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Industrial solid waste has been widely used as an alternative additive for bituminous material modification. This study aims to evaluate the basic properties and quantify the leaching potential of modified asphalt binders incorporating crumb rubber powder (CRP) from waste tires and tin slag (TS) for a local smelting company. Three percentages of CRP and TS, at 5, 10, and 15%, were considered. The conventional asphalt binder (PEN 60/70), CRP, and TS-based modified asphalt binders were analyzed for toxicity, softening point, penetration value, elastic recovery, torsional recovery (TR), and coatability index. The findings indicated that the addition of the waste materials led to no significant heavy metal content in the asphalt binder mix. Moreover, the basic and physical properties of the asphalt binders were also improved by 5, 10, and 15% of the waste, respectively. However, TS waste exhibited limited effects on all the parameters and had a 5% optimum dosage. The modified binders’ results showed that the CRP modified asphalt binders had fewer heavy metals and responded more to elastic recovery and coatability.

Purpose The purpose of this study is to know the influence of palm oil fuel ash and metakaolin on the strength of concrete and crack resistance of reinforced concrete beam. An ordinary portland cement has been used in the concretes production where it is an important material to be considered due to its nature that reacts with every substance present. During the cement production, a significant amount of carbon dioxide is emitted from the clinker in rotary kiln and lot of energy is required in the production processes. Such an event can be prevented by replacing the part of cement with metakaolin (MK) and palm oil fuel ash (POFA). Aside from being a cementitious alternative, the materials can also contribute to a greener environment and more sustainable building, as POFA is available in Malaysia and may be used to substitute cement and minimize pollution. Design/methodology/approach This study assesses the effect of MK and POFA on the concrete in terms of compressive strength and cracks pattern of the reinforced concrete beam based on the relevant previous studies. Findings From this study, the compressive strength of concrete containing MK and POFA was higher than the control mix with the percentage of improvement in the range of 0.8%–78.2% for MK and 0.5%–14%, respectively. The optimum content of MK and POFA is between the range of 10% and 15% and 10% and 20%, respectively, to achieve high strength of concrete. Other than that, the inclusion of MK to the concrete mix improves the strength of reinforced concrete beams and reduces cracks on the surface of reinforced concrete beams, whereas the inclusion of POFA to the concrete mix increases the cracks on reinforced concrete beams. The cracks appeared within the flexure zone of every beam containing the MK and POFA. Originality/value It was found that the fineness of MK and POFA has a significant influence on the mechanical properties of concrete.

As industrial globalisation and waste output continue to grow, solid waste management is one of the most pressing worldwide environmental challenges. Solid wastes include both the heterogeneous mass of urban throwaways and the homogeneous accumulations of agricultural, industrial, and mineral wastes. Clinical waste (CW) has a significant negative influence on both human health and the environment. To dispose hazardous CW, a proper waste management system should be necessary, and incineration should be the best possible option for reducing the volume of this hazardous waste. Incineration is being developed in Malaysia as a means of disposing clinical and hazardous waste. Currently, 170 common CW treatment facilities with 140 incinerators are accessible around the country. The combustion procedure kills pathogens and reduces waste volume and weight, but it leaves a solid residue known as clinical waste ash (CWA), which raises heavy metal, inorganic salt, and organic compound levels in the environment. Because metals are not eliminated during incineration, dumping CWA in a landfill could contaminate groundwater. Leachate is the liquid created when waste decomposes in a landfill and water filters through it. The most common method of disposing of CW ashes is to transfer them to a landfill. Landfills should install a top cover after closure for hazardous waste landfills. Due to a lack of space and the high expense of land disposal, recycling technologies and the reuse of ash in various systems have developed. Clinical waste incineration fly ash (CWIFA), a solid waste substance from CW incineration, typically includes mobile heavy metals and can cause significant pollution when reused. The standard requirement for removing CWIFA in dumpsites should be below the metal limit stated by the U.S. Environmental Protection Agency (USEPA). Much recent research on the usage of CWIFA has concentrated on mitigating their effects on the environment. Several studies have confirmed the utilisation of CWIFA in the construction field and agriculture to reduce the leaching of its hazardous components into the environment. Compressive strength decreased with the percentage amount of CWIFA due to the substitution of cement with CWIFA. CWIFA mix with 20% cement is the broad-scale application of CWIFA for geotechnical constructions. Heavy metals (Cd, Cu, Ni, Pb, and Zn) are strongly immobilised by the cementitious matrix. Solidification/stabilisation (S/S) materials can be dumped in landfills with less environmental protection than untreated waste. When utilising a CWIFA in mortar, the primary environmental concern is if any harmful materials leach out during the initial curing process or throughout the life of the mortar. Toxicity characteristic of leaching procedure (TCLP) analysis of all CWIFA specimens found amounts of heavy metals below regulatory limits. Solidification of waste with cement and solidified waste has become a popular way of minimising the atmosphere's emissions. The amount of CWIFA generated is expected to increase nationally and globally. There is an immediate need for further evaluation of ash leachate investigations for proper disposal and usage of ash in construction materials.

The paper reports the outcome of the research work on mechanical and microstructural changes to palm oil fuel ash engineered alkali-activated cementitious composite (POFA-EACC) mortar exposed to di...

This research was carried out to study the behaviour of concrete, specifically flexural strength, by incorporating two types of pine needle leaves (green, and brown) recycled as fibre reinforcement in the concrete. The other goal of the study is to compare the two types of fibre and determine the maximum proportion of fibre to be added in the normal concrete. OPC concrete with 0%, 1% and 2% pine needle leaves fibre (green, and brown) was prepared based on the total weight of the mixture. At an ambient temperature of 28 ± 2°C, the specimens were checked for flexural strength (FS). Laboratory test results based on short term investigation reveals that the flexural strength of concrete containing brown pine fibre (BPF) is higher than that of Green pine fibre (GPF), and also higher than normal (OPC) concrete. The optimum proportion of pine needle leaf fibre is the brown fibre (fallen leaves) to be added in the concrete as fibre is 1% by the total weight of the mixture, which gave a positive reaction from the test that was performed.

The strength, pore structure, morphology and mineralogical composition of hydration products of natural pozzolan (NP) and nanosilica (nSiO2) based alkali activated binder (AAB) were examined. It wa...

The use of reinforced concrete flat slabs in building construction increases the floor-to-floor clearance, expedites site operations, and offers aesthetically rewarding features. However, punching shear failure in a flat slab is brittle in nature and can be potentially catastrophic. Many studies have been conducted to improve the punching shear capacity of flat slabs but some of the proposed punching shear reinforcements were complicated and costly. This research aimed to evaluate the effectiveness of a simple and cost-effective; truss-shaped punching shear reinforcement embedded in a 1200 mm × 1200 mm × 175 mm thick flat slab specimen. Three types of truss-shaped punching shear reinforcements were prepared. All specimens were supported at the edges and subjected to gravity load tests. The results showed that the introduction of truss-shaped punching shear reinforcement increased the punching shear capacity in the range of 7.71% to 21.47%. The maximum deflection of these specimens exhibited an insignificant increase compared to the control specimen, suggesting that punching failure governed the ultimate behavior. The additional strength offered by truss-shaped punching shear reinforcement makes flat slabs as a construction material more appealing because they allow them to withstand higher design loads.

Since diminishing the consumption of cement has many benefits, ongoing research on the incorporation of the industrial/agricultural wastes as an alternative or partial substitution for cement is of paramount significance. This study aims to examine the effect of steam curing regimes (SCRs) on the chloride resistance and microstructure of high-strength green concrete (HSGC). To this end, palm oil fuel ash, a type of waste from the palm oil industry, was treated so that ultrafine palm oil fuel ash (U-POFA) could be obtained. U-POFA was utilized as a partial substitute of the mass of cement at 0%, 20%, 40%, and 60% to produce HSGC. Varying steam curing temperatures (50 °C, 65 °C, and 80 °C) and varying periods (6, 11, and 16 h) were applied to the HSGC. Moreover, a steam curing cycle that did not exceed 24 h was applied. The tests performed on the HSGC samples included compressive strength (CS), rapid chloride permeability, and rapid chloride migration. The evaluation of the microstructure of the HSGC samples was undertaken via Mercury Intrusion Porosimetry (MIP) in addition to scanning electron microscopy with energy dispersive x-ray. The results showed that the application of SCRs with a high volume with UPOFA resulted in enhanced CS, chloride resistance, and microstructure properties of HSGC at an early age of 3 days and a later age of 360 days. Such enhancement in the concrete properties mainly depends on the cement replacement rates by U-POFA, temperature, and the steam curing period. It was, therefore, concluded that U-POFA played a key role in reducing the negative impact, which might have been caused by the utilization of varying SCRs. Since diminishing the consumption of cement has many benefits, ongoing research on the incorporation of the industrial/agricultural wastes as an alternative or partial substitution for cement is of paramount significance. This study aims to examine the effect of steam curing regimes (SCRs) on the chloride resistance and microstructure of high-strength green concrete (HSGC). To this end, palm oil fuel ash, a type of waste from the palm oil industry, was treated so that ultrafine palm oil fuel ash (U-POFA) could be obtained. U-POFA was utilized as a partial substitute of the mass of cement at 0%, 20%, 40%, and 60% to produce HSGC. Varying steam curing temperatures (50 °C, 65 °C, and 80 °C) and varying periods (6, 11, and 16 h) were applied to the HSGC. Moreover, a steam curing cycle that did not exceed 24 h was applied. The tests performed on the HSGC samples included compressive strength (CS), rapid chloride permeability, and rapid chloride migration. The evaluation of the microstructure of the HSGC samples was undertaken via Mercury Intrusion Porosimetry (MIP) in addition to scanning electron microscopy with energy dispersive x-ray. The results showed that the application of SCRs with a high volume with UPOFA resulted in enhanced CS, chloride resistance, and microstructure properties of HSGC at an early age of 3 days and a later age of 360 days. Such enhancement in the concrete properties mainly depends on the cement replacement rates by U-POFA, temperature, and the steam curing period. It was, therefore, concluded that U-POFA played a key role in reducing the negative impact, which might have been caused by the utilization of varying SCRs.

In the reported study, the effect of slag content and curing methods on the strength development of alkaline activated (AA) silico-manganese fume (SiMnF (S)) and ground granulated blast furnace slag (GBSF (G)) blended mortar using NaOHaq and Na2SiO3aq was studied. The mixtures were prepared with 100% SiMnF (AAS100G0), i.e. control binder or 70% SiMnF plus 30% GBFS (AAS70G30), i.e. optimum binder and subjected to room-curing (CR) (25±2 °C) and heat-curing (CH) (60 °C for 24 h in oven) were examined. The raw materials and binders were characterized, while flow and compressive strength of mortar was evaluated. A linear increase in strength was noted in the room-cured specimens, regardless of binder type. The 3-day strength (42.6 MPa) of heat-cured AAS70G30CH specimens was 189 and 97% of the 3-day and 28-day strength, respectively, of room-cured specimens. However, a curing temperature beyond room-temperature did not favour the reaction of AAS100G0 system due to high Mn/Ca ratio and carbonation. It is postulated that the addition of 30% GBFS contributed to the strength and stability in the development of AASG mortar. Heat-curing of AAS70G30CH resulted in highest early-age strength due to dense microstructure induced by conspicuous embedment of Ca ions to the skeletal framework thereby increasing the amorphousity of the binder.

This study investigated the interfacial bond strength between a new Green Universiti Sains Malaysia Reinforced Concrete (GUSMRC) as a repair material and the existing normal concrete substrate (NC) using two methods of surface treatment: grooving and sandblasting. The bond strength was evaluated via the slant shear, splitting tensile, and pull-off strength tests at 7, 28, and 90 days. The results showed that the bond strength of the NC/GUSMRC composite was extremely high, especially with the sandblasting surface treatment. The slant shear results showed that the specimens with sandblasting surface treatment showed almost 1.5 times higher slant shear strength than the strength of those with the grooving surface treatment at the three tested ages. The splitting strengths of the sandblasted samples were 8.3%, 20.7%, and 18.5% higher than the strengths of the grooved samples at 7, 28, and 90 days, respectively. Similarly, the pull-off strengths of the sandblasted specimens were 2.3%, 10%, and 14.5% higher at 7, 28, and 90 days, respectively. The bond strength increased as the age of the composite increased. Therefore, GUSMRC has great potential in the rehabilitation of RC structures.

Palm oil fuel ash (Pofa) and polyvinyl alcohol fibres were used to make an alkali-activated cementitious composite mortar, which was then tested. Based on the test results, a support vector regression model was developed to estimate the effect of the alkaline activator/Pofa ratio on early compressive strength at different added water contents. The results from the model show that the mortar strength increased as the sodium silicate+sodium hydroxide/Pofa ratio increased up to an optimum, after which the strength declined considerably. The sodium hydroxide molarity and added water were also found to have a significant effect on strength. Excellent agreement was found between the model results and test results. The precision and accuracy of the developed model show its potential for reducing the challenges of acquiring experimental data.

Silicomanganese (SiMn) fume is an industrial waste whose potency in the synthesis of alkaline activated mortar is yet to be explored. The major constituents of SiMn fume are SiO2, MnO2 and K2O. SiMn fume based mortar cured at room temperature (23 ± 2 °C) was synthesized with NaOH (NH) of varied molarity (4, 8 and 12) and Na2SiO3 (NS) as alkaline activators with different ratios of NS/NH (2, 2.5 and 3). The maximum 28-day compressive strength of room temperature cured mortar of 36 MPa was achieved with combined NH-12M and NS/NH of 2.5. Utilization of only NH activator produced a low strength (6.8 MPa) mortar compared to using the combined activators due to inability of pure alkali to form condensed oligomers required for gelation. The combination of NS and NH was more workable and produced significant strength that increased with molarity of NHaq due to proliferation of silica in the base material. SEM and XRD characterizations revealed that mortar of high molarity is more crystalline and denser with well compacted matrix compared to that of mild alkali (4 M). The crystalline phase in XRD was observed at 29.5° 2θ due to the formation of Nchwaningite (Mn2+2SiO3(OH)2·(H2O)). The strength development was due to high reactivity of MnO2 with NS, especially when the ratio of NS/NH was 2.5.

This study aimed to investigate the feasibility and advantages of utilizing ternary blended binders consisting of Ordinary Portland Cement (OPC), Densified Silica Fume (DSF), and Ultrafine Palm Oil...

Corrosion of steel reinforcement is a major cause of structural damage that requires repair or replacement. Early detection of steel corrosion can limit the extent of necessary repairs or replacements and costs associated with the rehabilitation works. The ground penetrating radar (GPR) method has been found to be a useful method for evaluating reinforcement corrosion in existing concrete structures. In this paper, GPR was utilized to assess corrosion of steel reinforcement in a concrete slab. A technique for accelerating reinforcement bar corrosion using direct current (DC) power supply with 5% sodium chloride (NaCl) solution was used to induce corrosion to embedded reinforcement bars (rebars) in this concrete slab. A 2 GHz GPR was used to assess the corrosion of the rebars. The analysis of the results of the GPR data obtained shows that corrosion of the rebars could be effectively localized and assessed.

We have successfully investigated the use of a whispering gallery mode (WGM) optical micro-bottle resonator (MBR) for liquid formaldehyde (CH2O) sensing. The MBR was fabricated via the â��soften-and-compressâ�� method to create a bulge (bottle) structure with a bottle diameter of 190 I¼m. The MBR was optically excited by using a non-adiabatic 2 I¼m optical microfiber and was found to have a Q-factor of >105. The MBR was then employed to measure formaldehyde concentration within 1â��5 range and the performance was compared with a bare microfiber. The MBR sensor was found to have a sensitivity of 4.397 dB/ with 90 linearity which were superior to the bare microfiber. The MBR sensor was also found to have good repeatability and stability over a period of 60 min. This indicates that MBR sensor has a great potential to be employed as a low cost formaldehyde liquid sensor. © 2018

The strength gain of alkali-activated binders (AAB) when cured at room temperature is delayed due to the slow polymerization process. This is the major impediment in the utilization of this green concrete in cast in-situ concrete structures. In order to expand the applications of these binders to various fields of construction, attempts have to be intensified to overcome this obstacle. Incorporation of finer materials with high specific surface area to enhance the reactivity of alkali activated concrete (AAC) is one of the potential approaches to accelerate their strength gain. In this regard, nanomaterials, such as nanosilica (NS), can play a key role. Therefore, to enable curing at room temperature, incorporation of NS as partial replacement of natural pozzolan (NP) in developing AAC is the focus of this research work. AAC mixes were prepared by partially replacing NP with NS up to 7.5% by weight. The compressive strength development was monitored until 180 days of room temperature curing (23 ± 2 °C). Flexural strength and modulus of elasticity of concrete were also measured. Constitutive models relating the engineering properties of the developed AAC were formulated using regression analysis. In addition, SEM and XRD techniques were used to assess the nature of the binder formed during alkali activation. The data developed in the reported study indicated that NP, without incorporating NS, can be used as precursor material for producing AAC that could be potentially used as a construction material. However, AAC mixtures incorporating NS exhibited remarkable enhancement in the mechanical properties and microstructural characteristics. The addition of, 5% and 7.5% NS resulted in superior mechanical properties and a denser microstructure due to the greater transformation of precursor material in to polymeric compounds. The tangible outcomes of this research highlights the importance of nanomaterials in improving the properties of green building materials.

The study reports the influence of Al(OH)3 as alumina source on the compressive strength of POFA alkali-activated mortar (POFA AAM). The synthesis of the developed POFA AAM stems from the mixture proportioning of Na2SiO3(aq), NaOH(aq), POFA and Al(OH)3. At the 28th day, after 65 °C heat and laboratory curing, the compressive strength of the POFA AAM were tested. It was observed that the compressive strength of all the POFA AAM specimens with Al(OH)3 addition were lower than those of the specimens without Al(OH)3 addition. The only exception was with the POFA AAM at 2% Al(OH)3 addition in all NaOH molarities. The compressive strength losses recorded in some POFA AAM were due to weak interfacial zones creation between the activated products and the zeolitic phases, which became more apparent at higher Al(OH)3 additions. The strength development of the POFA AAM microstructure was studied with the aid of SEM/EDS, XRD and FTIR.

Volcanic ash obtained from Mount Sinabung is an aluminosilicate material that is generally available deposited in the land of Sinabung. The study focuses to investigate the effect of volcanic ash as partial replacement of ground-granulated blast-furnace slag (GGBFS) based alkaline activated mortar (AAM) in varying six ratios from 10 wt.% to 60 wt.% in terms of the compressive strength (CS) and structural characteristics. The six-mixture design of AAM was conducted with addition of alkaline activator solution (AAS) to solid material. The AAS were prepared from a combination of 10 M NaOH and Na2SiO3, whereas, solid materials consisted of GGBFS, VA and fine aggregates. The results of the experiments were analysed by CS at the age of 7, 28, and 56 days and supported by SEM characterization for the optimum mixture. The results have revealed that the least significant factor in terms of compressive strength value is the addition of volcanic ash content whereby the highest value of 93.50 MPa produced by Va 10% and the lowest of 35.80 MPa from Va 60% for all of ages day. In addition, the regression linear values show the overall compressive strength decreased slowly over the ages. Contrastingly, the addition of volcanic ash higher than 40% exhibited an increment of compressive strength. Based on SEM observation dense and continuous microstructure was observed which reflects a high degree of polymerization reactions. At the same time, no cracks were observed in the surface microstructure that shows proper aggregate-binder bonding that influences the compressive strength results finding.

One of the main aspects of sustainable engineering constructions is the recycling of byproduct materials or wastes, including those from different agricultural crops. The influence of terna...

Sustainable alkali activated mortar was developed in this study utilizing silicomanganese (SiMn) fume. SiMn fume is an industrial by-product produced during the production of SiMn alloy by carbothermic reduction. SiO2, MnO2 and K2O are the major constituents of SiMn fume. The precursor material was activated by varied concentration of NaOH (4M, 8M and 12M) and constant Na2SiO3/NaOH ratio of 2.5. Alkali activated SiMn fume mortars were cured at room temperature (23 ± 2 °C) and the maximum compressive strength of 36 MPa was achieved at a concentration of 12M NaOH. Influence of dissolution of SiMn fume with a change in NaOH concentration can be observed from the results of setting time, flow and compressive strength. Flow and compressive strength increased with an increase in the concentration of NaOH. SiMn fume can be utilized as a precursor material to develop a sustainable alkali activated cementitious binder.

Alkaline activated binders (AAB), which are the results of reaction between source aluminosilicates and alkaline activator, are an environmentally friendly binder that exhibits high compressive strength (CS). This study explores the effects of different combinations of ultrafine treated palm oil fuel ash (u-TPOFA) and fly ash (FA) on the compressive strength and structural composition changes of the u-TPOFA-FA alkali-activated binary binder mortar (AABBM). The alkaline activated mortar (AAM) was synthesized using mixtures of u-TPOFA and FA in varying ratio of u-TPOFA:FA of (100:0), (90:10), (80:20), (70:30), (50:50), (25,75) and (0:100), respectively, and the alkaline activating solution consist of a combination of Na2SiO3 and NaOH. The combination and concentration of Na2SiO3 and NaOH were constant for all mixtures. Primarily, it was found that mixture with a combination of u-TPOFA:FA of 25:75 gain the highest compressive strength (CS) of 54.82 MPa at 28 days. Therefore, the replacement of SiO2 from u-TPOFA by Al2O3 provided by FA contributes towards significant CS enhancement due to the formation of more N-A-S-H gel binder. The result observed for the gel binder formation was emphasized with XRD and FTIR analyses.

The effect of various grades of Na2SiO3 on the compressive strength (CS) development of alkaline activated binder mortar (AABM) synthesized from eggshells powder (ESP) with curing time of up to 28 days has been investigated. Three different mixtures of AABM were synthesized from the solid material and alkaline activator solution (AAS). The solid materials consisted of source material and aggregates. ESP was used as the sole source material for the AABM. The AAS was prepared from NaOH and various grades of Na2SiO3 which was characterized by their SiO2/Na2O molar ratio of 2.064 (#1), 2.27 (#2), and 3.3 (#3), respectively. The results showed that the mixture prepared with Na2SiO3 grade #1 has a higher CS than the other two mixtures. The highest CS was 12.31 MPa at 28 days. The CS development was associated with the formation of tilleyite phase as gel binder and it is in good agreement with the XRD analysis.

The use of non-traditional cement replacement materials such as POFA in concrete has attracted many researchers, likewise this study attempted to keep investigating the ability of utilizing the ultra-fine treated palm oil fuel ash (u-TPOFA) as supplementary cementitious materials (SCMs) in Portland cement mortar. The u-TPOFA was used as SCM to produce binary blended cement mortar (BBCM) at different replacement levels of 30, 40, 50 and 60 wt% of ordinary Portland cement (OPC). The compressive strength (CS) was evaluated for all the cured samples at various ages of 3, 7, 14, and 28 days. The test results showed that the CS development improved with curing age as expected in all cases and a clear influence of u-TPOFA replacement levels on CS of the BBCM was observed. The CS at early ages of the BBCM was lower than the control binder mortar (CBM). However, the CS started to increase after 7 days of curing. The highest CS among all the BBCM was observed with u-TPOFA replacement level of 30 wt% from OPC which achieves 81.7 MPa at 28 days, whereas the CBM registers the highest CS of 83.73 MPa. The results for the CS concur with the phase changes based on XRD and TG analyses. The changes in CS was as a result of the formation of more C-S-H and C-A-S-H gel binders and less Ca(OH)2 content remained in the structure.

Development of alkali-activated binder (AAB) is fast becoming a viable alternative to ordinary portland cement (OPC). However, key engineering properties of such a binder depend strongly on the chemical composition and fineness of the source materials in addition to the concentration of alkaline activators. In order to improve the reaction kinetics and subsequently, the mechanical strength of alkali activated concrete (AAC), nano-SiO2 was proposed as a partial replacement to natural pozzolan (NP) in this study. As the composition of alkaline activators also plays a vital role on the properties of AAC, trial mixtures were prepared with varying sodium silicate to sodium hydroxide (SS/SH) ratio. Subsequently, NP was partially replaced with nano-SiO2 in the selected mix to enhance the properties further. Fresh properties, such as, setting time of alkali-activated pastes (AAP) and the workability in terms of flow of mortar were determined. Evolution of compressive strength of concrete cured at 60 °C was monitored. Scanning electron microscopy (SEM) and X-ray diffration (XRD) were utilized to determine the morphology and mineralogy of the AAP, respectively. In addition, FTIR was used to identify functional groups formed in the AAP. The study reveals that a SS/SH ratio of 2.5 was suitable in achieving superior strength. AAC prepared using NP and nano-SiO2 exhibited improved strength and microstructural characteristics. However, 5% nano-SiO2 showed significant enhancement in the compressive strength and microstructural characteristics as compared to those prepared with other replacement levels. Consequently, the results of this study provides important information on developing NP-based sustainable building material with remarkable enhancement in the properties by adding nano-SiO2.