line with the increased compressive strength of the samples.

Research paper thumbnail of Flexural Behavior of Reinforced Concrete Beams Strengthened by Textile Reinforced Magnesium Potassium Phosphate Cement Mortar

Frontiers in Materials, Aug 21, 2020

Research paper thumbnail of Moisture-mechanical performance improvement of thermal insulating polyurethane using paper production waste particles grafted with different coupling agents

Construction and Building Materials, May 1, 2019

h i g h l i g h t s Titanate coupling agents reduce particle-polyol mixture viscosity more than 2... more h i g h l i g h t s Titanate coupling agents reduce particle-polyol mixture viscosity more than 2 times. Titanate coupling agents form hydrophobic monomolecular layer on the particle surface. Coupled paper waste particles increase compressive and tensile strengths. Coupled paper waste particles initiate nucleation process in particle-polyol mixture.

Research paper thumbnail of A Study of Rapeseed Oil-Based Polyol Substitution with Bio-based Products to Obtain Dimensionally and Structurally Stable Rigid Polyurethane Foam

Journal of Polymers and The Environment, Jun 9, 2018

Water-blown polyurethane foams from low functionality polyols are characterized by intensive shri... more Water-blown polyurethane foams from low functionality polyols are characterized by intensive shrinkage, high density, post blowing, and longer demold time. These drawbacks can be partially, or fully, eliminated by varying chemical parameters of the main components. Therefore, an aliphatic polyester rapeseed oil-based polyol was modified with bio-based glycerin (RGL) and propylene glycol (RPG). The impact of the molecular weight and hydroxyl value of the blends were evaluated by testing obtained bio-based polyurethane foams. Compared to RGL-based foams, RPG-modified foams had the strictest standard (EN 13165) requirements regarding dimensional stability. These foams demonstrated a reduced apparent density from 12.6 to 20.8%, a faster foam curing capability by 47%, and the shortest demold time due to the open cell structure. The RGL modified foams had better cross-linking capability, slower ageing of thermal conductivity, and an increased compressive strength of 82.7% compared to the non-modified foam.