Effect Of Fine Aggregate Research Articles

Effect of Fine Aggregates and Mineral Fillers on the Permanent Deformation of Hot Mix Asphalt

Conventional asphalt pavement is the dominant mode of passenger and freight traffic in Pakistan. As a result, asphalt pavements suffer from various failures, where rutting, corrugation, and fatigue cracking are significant. Fine aggregates and mineral fillers play a pivotal role in providing structural integrity in asphalt pavements when subjected to traffic and the environment. The current study aims to examine the effects of various locally accessible fine aggregate and mineral filler materials on the interlocking properties of asphalt mixtures in relation to internal friction angle, rutting resistance, and controlling environmental pollution as an indirect benefit, thereby reducing wastes. Four distinct asphalt samples were prepared using cinders, stone dust, natural sand, and surkhi as fine aggregates and mineral fillers, as a full replacement, as per ASTM D1559, confirming the Asphalt Institute’s gradation for asphalt wearing course. Optimum binder contents (OBC) of 4.40%, 4.1%, 6.57%, and 6.63% by weight of Marshall specimen were concluded for asphalt samples containing stone dust, natural sand, cinder, and surkhi, respectively. The results revealed that surkhi, natural sand, stone dust, and cinder all showed a diminishing tendency in developing interlocking properties in asphalt mixtures at internal friction angles of 35°, 33.7°, 32°, and 28.4°, respectively. The wheel tracking test results revealed that the asphalt samples made with surkhi as fine aggregates and fillers have the highest rut resistance, whereas samples made with cinders as fine aggregates and fillers have the lowest rut resistance. The direct shear test showed that fine aggregates with a larger angle of internal friction are significantly more stable in terms of rut resistance than fine aggregates with a smaller angle of internal friction. The current research will help to prevent pavement rutting and corrugation by adding surkhi into asphalt pavements, with the reduction in brick kiln waste providing an indirect benefit.

Effect of fine aggregate on fluidity and mechanical properties of wet shotcrete

Air-entrained wet shotcrete improves the pipeline transportation efficiency of concrete. The characteristics of the fine aggregate in the mix have different effects on the fluidity and mechanical properties of air-entrained wet shotcrete. The effects of four different properties of fine aggregates (mud content, sand ratio, water content and particle size) on the fluidity and mechanical properties of air-entrained wet shotcrete were studied, with particular attention paid to the sand ratio and mud content. The fluidity and mechanical properties of wet shotcrete were optimum when the sand ratio of the fine aggregate was 0.56 and the water content was 3%. The fine aggregate should have a reasonable particle size as far as possible. Montmorillonite in the mud inhibited the fluidity and mechanical properties, so mud content should be kept as low as possible. The results of this work provide a reference for the practical application of air-entrained wet shotcrete, so as to better deal with pipe blockage.

Effect of fine aggregates on the strength and hydraulic properties of pervious concrete

In this study, the effect of inclusion of fine aggregates on the strength and hydraulic properties of pervious concrete have been investigated. A total of three mixes were casted using three different proportions of fine aggregates at a constant water to cement ratio and powder to aggregate ratio of 0.35 and 0.16 respectively. The partial inclusion of Natural Fine Aggregates (NFA) in place of Natural Coarse Aggregates (NCA) was done in the proportion of 0%, 10% and 20% respectively. The influence of NFA was investigated by performing workability, permeability and compressive strength at different curing periods. It was observed from the results that incorporation fine aggregates in pervious concrete up to 20% increases the compressive strength values significantly. A maximum increment of 17% in compressive strength was seen at 20% of NFA at 28 days of curing. Moreover, it was observed from the microstructure observations that a dense and layered calcium-silicate- hydrate (C-S-H) was seen for mix M20. It was further investigated from energy dispersive x-ray spectrometer that 50-60% of volume was occupied by C-S-H gel for mix M20.

Effect of Fine Aggregate Gradation on Macro and Micro Properties of Cold Recycling Mixture Using Emulsified Asphalt

In order to explore the influence of fine aggregate on the macro and micro properties of cold recycling mixture using emulsified asphalt (CRME), mechanical and microscopic property tests were carried out. The indirect tensile strength (ITS), unconfined compressive strength (UCS) and triaxial shear strength of different fine aggregate gradation was measured for analyzing the effects of fine aggregate on the mechanical strength, triaxial shear resistance and fracture energy of CRME. Meanwhile, the surface morphologies and air voids distribution of different CRME were observed by scanning electron microscopy (SEM) and X-ray computed tomography (X-ray CT). The results show that fine aggregate has a significant effect on the mechanical strength and shear resistance of CRME. With the same water and asphalt content, the fracture energy and failure strain of the mixture with less fine aggregate (G3-2) decreased by 16.2% and 18.2%, respectively. The less content of powder there was, the fewer cement hydration products there were due to some cement being coated by emulsified asphalt and the “cement hydration products fiber” length being shorter. Approximately 70% of the AFt hydration products in the G3-2 mixture were in the range of 1–4 μm, while those in the G1 mixture were in the range of 4–8 μm. With the increase in filler content, the number of air voids in the volume range of 0.5 mm3 ≤ V < 5 mm3 in CRME decreased, and the number of air voids in the volume range of V < 0.5 mm3 significantly increased, while the equivalent radius of air voids decreased slightly with the increase in filler content.

Effect of Fine Aggregate Sources on Compressive Strength of Cement Concrete

The cause of failure of structure made from cement concrete is due to use of low-quality ingredient which is used directly without testing its properties and without studying its suitability in production of different grade of concrete mix. The aim of this study is to presents that the effect of fine aggregates from different sources on compressive strength of cement concrete. For this study four fine aggregate sources were taken. Altogether 48 concrete cubes of M20 grade were prepared from different sixteen combinations of these four fine aggregate sources. The different properties were founded by conducting different laboratory tests for fine aggregates from different sources and the compressive strength test of 48 cubes was conducted.The test results showed that properties of fine aggregate sources such as fineness modulus, loose bulk density, specific gravity, water absorption and Materials Finer than 75 μm were founded in the range of (3.17-3.88), (1508.33-1604.17) kg/m3, (2.57-2.66) %, (1.60-1.92) % and (2.74-7.47) respectively. Compressive strength test of all 48 samples were cross the minimum strength provided by M20 grade and it is ranges from 20.64 N/ mm2 to 32.47 N/ mm2. Different value of mean compressive strength was obtained for all sixteen combinations of aggregates form each other. The fine aggregate from Chisang source achieved more value of average compressive strength when mix with other four different coarse aggregate sample than other three sources. Significance difference in mean compressive strength of concrete made from different fine aggregates source was concluded by the Two-way ANOVA test results. This research work concluded that all four fine aggregate sources used in this study and concrete made from these sources can be used for residential building construction propose and other construction work which required strength provided by M20 grade of nominal mix concrete.

Durability of concrete made with natural granular granite, silica sand and powders of waste marble and basalt as fine aggregate

In this study, the durability of concrete made with natural granular granite, silica sand and powders of waste marble and basalt as fine aggregate, was taken into consideration. Limestone was used as coarse aggregate in the production of samples. The properties considered were the compressive strength, resistance to abrasion, freeze-thaw property, capillary water permeability and sulfate resistance. It was observed that the durability property of the concrete made with natural granular granite, silica sand and powders of waste marble and basalt as fine aggregate, was superior to the conventional control concrete. The effect of fine aggregate on the durability of concrete was evaluated. It is understood that the proposed mix provides a better condensed matrix. Moreover, it was observed that the fine aggregate type and its incorporation ratio, also, have great effect on the level of durability. Finally, the results show that addition of natural granular granite, silica sand and powders of waste marble and basalt yields a perfect less permeable concrete.

Thermal Conductivity of Aerated Concrete Based on Response Surface Method

Aerated concrete (AC) is widely used in the construction industry due to lightweight and advanced thermal properties. In this research, thermal conductivity (λ) of non-autoclaved AC was characterized with Response Surface Methodology (RSM). The effect of fine aggregates with different Al2O3 contents on the minimal λ value was analyzed using RSM. Test results show that sand with higher Al2O3 content has more influence on lower λ of AC. The regression models were significant and applicable to analyzation and prediction of λ of AC with good accuracy.

Investigation on effect of aggregate on three non-destructive testing properties of concrete subjected to sulfuric acid attack

In order to investigate the effect of aggregates on the concrete sulfuric acid resistance, accelerated corrosion experiments were conducted with four types of concretes composed of coarse and fine aggregates with two different chemical compositions. All the concretes with the same water/cement ratio of 0.45, and the pH value was kept in the range of 0.93–0.97. With continuous monitoring of each concrete specimen, corrosion depth, mass loss, and dynamic modulus elasticity loss were calculated. The results showed that the dynamic modulus of elasticity loss can be regard as an acceptable indicator for evaluating the resistance of concrete to sulfuric acid attack as well as corrosion depth and mass loss. A regression model proposed in this paper could provide good predictions. Concrete with marble aggregates rich in calcium carbonate have better performances in sulfuric acid solution than that with inert aggregates. Effect of fine aggregate on concrete sulfuric acid corrosion rate is more significant than coarse aggregate in the term of corrosion depth, mass loss, and dynamic modulus of elasticity loss.

Role of fine aggregates on mechanical properties of mortar

As new types of cement-based composites that require properties other than compressive strength have been developed, the properties of the matrix need to be tailored considering the targeted performance of the composites. This study examines the effect of fine aggregates in the matrix on mechanical behaviour in order to obtain fundamental information that can be used for matrix design. The mechanical properties of the mortar matrix according to the type and content of fine aggregates are investigated. The results reveal that the use of sand with a smaller diameter or a smaller sand–cement ratio can reduce the fracture toughness without significant reduction of the compressive strength and the elastic modulus.

Effect of fiber geometry and tenacity on the mechanical properties of fine aggregates concrete

The effect of fiber cement interactions and its influence on flexural and tensile properties of cementitious composites are well known. In this research, acrylic fibers with different cross sectional and longitudinal shapes and different tensile strengths were selected as reinforcement of the specific fine aggregates concrete. Three point bending test, pullout test, and scanning electron microscopy were used to investigate flexural and pullout behavior of the composites. It was found that flexural toughness and pullout strength were increased 20% and 34%, respectively, by application of kidney shaped acrylic fibers in comparison to dog bone shaped acrylic fibers. It was also found that the flexural and pullout strength of composites containing non-crimped fibers are 33% and 26.5% higher than specimens with crimped fibers, respectively. Results showed that the flexural toughness and pullout strength of high tenacity fiber is 75% and 131% higher than regular fiber as well, respectively. The effect of fine aggregates on the adhesion of fibers to cement matrix was evaluated.

Effect of Fine Aggregate on Properties of Asphalt Mixture

The fine aggregate plays a vital role in the performances of asphalt mixture. In this paper, four kinds of fine aggregates with different lithology, apparent density and water absorption rate were discussed. Asphalt mixture according to AC-13 is prepared by these four kinds of fine aggregates and the volumetric properties, water stability performance and high temperature performance of asphalt mixture were tested. Research shows that: the aggregate performance and the performance of mixture have obvious corresponding relation, which provides the theoretical basis for the engineering application of composite aggregates.

Fine aggregate interference on the performance of asphalt mixtures

Marshall compaction tests of 24 gradations were carried out to study the fine aggregate (2.36 mm and 1.18 mm) interference tendency of volume parameters. An interference coefficient was proposed to analyze the interference rule of different parameters. Then, split test (15°C) was used to measure the tensile property of different mixtures, a comparative analysis of the flow number test (55°C) and rutting test (60°C) was conducted to evaluate the high temperature pavement performance, and the low-temperature property was distinguished by the strain energy density of bending test (0°C, −20°C). The results reveal that the interference effect of fine aggregates (2.36 mm and 1.18 mm) is proportional to the size of an interference particle and the content of coarse aggregates, and is inversely proportional to the nominal maximum aggregate size.

Laboratory Investigate of the Effect of Fine Aggregates on Asphalt Mixture Materials

The objective of this study is to investigate and evaluate the effect of fine aggregates (aggregate size smaller than or equal to 2.36 mm) on the compressive strength and creep behavior of asphalt mixtures. The variables that are considered in the study include the sizes and gradations of fine aggregate. A kind of standant aggregate gradation and four kinds of reduced aggregate gradation mixture specimens are used. Uniaxial compression and static creep tests were realized at different loading conditions. The test results showed that the different fine aggregate sizes do not result in significant differences in compressive strength and creep values using the same percentage of fine aggregates (38.4%). Only the different gradations showed a little differences for mixtures made with different gradations but same aggregate size (between 2.36 and 1.18 mm).

Effects of fine aggregate on the properties of calcium phosphate cements

The effects of the presence of carbonate and calcium phosphate aggregate on the mechanical properties of calcium phosphate cements were explored. Calcium phosphate precursors reacted to form hydroxyapatite at the binder phase. The effects on mechanical properties correlated with the quality of the interfacial bond developed. CaCO3 and 3CaO.P2O5 aggregates are not inert when constituted with calcium phosphate cement and are consumed with time. Mechanical properties and paste microstructure also showed a dependence on the composition of the mixing solution. NaHCO3 dissolved in the mixing solution reacts to form a carbonated hydroxyapatite and this resulted in changes in both compressive strength and morphology.