Permeable Voids Research Articles

Effect of Sonicated Deionized Water on The Early Age Behavior of Portland Cement-Based Concrete and Paste

The quality and performance of concrete is improved by the introduction of multi-walled nanotubes (MWCNTs). However, some research has shown negligible improvement. This paper investigates the effect of sonicated water and sonicated water plus MWCNTs on the properties of Portland cement concrete and paste. Changes are expected in the areas of compressive strength, load versus displacement, absorption, void space (ASTM C642) ratio, and microstructure. Deionized water (DI), sonicated deionized water (SDI), and sonicated deionized water with 0.01% MWCNTs concentration (SDI + MWCNTs) were used in preparing three batches. Compressive strength was improved by 18% for samples made with SDI and 21% SDI + MWCNTs in comparison with samples made with DI water. The load versus displacement, absorption, and permeable void ratio were improved for SDI and SDI + MWCNT samples. Results revealed the main effects are related to the sonication of water rather than incorporation of untreated MWCNTs. The scanning electron microscopy observations showed that cement paste samples made with SDI and SDI + MWCNT water have the same distinctive microstructure with more ettringite needles than paste samples made with deionized water. The hypothesis explaining those effects is that the sonication process produces a salt-calcium peroxide (CaO2), which enhances the early mechanical and microstructural properties of Portland cement.

An investigation of key mechanical and durability properties of coconut shell concrete with partial replacement of fly ash

AbstractThis study investigated the effect of adding fly ash on the mechanical and durability characteristics of coconut shell (CS) concrete. Two different mixes were developed, one with CS and the other with conventional aggregate and CS as coarse aggregate. Cement was replaced with Class F fly ash in terms of weight at 0, 10, 20, and 30% in both mixes. Test result showed that the CS concrete with 10% fly ash replacement level exhibited the highest compressive and tensile strength. The addition of fly ash decreased the porosity of CS concrete due to its fineness and increased hydration products in the matrix at later ages. Additionally, it also improved the weak aggregate interfacial transition zone of CS lightweight concrete. Thus, the fly ash addition in CS concrete showed lower values of water absorption, permeable voids, sorptivity, and chloride permeability. Furthermore, the increasing content of fly ash addition improved the durability characteristics of CS concrete considerably.

Modification of geopolymer with size controlled TiO2 nanoparticle for enhanced durability and catalytic dye degradation under UV light

Geopolymer- a silica alumina-based polymer has attracted generous amount of interest since the last decades as a promising alternative binder to ordinary Portland cement (OPC) in the construction sector. Proper utilization of industrial waste (Fly ash) and their functionality enhancement is explored in the present exertion by incorporating titanium oxide (TiO2) nanoparticle with different size in it. Along with the development of advanced building composite photocatalytic ability of the synthesized product was also assessed. Rutile phase TiO2 NPs were synthesized hydrothermally and annealed at different temperatures which result in differences in their overall size. Different materials characterization techniques have been carried out for confirmation of phase, functional bond, binding energy, and morphology respectively. Geopolymeric (GT) composites (GT30, GT50, and GT100) were prepared at ambient temperature using this size-variant TiO2 NPs in fly ash and alkali activator. Integration of TiO2 nanoparticles (5%) enhances mechanical properties where the optimized composite GT30 shows the maximum compressive (53.59 MPa) and tensile strength (6.8 MPa). Mercury Intrusion porosimetry (MIP) and atomic force microscope (AFM) studies indicate that TiO2 nanoparticles of 30 nm (T30 NPs) reduce porosity and roughness of the structure, thus lead to densified matrix and high durability performances. Additionally, GT30 mortar has low water absorption capacity as T30 NPs decrease the apparent volume of permeable voids in its matrix. Degradation of Methylene Blue (MB), a model contaminant was investigated under ultraviolet (UV) light illumination. T30 NPs (1 mg) and GT30 (5 mg) are found to degrade >95% dye solution within 90 min towing to the high surface area of TiO2 NPs and free radical generation. Such outcomes are well fitted in the Langmuir–Hinshelwood first-order rate model. These results will pave the way to explore industrial waste; fly ash in geopolymer for the excellent durability and wastewater treatment through dye degradation under UV light illumination with the aid of TiO2 NPs.

Lightweight aggregate concrete produced with crushed stone sand as fine aggregate

Lightweight aggregate concrete mixtures incorporating 0, 10, 20, and 30 weight percent replacement of normal-weight aggregate with lightweight aggregate and crushed stone as fine aggregate were tested at 7, 28, 56, and 90 days for various strength and durability characteristics of hardened concrete. Test results indicated that compressive, flexural, and split tensile strengths and static modulus of elasticity of concrete mixtures reduced with an increase in the percent replacement of normal-weight aggregate with lightweight aggregate. Furthermore, the volume of permeable voids and hence moisture sorption in lightweight aggregate concrete reduced as the lightweight aggregate content was increased pointing at the enhanced durability of the lightweight aggregate concrete mixtures. A significant reduction in dry density of hardened concrete was recorded due to the inclusion of lightweight aggregate in concrete mixtures. Considering the strength and reduction in dry mass, 20 wt.% replacement of normal-weight aggregate with lightweight aggregate is considered to be an optimum level. Reduced density of lightweight aggregate concrete mixtures is viewed as a major source of economical design of structural members as the lower concrete density will result into a reduction of self-weight of the structural members, which will allow the economical structural design of such members with smaller cross-sections. Test results of this work also showed the viability of 100% replacement of desert sand with crushed stone sand as fine aggregate towards the production of lightweight aggregate concrete.

The Effectiveness of Palm Oil Fuel Ash Cement Paste to Control Degradation in Ammonium Nitrate Solution

This paper presents the use of treated palm oil fuel ash (POFA) as a pozzolanic material in modified cement paste to control degradation in ammonium nitrate environment. The POFA used in this study had a mean diameter of 8.7µm. The treated POFA was used to replace cement in different percentage of 0%, 10%, 20% and 30% with a constant water to cement ratio of 0.4. 50mm cement cubes was prepared for mechanical, durability and micro-structural test. Mechanical test consisted of the compression strength test and durability test consisted of the Volume of Permeable Voids Test (VPV). Meanwhile, micro-structural test consisted of the Thermo-gravimetric analysis (TGA). After 28 days of full water curing, the 50mm cubes samples were immersed in 20% ammonium nitrate solution until 90 days. Based on the test results, it was observed that, cement cubes replaced with 20% POFA had good resistance against ammonium nitrate solution. However, in order to improve the current study, a number of recommendations had been suggested.

A study on the influence of steel fibers on the performance of Fine Reclaimed Asphalt Pavement (FRAP) in pavement quality concrete

With natural resources becoming scarce day by day, there is a need to find sustainable alternatives to raw materials for concrete. In the current study, use of Fine Reclaimed Asphalt Pavement (FRAP) as a substitute to natural fine aggregates (NFA) and effect of crimped steel fibers on the strength and durability of concrete is being studied. RAP, removed old flexible pavement containing asphalt and aggregates, if processed correctly, can be a good source for fine and coarse aggregates. The variables of study included FRAP content (0–100%) and steel fiber content (0% and 1%). For all replacements of NFA with FRAP, a systematic reduction in hardened properties was observed. Even though the compressive strength of concrete increased marginally by adding fibers, the tensile characteristics of concrete improved by about 40–50%. The water absorption, volume of permeable voids, and sorptivity were used as measures of durability characteristics of the concrete, increased with FRAP content increased and decreased with addition of fibers. These results suggest that if appropriately designed, up to 50% of FRAP can be used as a partial replacement to NFA.

Characterization of RCAs and their concrete using simple test methods

From a sustainability point of view, the use of recycled concrete aggregate (RCA) in concretes is of great interest in the present day. The original virgin concrete from which RCA is obtained determines the properties of the RCA, and it also controls the durability of recycled aggregate concretes (RACs) produced. In this study, the performance of three sources of RCAs with different absorption, obtained from crushed concrete pavement and stockpiles, were evaluated using various mechanical, thermal and non-destructive durability test methods. Suitability of RCA for cold climates was evaluated using a test method for the resistance of unconfined coarse aggregate to freezing and thawing (CSA A23.2-24A). The mechanical properties of the RACs were assessed with the compressive strength test. Non-destructive durability tests on the RACs included surface and bulk electrical resistivity, ultrasonic pulse velocity (UPV), and volume of permeable voids (ASTM C642, boil test). The effect of RCAs on the thermal conductivity of concrete was also evaluated. All of the measured properties of RACs were compared with a concrete mix containing natural virgin aggregate. Correlations between the absorption of aggregates and measured properties were also established. The test results provide an overall understanding of the feasibility of using different sourced RCAs in concretes.

Utilization of Fly Ash Cenosphere for Production of Sustainable Lightweight Concrete

This investigation is intended to develop lightweight concrete by replacing the natural fine aggregate (NFA) with an industrial waste called fly ash cenosphere (FAC). For achieving this target, eleven concrete mixes were prepared which include one control mix and another ten mixes prepared in two phases by replacing 20%, 40%, 60%, 80% and 100% of NFA with FAC. In the first phase, additional water required for saturating the FAC was added to the concrete mix to maintain a constant slump (80 ± 5 mm), but in the second phase of investigation, super-plasticizer was used to maintain the same slump. The properties of concrete, such as workability, fresh density, hardened density, compressive, flexural and split tensile strength, rebound number, water absorption and volume of permeable voids were studied. From the above study, it is found that the density of concrete decreases with the increase in FAC content and satisfies the requirement of lightweight concrete if 100% NFA is replaced by FAC. On the other hand, the strength of concrete decreases with the increase in FAC content of concrete. However, the addition of super-plasticizer showed a remarkable enhancement in the hardened properties of concrete for all the mixes, but at the cost of the marginal increase in density of concrete. The mix with 80% FAC and super-plasticizer is found to be optimum one, which can be considered as the sustainable lightweight structural concrete of M25 grade, i.e. the desired grade, utilizing high volume of wastes (FAC) and preserving equal amount of natural resources (NFA).

Durability properties evaluation of self-compacting concrete prepared with waste fine and coarse recycled concrete aggregates

Using recycled aggregates obtained from construction and demolition waste in concrete is a promising and appropriate solution to control the excessive consumption of natural resources in construction. In this study, the effect of fine and coarse recycled concrete aggregates (RCA) was evaluated by replacing 25%, 50%, 75% and 100% in self-compacting concretes (SCC) on mechanical properties such as compressive and tensile strength, ultrasonic pulse velocity in hardened concrete and durability properties including water absorption, volume of permeable voids, electrical resistivity and resistance to chloride ion penetration. The fresh properties of the SCC were determined using slump flow and J-ring tests. Three series of mixes were made; in the first series, coarse recycled aggregates were replaced by natural coarse aggregates. In the second series, fine recycled aggregates replaced fine natural ones. In the third series, the combination of the coarse and fine recycled aggregates was used in the mixes. In all mixes, the cement content and water-cement ratio were constant equal to 420 kg/m3 and 0.4, respectively. Replacement of recycled aggregates causes a decrease in compressive strength of all mixes and their effect on tensile strength was insignificant. The measured durability properties such as water absorption and volume of permeable voids of recycled aggregate concretes were also adversely affected by the incorporation of RCAs and these properties increase with an increase in RCAs contents. The results indicate that replacement of 25% coarse RCAs had no significant effect on the durability properties of self-compacting concrete including electrical resistivity and chloride ion resistance, while with the increasing fine and coarse RCAs the electrical resistivity and resistance to chloride ion penetration decreased. Results indicate that the resistance to chloride ion penetration was greatly reduced by increasing replacement of fine recycled aggregates. Very strong correlations of electrical resistivity with water absorption, and total charge passed with permeable voids of mixes containing RCA were also observed.

Recycled geopolymer aggregates as coarse aggregates for Portland cement concrete and geopolymer concrete: Effects on mechanical properties

The available literature on recycling of geopolymer concrete is currently limited to application of recycled geopolymer aggregates as coarse aggregates for new geopolymer concrete. This paper highlights an alternative waste management strategy for geopolymer concrete construction and demolition waste by illustrating the suitability of recycled geopolymer aggregates for full or partial replacement of coarse natural aggregates in the widely used Portland cement concrete. The properties of Portland cement concrete and geopolymer concrete made with varying contents of coarse geopolymer recycled aggregates (0%, 20%, 50% and 100% coarse natural aggregates replacement) are investigated and compared with those of Portland cement concrete containing recycled Portland cement concrete aggregates. The results indicate that up to 20% replacement of coarse natural aggregates with recycled geopolymer concrete aggregates results in only insignificant reductions in the modulus of elasticity, flexural strength and volume of permeable voids as well as a moderate reduction in compressive strength of Portland cement concrete. The negative effects of varying amounts of recycled geopolymer concrete aggregates on the properties of Portland cement concrete is however found to be slightly more significant than those caused by same proportions of recycled aggregates produced from Portland cement concrete waste. Furthermore, incorporation of coarse recycled geopolymer concrete aggregates is found to lead to more significant negative effects on properties of Portland cement concrete than geopolymer concrete. These include respectively 21%, 8.3% and 3.4% further reductions in compressive strength, modulus of elasticity and flexural strength of RAGC compared to RAG at 100% coarse aggregate replacement ratio, highlighting a higher compatibility between geopolymer recycled aggregates and geopolymer binder than Portland cement binder.

Durability studies on ferrochrome slag as coarse aggregate in sustainable alkali activated slag/fly ash based concretes

Utilization of industrial byproducts in concrete reduces carbon footprint, associated with production of ordinary Portland cement (OPC), and also indirectly controls rapid depletion of natural resources in the form of natural coarse aggregate (NCA). This study reports the durability effect of alkali activated slag/fly ash concretes (AASFC) with ferrochrome slag (FCS) as coarse aggregate. Different AASFC mixtures were prepared with two control factors i.e., fly ash (FA) content (0, 25, and 50% by weight as a replacement to Ground granulated blast furnace slag (GGBS)), and FCS content (0, 50, and 100% by volume as a replacement to NCA). Total nine mixtures were examined for three different durability tests i.e., volume of permeable voids (VPV), acid resistant test, and sulphate resistant test. Further, embodied energy (EE), and Embodied carbon dioxide emission (ECO2e) were also utilized to optimize the AASFC mixtures by grey relational analysis (GRA). Analysis of variance (ANOVA) is used as a statistical tool to investigate the effect of FA, and FCS content on the overall durability and ecological performance of AASFC mixtures. Results show that, addition of FA increases the durability performance (in % age), and addition of FCS decreases the durability performance (in % age) in AASFC mixtures. AASFC mixture with composition of 50% GGBS, 50% FA, and 100% FCS is considered as most suitable mixture.

Nitrite admixed concrete for wastewater structures: Mechanical properties, leaching behavior and biofilm development

This study systematically investigated the impacts of calcium nitrite addition on the mechanical properties and biofilm communities of concrete-based wastewater infrastructures using sulfate resistant cement through standard tests and DNA sequencing, respectively. The results revealed that setting time and water demand for normal consistency were reduced, but slump, drying shrinkage, and apparent volume of permeable voids increased with calcium nitrite dosage up to 4% weight of cement. The cumulative leached fraction of nitrite, 28-day compressive strength and biofilm communities were not significantly affected by calcium nitrite dosages. The addition of calcium nitrite into concrete is environmentally friendly to wastewater infrastructures.

Effects of Coconut Sawdust on Mechanical Properties and Porosity of Concrete Mixtures

The presence of coconut sawdust in North Sulawesi is very potential to be utilized as an alternative material for application in construction field. This paper aims to investigate experimentally the effect of coconut sawdust as an addition on concrete mixtures based on compressive strength, flexural strength and volume permeable voids tests. In this study, coconut sawdust with percentage of 2.5%, 5% and 7.5% by weight of cement was added into concrete mixture. The results show that concrete containing 5% of coconut sawdust exhibited highest compressive strength at 7 days with average value is 25.71 MPa while at 28 days the compressive strength is 30.50 MPa and there is no significant difference compared with 2.5% variation. When comparing the results of flexural strength test between 5% and normal cement concrete, the highest result is achieved by normal concrete reaching the value 6.78 MPa while for the concrete with 5% of coconut sawdust addition is only on 4.82 MPa. In terms of the volume of permeable voids, the results show that the porosity of concrete with coconut sawdust increased with the increase of percentage of coconut sawdust at 7 days but the values decreased as the age of curing increased.

Physical-mechanical properties of fly ash/GGBFS geopolymer composites with recycled aggregates

The properties of fly ash and ground granulated blast furnace slag (GGBFS) combination based geopolymer composites containing recycled aggregate are investigated in this study, which obtained from construction and demolition wastes. The effects of recycled aggregate replacement and GGBFS inclusion on the physical and mechanical properties of geopolymer composites were investigated in this study. The scanning electron microscopic (SEM) were conducted to provide a thorough insight into the characterization of microstructures. The results reveal that using recycled aggregate has an insignificant impact on workability and setting time, while it causes a reduction in physical and mechanical properties. The inclusion of GGBFS reduces workability and setting time. However, improved physical and mechanical properties can be achieved in the geopolymer composites after the incorporation of GGBFS, and this effect is more prominent in the geopolymer composites containing recycled aggregates. The water absorption and sorptivity exhibit a strong correlation with the volume of permeable voids of geopolymer composites. Besides, very good relationships were established between the compressive strength and other mechanical properties, and these relationships fitted reasonably well with the other predictions.

Eco-efficient low binder high-performance self-compacting concretes

The use of high-performance concrete (HPC) is widespread as an eco-efficient building solution because it provides greater durability and, hence, a longer lifetime than conventional concrete, reducing the need for repairs and demolitions. In addition, HPCs require lower binder contents per unit of compressive strength. However, self-compacting HPCs (HPSCCs) generally require high binder contents to ensure the fresh state stability of the concretes, which could hinder the ecological advantage. Thus, this work aimed to produce HPSCCs with low binder contents. A mix design method was proposed to optimise the material proportions. A fine fly ash was used to replace Portland cement from 0 to 30%. The rheological properties of the SCCs were evaluated by the workability tests slump flow, T500, V-funnel, L-box and VSI. Compressive strength, resistance to chloride ion penetration, volume of permeable voids and capillary water absorption were determined at 28 and 91 days. Finally, the CO2 intensity (kg CO2/m3·MPa) of the mixtures produced was estimated and compared to those of HPSCCs reported in the literature. The mix design method allowed for the production of SCCs with 365 kg of binder/m3 of concrete, with slump flow of 700 ± 25 mm and stable in the fresh state (VSI of 0 or 1). The fly ash-containing concretes showed compressive strengths up to 59 MPa at 28 days (10% fly ash) and 71 MPa at 91 days (20 and 30% fly ash), with good indicators of durability: down to 403 Coulombs for RCPT and up to 41.8 kΩ·cm for surface electrical resistivity. The CO2 intensity of the concretes produced are among the lowest reported in the literature for HPSCCs (down to 4.7), together with the lowest binder content reported for this type of concrete (365 kg/m3 of concrete).

Mechanical and microstructural properties of metakaolin geopolymer

Fly ash (FA) is a commonly used aluminosilicate raw material for the synthesis of geopolymers (GPs). Metakaolin (MK) is also an aluminosilicate-rich material that is relatively pure and has a huge potential as a GP precursor. In this research, FA is replaced by MK at quantities of 0, 25, 50 and 75% by mass (MK0, MK25, MK50 and MK75, respectively). The silicon (Si)/aluminium (Al) ratio of the MK precursor is significant in strength development. For a silicon/aluminium ratio equal to 0·86 (M1), the compressive strength of GP concrete (GPC) decreased by 57% for MK75 at 120 d. For a silicon/aluminium ratio of 1·11 (M2) of the MK75 mix, the compressive strength is almost same as that of MK0 at 120 d, and for a silicon/aluminium ratio of 1·21 (M3), the compressive strength increases by 16% for MK75 at 120 d. Nevertheless, the volume of permeable voids (VPV) percentage is reduced to 0·638 for MK75 (M3) compared to 18·58 for MK0. Scanning electron microscopy images of hardened MK-modified GPC support the results showing reduced VPV compared to that of FA-GPC. Energy-dispersive X-ray spectroscopy analysis of the hardened MK50 mix of M3 GPC confirms the presence of Si–O–Si bonds, resulting in higher strength.

Evaluation of Characteristics of Concrete Mixed with Bamboo Leaf Ash

Background: Concrete production around the globe is in billions of tons. Consequently, million metric tons of carbon dioxide are produced annually due to the cement consumption and production which, in turn, cause environmental menace. Objective: This research work examines the use of Bamboo Leaf Ash (BLA) as supplementary cementitious materials. Methods: The physical, mechanical, and durability properties were studied by partial substitution of cement with BLA at 0, 5, 10, 15, and 20% sequentially. Concrete cubes were cast and cured at 7, 28, 56, and 90 days. Beams were cast and cured at 28 days. A total number of five mixes were investigated, four out of the mix were dedicated to examining the impacts of BLA on the characteristics of concrete. Results: Soundness, consistency, initial and final setting time of cement paste values were lower than bamboo blended paste values at 5%, 10%, 15%, and 20% percentage replacement, respectively. The split tensile, compressive, and flexural strength values of conventional concrete were lower than bamboo leaf ash concrete accordingly. Water absorption, permeable voids, sorptivity, and bulk dry density of conventional concrete were higher than bamboo leaf ash concrete at all level of replacements. Conclusion: According to the analysis and experimental results obtained, BLA improved split tensile, compressive, and flexural strength benchmark at 10% as the optimum level of replacement. BLA reduced setting time, consistency, compacting factor, slump, water absorption, permeable voids, sorptivity, and density. To this end, BLA can be considered as a good pozzolanic material which can save the cost of construction, and improved concrete properties.

Evaluating the physical and strength properties of fibre reinforced magnesium phosphate cement mortar considering mass loss

Fibre reinforced magnesium phosphate cement (FRMPC) composites are drawing attention day by day in the practical applications due to their excellent strength performance. Keeping this issue in mind, this study aimed to add a little contribution on this area by examining the physical and strength properties of FRMPC mortars containing micro-steel fibre (MSF), polyvinyl alcohol fibre (PVA) and basalt fibre (BF). Each fibre content with consecutive four dosages such as 0.6%, 0.8%, 1% and 1.2% of the total quantity of binders and aggregate, were added in the designated combinations. The analyzed results exhibited that porosity, pore degree of saturation, reduction of permeable voids, density and water absorption properties were well improved for adding 0.6% and 0.8% MSF and PVA, and 0.6% BF fibres in the matrices, whereas the rest two selected higher fibre contents made the microstructure of MPC specimens sponginess by forming the substantial quantity of internal pores. Mass loss was recorded about 0.6%−1% for air cured FRMPC samples at 28 d by adopting abrasion test, where the static immersion liquid condition revealed around 1.5% − 3.0%. In addition, air cured samples containing 0.8% MSF showed the highest compressive strength around 54.8 MPa and 82.6 MPa at 1hr and 28 d, respectively than other considered combinations. Moreover, FRMPC syntheses exposed around 10% − 15% strength loss in water environment as compared to air. SEM observations presented the well interfacial closeness of MSF by coating the hydration products that probably enhanced the noteworthy strength quality of MSF-MPC mortars. XRD investigations also corroborated the possible explanation for reducing the strength loss in water regime by presenting the low peaks of struvite minerals, which was happened due to the dissolution of mass that accorded with the experimental results. These findings might show a path for potential use of FRMPC specimens to enhance the durability properties.

Influence of fluidity on mechanical and permeation performances of recycled aggregate mortar

Abstract The use of recycled fine aggregates in making mortar is an effective measure to increase the social and ecological values these days due to the pressing issues associated with the over-exploitation of natural sand as well as disposal of construction and demolition wastes. To counteract the synergetic effects of W/C ratio, recycled fine aggregates quality and its content, fluidity was considered as parameter to formulate the recycled aggregate mortar. The experimental results of this investigation elucidate the effectiveness of fluidity on mechanical and permeation performances of recycled aggregate mortar. A comparison with the outcomes of conventional mortar is also presented. The experimental outcomes reveal that, recycled aggregate mortar requires additional amount of water to attain the same fluidity of controlled mortar due to inferior characteristics of RFA, such as high initial water absorption and volume of voids with in mortar. The setting characteristics of recycled aggregate mortar were influenced by the fluidity, recycled fine aggregates quality and its content and their setting times were earlier than that of controlled mortar. However, recycled aggregate mortar corresponding to the fluidity of 110 ± 2.5 mm and 160 ± 2.5 mm attained lower strength characteristics, lower pulse velocity value, higher permeable void content, higher water absorption by immersion and higher sorptivity than those associated to the fluidity of 135 ± 2.5 mm. Therefore, recycled aggregate mortar associated to the moderate fluidity of 135 ± 2.5 mm is feasible and exhibits better mechanical and permeation performances.

Thermal properties and residual strength after high temperature exposure of cement mortar using ferronickel slag aggregate

This study evaluates the thermal properties of cement mortar using by-product ferronickel slag (FNS) fine aggregate and its residual strength after high temperature exposure. Compressive strength of mortar increased when FNS was used up to 50% replacement of sand and then reduced with further increase of FNS. Volume of permeable voids (VPV) increased by 4% and 7% respectively for using 50% and 100% FNS fine aggregate. Thermal conductivity of mortar decreased from 2.34 W/m.K for using 100% sand to 1.65 W/m.K and 1.16 W/m.K for 50% and 100% FNS, respectively. Similarly, specific heat increased from 2.18 MJ/m3.K to 2.43 MJ/m3.K for 100% replacement of sand by FNS. These changes of VPV and thermal properties are attributed to the cavity of FNS particles, and their larger size and angular shape. Residual strengths of mortar after exposure to 800 °C were found marginally less for using FNS aggregate. This is attributed to the decrease of thermal conductivity of mortar by FNS. Overall, FNS aggregate showed improved thermal insulating properties and thermal mass of mortar without compromising compressive strength. Therefore, FNS can be considered for use as an energy efficient sustainable building material.