Types Of Fine Aggregates Research Articles

Synthesis of a novel one-part alkali-activated material from solid wastes salt sludge and soda residue

In this paper, salt sludge (SS), a solid waste from sodium hydroxide production, was activated at high temperature for the first time. It was combined with soda residue (SR), a solid waste from sodium carbonate production, as a solid activator to activate the solid aluminosilicate precursor, blast furnace slag (BFS). This process developed a novel one-part alkali-activated material, termed salt sludge and soda residue co-activated blast furnace slag cementitious material (SRB), which effectively utilizes solid wastes. The effects of ratios of calcined SS (CSS) to SR, fine aggregate types, and curing methods on the physical and mechanical properties of SRB were investigated. The composition of the hydration products was characterized using X-ray diffraction (XRD), thermogravimetric analysis (TGA), and fourier transform infrared spectroscopy (FTIR), while the hydration process during the setting stage was examined with 1H low-field nuclear magnetic resonance (1H LF NMR). The influence of mix ratio, fine aggregate type, and curing method on the microstructure of SRB was analyzed using scanning electron microscopy (SEM). The results showed that the synergistic activation of BFS by CSS and SR was significantly more effective than individual activation. At the optimal mix ratio (CSS:SR:BFS = 15:15:70), the 3/28 days compressive strength of SRB was 14.3/53.7 MPa. The primary hydration products were C-(A)-S-H gels, along with Friedel's salt, ettringite, and hydrotalcite crystals. Using manufactured sand (MS) as a fine aggregate reduced mortar fluidity compared to river sand (RS) but enhanced the interfacial transition zone (ITZ) with the hardened paste, resulting in a denser microstructure. Heat curing promoted hydration product generation, increasing early (3 days) strength by a factor of 2.5. However, the rapid accumulation and insufficient diffusion of hydration products adversely affected the later strength.

Effects of recycled sand and shell sand as sand replacement on the dynamic properties of seawater sea-sand recycled aggregate concrete

This study utilizes recycled sand and shell sand to replace sea-sand in seawater sea-sand recycled aggregate concrete (SSRAC) and explores their dynamic compressive properties. A total of 28 sets of specimens were designed, and their stress-strain curves under different strain rates were analyzed. The findings indicated that the dynamic increasing factor (DIF) of peak stress in SSRAC reached its peak at a 50% replacement ratio of recycled sand, exhibiting a 3.9% to 7.7% increase compared to a 0% replacement ratio. Conversely, there was an overall decreasing trend in the DIF when the replacement ratio of shell sand increased. Using recycled sand resulted in an average reduction of approximately 45% in the elastic modulus of the interfacial transition zone (ITZ), while the introduction of shell sand slightly increased that of it. Finally, considering strain rate effects, a dynamic compressive prediction model for SSRAC with different types of fine aggregates was established.

Properties of mortar according to substitution rate of ferro-nickel slag powder

This study analyzes the properties of cement mortar according to the substitution of fine ferro-nickel slag powder in various types of fine aggregate, with the aim of recycling industrial waste. When using a ferro-nickel slag powder as the admixture of cement mortar, it is determined that substitution rates of 30% and higher are unsuitable for use as mortar. In order to solve this problem, it is believed that it is necessary to explore means to improve the initial strength degradation that results when fine ferro-nickel slag powder is mixed. Furthermore, the differences in carbon dioxide reduction according to fine ferro-nickel slag powder substitution rates were found to be minimal, and it is thought that additional performance analysis is necessary.

Bond-Slip Constitutive Relationship between Steel Rebar and Concrete Synthesized from Solid Waste Coal Gasification Slag

Bond performance served as a crucial foundation for the collaboration between concrete and steel rebar. This study investigated the bond performance between coal gasification slag (CGS) concrete, an environmentally friendly construction material, and steel rebar. The effects of fine aggregate type, steel rebar diameter, and anchorage length on bond performance were examined through bond-slip tests conducted on 16 groups of reinforced concrete specimens with different parameters. By utilizing experimental data, a formula for the bond strength between steel rebar and CGS concrete was derived. Additionally, the BPE bond-slip constitutive model was modified by introducing a correction factor (k) to account for relative protective layer thickness. Findings indicated that substituting 25% of manufactured sand with coal gasification slag did not cause significant adverse effects on concrete strength or bond stress between concrete and steel rebar. The effect of steel rebar diameter on the ultimate bond stress was not obvious, whereas when the steel rebar diameter was fixed; the increase in anchorage length led to uneven distribution of bond stress and eventually reduced the ultimate bond stress. The modified bond-slip constitutive model agreed well with the experimental values and was able to more accurately reflect the bond-slip performance between CGS concrete and steel rebar. This study provided a theoretical basis for the conversion of CGS into a resource and for the application of CGS concrete.

Production of rubberized concrete utilizing reclaimed asphalt pavement aggregates and recycled tire steel fibers

The integration of waste tire elements into concrete, specifically granular rubber and discrete steel fibers, signifies a substantial advance in the pursuit of sustainable alternatives for rigid concrete pavements. This incorporation not only improves the ductility of rigid concrete pavements, but also augments their energy absorption capabilities. Similarly, replacing natural aggregates in concrete with reclaimed asphalt pavement (RAP) aggregates makes a large contribution to the reduction of negative environmental impacts, while conserving natural resources from depletion. This investigation explores the potential application of recycled rubber particles from waste tires (WTRR) and RAP aggregates as partial substitutes for natural fine aggregates, and evaluates their impact on the performance of rigid concrete pavements. Eight mixes were cast, each with two variables: (i) fine aggregate type (fine rubber (FRu) aggregates, fine asphalt (FAs) aggregates, and combinations of both types of aggregate) replacing 50 % of the natural fine aggregate; and (ii) waste tire recycled steel fibers (WTRSF) content (0 and 40 kg/m3). The axial compressive stress–strain, flexural load–deflection, and direct shear strength behaviors, together with the dry unit weight and volume of permeable voids for all concrete mixes were investigated and compared. The results show that, although the flexural and shear strengths decrease with the inclusion of FRu and/or FAs, the use of WTRSF noticeably mitigates the losses in strength that arise from the use of WTRR and/or RAP aggregates alone. The inclusion of WTRSF enhances the strain capacity of the concrete and allows the development of adequate post-peak energy absorption capacity in flexural and shear loading. Additionally, the dry unit weight of the proposed composites decreased by as much as 8 %, and their volume of permeable voids lies within the limits of high-durability concrete mixes (9–12 %). Hence, the proposed sustainable concrete composites are promising composites for rigid concrete pavement construction.

Improvement in Mechanical Properties of Completely Decomposed Granite Soil Concrete Fabricated with Pre-Setting Pressurization.

This paper investigates the effectiveness of applying continuous high-compression pressure on the initial setting of fresh concrete to produce hardened concrete materials with excellent mechanical properties. A novel experimental apparatus was self-designed and used for the pre-setting pressure application. The utilization of the completely decomposed granite (CDG) soil as an alternative aggregate in concrete production was also explored. A total of twenty-eight specimens were fabricated using two types of fine aggregates, six mix ratios, two initial pressure values, and two distinct durations of the initial pressure application. The density and uniaxial compressive strength (UCS) of the specimens were examined to evaluate their mechanical qualities, while micro-CT tests with image analysis were used to quantify their porosity. The results indicated that the 10 MPa initial pre-setting pressurization can effectively eliminate the excess air and voids within the fresh concrete, therefore enhancing the mechanical properties of the hardened concrete specimens of various types. Compared with non-pressurized specimens, the porosity values of pressurized specimens were reduced by 73.11% to 86.53%, the density values were increased by 1.43% to 8.31%, and the UCS values were increased by 8.42% to 187.43%. These findings provide a reference for using a continuous high pre-setting compression pressure and using CDG soil as an aggregate in the fabrication of concrete materials with improved mechanical performance.

Effect of different types of fine aggregates on fatigue resistance and self-healing of fine aggregate asphalt matrices

Fatigue cracking is one of the most common types of distress in asphalt pavements. Each asphalt concrete (AC) constituent and its interactions are relevant to characterize the resistance to fatigue cracking of the ACs. Also, for the selection of materials, it is essential to consider not only the capacity of the material resist to fatigue cracking but also its ability to heal. Materials owning self-heal properties can enlarge the ACs fatigue life. Many former studies investigated the self-healing of bituminous materials at the binder level. However, this material property can be dependent on the binder-aggregate interactions. Thus, the current work aims to evaluate the influence of using different fine aggregates on the fatigue cracking resistance and self-healing capacity behavior of fine aggregate matrices (FAMs). First, granite, basalt, and mica schist aggregates were subjected to physical, morphological, and mineralogical characterization. Then, three FAMs were fabricated with the same asphalt binder and these different fine aggregates. To evaluate the fatigue cracking resistance and self-healing capacity of the FAMs, frequency sweep and time sweep tests were conducted. The simplified viscoelastic continuum damage (S-VECD) theory was used to interpret the results of those tests. The mineral composition of the aggregates impacted the stiffness and the fatigue life of the FAMs. However, there was no significant influence of the aggregates on the self-healing capacity of the FAMs, since there was no significant increase in the fatigue life of the materials after the resting periods in the time sweep tests.

Mechanical properties and fracture behavior of seawater-mixed sea sand recycled aggregate concrete

Despite their undeniable potential for promoting sustainability in construction materials, the characteristics of recycled aggregates (RCA), seawater, and sea sand may vary significantly, thereby affecting their use in structural concrete. This study exploits these materials to investigate their performance in producing sustainable concrete and establishing its mechanical and fracture behavior. The so produced material, referred to as seawater sea sand recycled aggregate concrete (SSRAC) could lend a hand in widening the usage of RCA and sea sand in a variety of applications where the use of ever-depleting natural materials as concrete constituents becomes an issue. Consequently, the variables of the study include the type of water (fresh versus seawater), type of coarse aggregate (RCA versus natural coarse aggregate, NCA), and the type of fine aggregate (dune sand versus sea sand). For each water type, three concrete mixtures are produced using NCA-dune sand, RCA-dune sand, and RCA-sea sand combinations. Analyses of the mechanical characteristics of the concrete, including compressive strength, flexural strength, modulus of elasticity, and fracture toughness, were conducted based on experimental tests. X-ray Diffraction (XRD) and Scanning Electron Microscopy (SEM) analyses were also conducted on the designed specimens to investigate their microstructure. In terms of fracture characteristics, the use of seawater resulted in improvement in the fracture toughness. The use of recycled aggregate along with seawater resulted in improved compressive strength. However, natural aggregate concrete (NAC) showed higher flexural strengths than recycled aggregate concrete (RAC). The results also revealed that the addition of sea sand had a detrimental impact on all mechanical characteristics. Thus, optimizing the concrete composition in which the investigated materials partially replace the conventional concrete constituents is required in order to consider alternative constituents to generate sustainable concrete for practical applications.

Enhancing the resistance of cementitious composites to environmental thermal fatigue using high-volume fly ash and steel slag

Daily fluctuations in environmental temperature induce thermal fatigue and cause degradation in concrete structures. This study introduces a novel approach of utilizing high-volume fly ash, steel slag fine aggregates, and basalt-polypropylene fibres to prevent degradation against environmental thermal fatigue (ETF). Five mixes were considered with variations in fine aggregate type, fibre length and volume. The compressive and flexural strengths were analysed after exposure to 60, 120, 180, 240, and 300 ETF cycles between 20 and 60 °C (at constant relative humidity). The residual compressive strength of mix with 100 % river sand and 100 % steel slag as fine aggregates was ∼106 % and ∼112 % respectively after 300 ETF cycles. The developed cementitious composites performed significantly better than the mixes utilized in the existing literature. The mix with 100 % steel slag aggregate even demonstrated a continual rise in compressive strength as opposed to mixes with river sand whose strength declined after 180 or 240 ETF cycles. Flexural strength also improved up to 180 ETF cycles and then started to decline in all mixes. A thorough microstructural analysis was also conducted using scanning electron microscopy, differential scanning calorimetry, and mercury intrusion porosimetry to gain further insights into the underlying mechanism of the newly introduced matrix composition against ETF.

ANALYSIS OF THE QUALITY OF FABA (FLY ASH BOTTOM ASH) BASED CONCRETE AS AN FINE AGGREGATE SUBSTITUTE WITH REFERENCE TO MIXTURE PROPORTION IN WORK UNIT PRICE ANALYSIS

In this research, the author used FABA (Fly Ash Bottom Ash) waste as an alternative to fine aggregate. This research can determine the physical properties of faba aggregate with the results of sieve analysis testing of faba aggregate which has a fineness modulus value of 2.34 which is included in the medium fine aggregate type. Testing for water content in faba fine aggregate in SSD conditions was 3.09%. Faba fine aggregate sludge content is 0%. Testing the organic substances on the faba fine aggregate showed that the NaOH color was reddish brown, because it needed to be washed first before being used as a concrete mixture. The face dry specific gravity of faba fine aggregate is 2.2 gr/cm2. Therefore, faba aggregate can be used as a substitute for sand because it has physical properties that meet the requirements as fine aggregate. Results The final compressive strength of faba concrete and normal concrete as a control at the age of 7 days and 28 days has reached the planned quality, but the compressive strength at normal concrete (control) is higher than faba concrete. With the results of the standard deviation values ​​at 7 days and 28 days, it is included in perfect workmanship condition because it has a standard deviation value of less than 3 MPa. The results of the concrete flexural strength test were only normal K300 concrete with a flexural strength of 4.60 MPa, which complies with SNI 2847:2013, namely producing a minimum flexural strength of fs = 4.4 MPa. Normal concrete has a much higher flexural strength than faba concrete, and the higher the quality of the planned concrete, the greater the resulting flexural strength of the concrete.

Comparison of fresh and hardened properties of concrete made with various artificial and natural sands

Concretes made with different fine aggregates (natural river sand, artificial crushed sand, artificial gravel sand and a hybrid sand (50% river sand and 50% gravel sand by mass)) were experimentally investigated. The concretes were found to have little differences in compressive strength and elastic modulus (less than 6.4%). Compared with the concrete made with natural river sand, the concretes made with artificial sands demonstrated higher flexural strengths (3.5–11.1%) and splitting strengths (4.4–12.8%) at 28 days, but lower workability (21.4–35.7%), water permeation resistance (34.3–53.7%) and abrasion resistance (2.9–20.6%). The compressive, flexural and splitting tensile strengths of the concretes increased with time under water curing. Under sulfate attack, the compressive strengths of the concretes were enhanced at 56 days but reduced at 90 days. In comparison with water curing, the reductions in compressive strength due to sulfate attack were 2.6–7.7% at 56 days and 11.8–24.4% at 90 days. Weibull distribution analysis was conducted to explore the sensitivity of concrete strength to the type of fine aggregate.

Comparison of Compressive Strength of Concrete Produced with Different Types of Fine Aggregates

The most often used building material worldwide is concrete. It is made by mixing water, coarse aggregate, binding ingredients, and fine aggregate in the right amounts. Because it provides a good sign of the general quality of the concrete and is very simple to test, particularly under uniaxial compression, concrete strength is a commonly examined attribute. Concrete’s compressive strength serves as the primary criterion for structural designs, and fine aggregate has a significant impact on compressive strength as well. The three samples used for this research—quarry dust, erosion-deposited sand, and borrow pit sand—were subjected to sieve analysis in order to compare the compressive strengths of concrete made with various types of fine aggregate. 36 cubes, twelve for each sample in the mix ratio of 1:2:4, were cast. The samples underwent a compressive strength test after curing for 7, 14, 21, and 28 days by complete submersion in water. With compressive strengths of 9.93N/mm2 for quarry dust sand, 9.03N/mm2 for borrow pit sand and 8.0N/mm2 for erosion deposited sand respectively, the concrete made with quarry dust had the maximum compressive strength, followed by that made with borrow pit sand and erosion-deposited sand. It is recommended that quarry dust is considered suitable out of the samples tested for concrete production based on this research findings.

Research on surface treatment technology for quickly improving the skid resistance of tunnel concrete pavement.

In order to solve the problem that the skid resistance of concrete pavement in tunnel deteriorates rapidly, which is easy to cause traffic accidents, the anti-skid rapid elevation technology of surface treatment is proposed. Wear tests were used to investigate the effects of concrete surface roughness, properties of modified emulsified asphalt binder and anti-skid fine aggregate type on long-term skid resistance of treated surfaces. The results show that the four coarsening methods of fine milling, milling, grooving and brooming can improve the skid resistance of concrete, and the skid resistance durability of fine milling and milling is better. The adhesive property of modified emulsified asphalt is the best when the content of water-based epoxy resin is 20%. In different aggregates, the anti-skid effect is better when silicon carbide is used as anti-skid aggregate and the particle size is 0.6mm:0.3mm = 2:3. The method of fine milling of concrete surface + spraying epoxy emulsified asphalt + spreading silicon carbide can effectively improve the anti-skid performance of the original concrete pavement, and the feasibility of the scheme is verified by the test road. The research results have a good reference value for improving the skid resistance of tunnel concrete pavement.

Relação entre a performance de placas de concreto permeável com escória de aciaria e as propriedades de forma de agregados graúdos

Abstract The growth of cities affects their permeable surface, which can unbalance hydrological cycles. The pervious concrete can be a viable solution to combat urban environmental impacts in this subject. This type of concrete can be told apart by the presence of interconnected pores and its drainage capacity. This paper aims to analyze the relationship between aggregate shape, mechanical resistance, and permeability of pervious concrete slabs containing steel slag. A Digital Image Processing (DIP) based method was used to measure aggregate shape properties. Three different mixes, using three types of coarse aggregate (gravel 12.5 mm, gravel 9.5 mm, and coarse steel slag), and a type of fine aggregate (fine slag) were tested, and flexural strength, flow, and permeability coefficients were obtained for the slabs. Results showed the potential of using steel slag, with higher flexural strength results (4.61 MPa). Indications of the relationship between aggregate shape parameters and slab properties were determined, with more polished, more angular, and more spherical material resulting in higher flexural strength values and lower permeability coefficient. The inverse relationship between the slabs’ permeability parameters and flexural strength was observed.

Influence of fine aggregate types for the achievement of concrete quality

Fine aggregates in the form of sand are granulated materials, which generally measure between 0.0625 to 2 millimeters. Sand as a fine aggregate mixed with cement and water becomes a concrete mixture that has a role in the strength of construction. This study aims to determine how much influence the fine aggregates or sand of four different mining sites have on the compressive strength of concrete. The method used is an experiment, based on the results of laboratory tests of compressive strength tests at the age of concrete 7, 14 and 28 days for fc’25 or 25 MPa quality concrete with a mix of designs for fine aggregates from Leles sand, Kuyamut sand, Cikamiri sand, and Cilopang sand, Garut Regency West Java Province Indonesia. The aggregates tested include moisture content, sludge content, organic content, dry saturation, waand ter absorption affects the quality of concrete and improves quality strength with the same treatment for laboratory testing. The results of the analysis with 28 days of concrete compressive strength testing obtained the achievement of the highest concrete strength, namely with Cilopang sand 27 MPa, allowed by Kuyamut sand 26 Mpa, Leles sand 25 MPa and Cikamiri sand 23 MPa. Based on the results of concrete strength testing for up to 28 days, there are three sources of fine aggregates that can reach a minimum of fc’ 25, and there is one sand source that has a compressive strength value of concrete.

Mechanical and shrinkage performance of steel fiber reinforced high strength self-compacting lightweight concrete

This study investigated the effects of mixture proportion on the mechanical and shrinkage behaviors of steel fiber reinforced high strength self-compacting lightweight concrete (SHSLC) mixtures incorporating bottom ash aggregates for internal curing. In this study, different types of fine aggregates, fine aggregate ratios, supplementary materials such as silica fume (SF) and colloidal nano-silica (CNS), and four types of steel fibers were considered to develop SHSLC. The self-compacting characteristics of concrete were evaluated by means of slump flow, J-ring flow, and V-funnel tests. The test results indicate that incorporation of SF and CNS had a positive effect on the mechanical properties, but 4% incorporation of CNS decreased workability and strength due to the agglomeration of mixture. The addition of steel fibers improved compressive strength, and flexural toughness of SHSLC, but reduced the flowability and passing ability with increased fiber contents. Due to the internal curing from coarse bottom ash, significant reduction of autogenous shrinkage up to 33% was observed, whereas 7% for drying shrinkage. The incorporation of fibers reduced the autogenous and drying shrinkage up to 31% and 22% compared with non-fiber reinforced concrete, respectively. Finally, the autogenous shrinkage behavior was simulated with several models in the literature, and a model for high strength self-compacting lightweight concrete with and without fibers considering equivalent age was proposed.

Influential factors on mechanical properties and microscopic characteristics of underwater 3D printing concrete

Underwater 3D Printing Concrete (U3DPC) technology can be a promising approach to address the challenges of renewable marine energy and coastal protection. Conducting extensive research on the mechanical properties of U3DPC is crucial for its successful implementation. This study investigates various factors, including printing environment, construction methods (mold-cast and printing), curing age, and material composition, regarding their significance on the mechanical properties of U3DPC. The compressive strength, anisotropy, interlayer bonding, and interface microstructure are evaluated. The research findings reveal that compared to casting specimens in air, the printing method and water environmental factors result in approximately 20% and 15.1% reduction in the compressive strength of U3DPC, respectively. U3DPC exhibits different anisotropic variations compared to specimens printed in air, attributed to weak interlayer bonding interfaces caused by external water. The influence of material components on the interlayer bonding strength of U3DPC has a critical threshold that should not be exceeded; otherwise, it weakens the interlayer bonding. The variation in fine aggregate types and fibers leads to changes in interlayer interface roughness, where excessive roughness captures more ambient water due to the “dog-tooth overlapping” structure, thereby reducing the adhesive capacity. The pore distribution reveals the underlying mechanism of how interface roughness affects interlayer bonding.

INFLUENCE OF FINENESS MODULUS AND PREHEATED SAND ON COMPRESSIVE STRENGTH OF ALKALI ACTIVATED GEOPOLYMER MORTAR

Geopolymer mortar is a complex material, and its strength and durability fundamentally depend on its main constituent properties, grading and grain size distribution of a fine aggregate. The Fineness Modulus (FM) of fine aggregates (sand) is an empirical figure obtained by adding the total percentage of the sample of sand retained on each of a specified series of sieves and dividing the sum by 100. The purpose of this research is to analyze the effect of the Fineness Modulus (FM) of preheated sand at 100°C on geopolymer material (GPM) compressive strength (Cs). The current research used natural river sands of fineness modulus 1.85, 2.41, 2.79, 3.32 to prepare geopolymer material paste. The 36 cube specimens of 50 x 50 x 50 mm size were used to calculate the Cs of GPM paste at 3 h, 1 d, and 7 d. All specimens were kept in hot curing at 40°C for 3 h. The outcomes of the research showed that the sand fineness modulus has a significant impact on the GPM flow rate (%). The results indicated that rising the fineness modulus of sand enhanced the flow rate (%) of GPM paste. The GPM paste made with preheated sand of FM 1.85 (fine sand), and FM 2.79 (medium sand) at 100°C attended the highest compressive strength growth rate (%)and showed up to 47% and 51%, 85.6% and 87.27% increased in compressive strength in 3 h and 1 d, accordingly. Additionally, the fineness modulus has a significant impact on the Cs of GPM paste in the case of preheated sand. Fine sand and mild sand are the best type of fine aggregate to develop early-high-strength geopolymer material.

Analysis Of Compressive Strength Of Foam Mortar With The Use Of Teratak Buluh Sand And Ringgit Sand

The core material in the manufacture of lightweight concrete (foam mortar) is influenced by the composition of the mixture of fine aggregate. The purpose of the study was to compare foam mortar with foaming agent using two types of fine aggregates from different sources, namely Teratak Buluh Sand, Kampar and Ringgit Sand, Indragiri Hulu. This study focuses on testing the properties of fine aggregate, flow value, bulk density and Unconfined Compression Strength (UCS) of foam mortar. The fine aggregate of Teratak Buluh has a mud content value of 0.50% while the ringgit sand silt content value is higher with a 1.92% mud content percentage value where the maximum silt content value is 3%. In this study, both types of aggregates had variations in the mixture of sand to cement, namely 18/82%; 16/84%; 15/85%; 14/86% and 12/88%. The flow value in a mixture of 14/86% Teratak Buluh Sand and a mixture of 12/88% ringgit sand has a flow value of 19.00 cm which is the highest value of the five variations. Teratak Buluh sand mixture of 14/86% has a higher value than the five variations, which is 781.67 Kg/m3 while ringgit sand has the highest density value of 758.12 Kg/m3 in a mixture of 12/88%. The value of Unconfined Compression Strength (UCS) using Teratak Buluh sand is superior when compared to the use of ringgit sand. The average value of the Unconfined Compression Strength (UCS) of lightweight foam mortar material from the use of mixed teratak buluh sand of 14/86% (1136.80 kPa) and 12/88% (1175.78 kPa) has the highest value which is close to the reference Unconfined Compression Strength (UCS) of the mixture. 15/85% (1253.73 kPa) while the mixture was 18/82%; 16/84% Teratak Buluh and 18/82%; 16/84%; 15/85%; 14/86%; 12/88% ringgit sand has the lowest f Unconfined Compression Strength (UCS) which does not meet the design Unconfined Compression Strength (UCS) of 1000 kPa and 800 kPa based on the SE-PUPR-46-SE-M-2015 specifications.

Development of Geopolymer Mortars Using Air-Cooled Blast Furnace Slag and Biomass Bottom Ashes as Fine Aggregates

The aim of this study is to compare the mechanical and physical properties of different geopolymer mortars made with granulated blast furnace slag as a geopolymer source material, NaOH (8 M) as the activating solution, and three different types of fine aggregates (air-cooled blast furnace slag, biomass bottom ashes, and silica sand). The samples were made with an aggregate/geopolymer ratio of 3/1, and physical (density and mercury intrusion porosimetry), mechanical (compressive and flexural strength), and acid attack resistance were determined. When air-cooled blast furnace slag is used, the mechanical and acid attack properties are improved compared with silica sand and biomass bottom ashes because of the existence of amorphous phases in this slag, which increase the geopolymer reaction rate despite the particle size being higher than other aggregates. It can be highlighted that the use of ACBFS as a fine aggregate in geopolymer mortars produces better properties than in cement Portland mortar.