Abrasion Value Research Articles

Mechanical Properties of Crumb Rubber and Basalt Fiber Composite Modified Porous Asphalt Concrete with Steel Slag as Aggregate.

This paper studies the mechanical properties of porous asphalt concrete with styrene-butadiene-styrene (SBS) polymer modified bitumen as the binder, steel slag as the aggregate and crumb rubber and basalt fiber as modifiers. First, the appearance, mechanics, chemical composition and high-temperature stability of steel slag were studied by some equipment. Then, three kinds of porous asphalt concrete with SBS polymer modified bitumen as binder were produced, Namely, crumb rubber modified porous asphalt concrete (CR-PAC), basalt fiber modified porous asphalt concrete (BF-PAC), and basalt fiber and crumb rubber composite modified asphalt concrete (CM-PAC). Finally, the properties of the three kinds of modified PACs were studied through the Marshall test, freeze-thaw splitting test, low-temperature splitting test, permeability test, and creep test. The results showed that the crush value and abrasion value of steel slag are 15.1% and 13.5%, respectively; it has excellent strength and abrasion. In addition, the steel slag shows a porous structure and it provides an interface basis for a better bond with bitumen. For the three PACs, the results showed that the Marshall stability, water stability, and low-temperature crack resistance of CM-PAC are all the best Furthermore, CM-PAC has better rutting resistance than two single modified PACs, based on creep test results. The CM-PAC in this study can be used as a new type of pavement material.

Factors Identification and Conformance of Quality of Cement and Coarse Aggregate used at Gautama Buddha Airport Upgrading Component, Nepal

Quality management system has been challenging in construction of airport project. The objective of study is to assess the factors affecting quality and conformance of Cement and Coarse Aggregate standard used at Construction Site of Gautam Buddha Airport Upgrading Component. This research is based on key informant interview with supervisor and site engineers, questionnaires survey with clients, consultants and contractors who were involved in airport construction projects along with lab test of cement and coarse aggregate of airport construction sites. Statistical tools mean value and relative importance index were used for the ranking of different quality methods. Airport follows specification and standard technical guidelines for the airport construction work. The major factors affecting the quality management in airport construction was Unavailability of competent staff, Low quality drawing and specification and Poor-quality procedure and department for ensuring quality assurance practice Provide training and seminar on quality assurance and Support the setting up of of cube of 3 days, 7 days and 28days is18.8N/mm2 (>16N/mm2), 27.20N/mm2 (>22N/mm2) and 39.40N/mm2 (>33N/mm2) respectively. The average initial setting Time and final setting time of cement is 180 min(>45min) and 351 min(<600min) respectively and average soundness of cement is 2.7mm(<10mm). The test for aggregate, it was found that average Los Angeles Abrasion value of aggregate was 32.8%(<40%), average crushing value of aggregate was 19.88%(<25%), Flakiness index of aggregate found that 19.85%(<25%) and the gradation of aggregate was found that within specification. Quality in airport construction starts from selection of material, inspection, tests employed.

Factors Identification and Conformance of Quality of Cement and Coarse Aggregate used at Gautama Buddha Airport Upgrading Component, Nepal

Quality management system has been challenging in construction of airport project. The objective of study is to assess the factors affecting quality and conformance of Cement and Coarse Aggregate standard used at Construction Site of Gautam Buddha Airport Upgrading Component. This research is based on key informant interview with supervisor and site engineers, questionnaires survey with clients, consultants and contractors who were involved in airport construction projects along with lab test of cement and coarse aggregate of airport construction sites. Statistical tools mean value and relative importance index were used for the ranking of different quality methods. Airport follows specification and standard technical guidelines for the airport construction work. The major factors affecting the quality management in airport construction was Unavailability of competent staff, Low quality drawing and specification and Poor-quality procedure and department for ensuring quality assurance practice Provide training and seminar on quality assurance and Support the setting up of quality assurance department in construction firms. It was found that average Compressive strength of cube of 3 days, 7 days and 28days is18.8N/mm2(>16N/mm2), 27.20N/mm2(>22N/mm2) and 39.40N/mm2(>33N/mm2) respectively. The average initial setting Time and final setting time of cement is 180 min(>45min) and 351 min(<600min) respectively and average soundness of cement is 2.7mm(<10mm). The test for aggregate, it was found that average Los Angeles Abrasion value of aggregate was 32.8%(<40%), average crushing value of aggregate was 19.88%(<25%), Flakiness index of aggregate found that 19.85%(<25%) and the gradation of aggregate was found that within specification. Quality in airport construction starts from selection of material, inspection, tests employed.

Dentin Abrasivity and Cleaning Efficacy of Novel/Alternative Toothpastes.

To investigate dentin abrasivity and cleaning efficacy of novel/alternative toothpastes containing diamond particles, active carbon, sea salt or organic oils. Seventy-two bovine dentin samples (for measuring abrasivity) and 60 human dentin samples (for assessing cleaning efficacy) were used in this study. Samples were divided into six groups as follows: group 1: Elmex Kariesschutz (hydrated silica); group 2: Lavera Neutral Zahngel (sea salt); group 3: Curaprox Black is White (active carbon); group 4: Swiss Smile Diamond Glow (diamond powder); group 5: Ringana Fresh Tooth Oil (hydrated silica); and group 6: artificial saliva. Samples were brushed for a total of 26 min at 120 strokes/min, replacing slurries (1 part respective toothpaste and 2 parts artificial saliva) every 2 min. Finally, abrasive dentin wear was measured profilometrically and cleaning efficacy planimetrically. The highest abrasivity values were observed for Lavera Neutral Zahngel (sea salt 9.2 µm) and Elmex Kariesschutz group (hydrated silica 6.0 µm). The lowest abrasivity value was observed for Ringana Fresh Tooth Oil group (hydrated silica 1.3 µm). The highest cleaning efficacy was observed for Elmex Kariesschutz group (86.7%) and the lowest cleaning efficacy was observed for Ringana Fresh Tooth Oil group (31.3%). The addition of diamond powder or active carbon to toothpastes could offer high cleaning efficacy with low dentin abrasivity. The addition of sea salt to traditional abrasives might cause high abrasive dentin wear without adding further cleaning benefit.

RDA and REA Values of Commercially Available Toothpastes Utilising Diamond Powder and Traditional Abrasives.

To investigate whether toothpastes with diamond powder vs those with traditional abrasives abrade dentin and enamel differently and to determine the relative dentin abrasivity (RDA) and relative enamel abrasivity (REA) values of those toothpastes. Dentin and enamel samples of bovine permanent incisors were randomly allocated into groups of eight, brushed with 20 different toothpastes (three of which contained diamond powder) and analysed for their RDA and REA values. Toothpastes with diamond powder exhibit low RDA values but high REA values. Some RDA values exceeded the ones declared by the manufacturer. Diamond powder as an abrasive might have a mild action on dentin, but it is highly abrasive on enamel.

Evaluating the Abrasivity of a Nanosized Eggshell-Titanium Dioxide on Tooth Enamel Using Atomic Force Microscopy.

Objectives This study aimed to evaluate nanosized eggshell–titanium dioxide (EB@TiO 2 ) abrasiveness in comparison with calcium carbonate and hydrated silica-containing toothpaste. Material and Methods Thirty-five bovine tooth enamels were prepared, and specimens randomly assigned to a sample group of five ( n = 7), namely, Colgate regular, Colgate pro-relief, Sensodyne rapid relief, Sensodyne repair, and EB@TiO 2 . Half of the enamel surface was brushed with each respective sample group, while the other half was covered with a tap. Statistical Analysis The mean roughness value (Ra) of the brushed and covered halves were measured using an atomic force microscope (AFM). To assess the surface morphology and changes, a scanning electron microscope (SEM) was performed. Using pair sample test and ANOVA, the Ra for the entire specimens were analyzed. A Bonferroni correction was used to identify the mean differences among the five groups (α=.05). Results The findings from this analysis show that all the tested toothpaste abraded the enamel significantly ( p < 0.05). The abrasive value contained in toothpaste comprising calcium carbonate was lower than the silica toothpaste hydrated. Conclusion Overall, Colgate regular had the lowest toothpaste abrasivity, followed by EB@TiO2, while Sensodyne rapid relief had the most enamel wear. The prominent feature of this study suggests that EB@TiO2 is suitable for oral use, as its abrasivity is comparable with calcium carbonate-containing toothpaste.

Microstructure characterisation and performance investigation of a rapid hardening emulsified asphalt seal mixture

In terms of longer hardening time of emulsified asphalt seal mixture, a rapid hardening seal mixture was prepared by adding cement and carbon fibre to the Styrene–Butadiene-Rubber (SBR)-modified emulsified asphalt. The mix proportion of mixture was determined by testing the mixable time, consistency, wet track abrasion value, adhered sand content, cohesion force and the cracking rate. The microscopic mechanisms of rapid hardening and cracking control were studied using the Scanning Electron Microscopy (SEM) and the Fourier Transform Infrared Spectroscopy (FTIR). It is found that the optimum contents of SBR-modified emulsified asphalt, added water, cement and carbon fibre in the prepared mixture are 12%, 13%, 4% and 4%, respectively. At 20°C, with a relative humidity of 90% and a wind speed of 10 km/h, the opening time to traffic of mixture adding 4% ordinary Portland cement can be 2 h earlier than that without cement.

High performance cementless composites from alkali activated GGBFS

Some of the thermally activated minerals and pozzolans were generally preferred in the production of geopolymer and/or alkali-activated composites as unary, binary, and ternary mixtures. The general trend is to use Ground Granulated Blast Furnace Slag (GGBFS) as binary or ternary mixes in the production of alkali-activated composites. However, GGBFSs have preferred the only binder in this study. Alkali-Activated Concrete (AAC) specimens were produced by using sodium hydroxide and sodium silicate aqueous solutions in three different molarity values (8, 10, and 12 M) for the formation of activation. For each mixture, three different activation temperatures, 25 °C (ambient temperature), 60 °C and 90 °C for 18 h, were applied. After this process, the specimens were kept under laboratory conditions (25 ± 2.5 °C) for 90 days to gain strength. Then capillary water absorption, density, Dynamic Modulus of Elasticity (DMoE), compressive strength, splitting tensile strength, and abrasion resistance tests were performed on the specimens. Furthermore, microstructure analyses were performed on the selected specimens. In the conclusion, AAC production was able to achieve using 100% GGBFS. High strength cementless concretes with a compressive strength of 82.32 MPa could be obtained by using GGBFS, which is a waste material. Besides, AAC with an abrasion value of 3.86% by weight was obtained in the specimen coded M12T60.

Comparative Study of Physical and Mechanical Properties of Machine and Manually Crushed Brick Aggregate Concrete

With technological advancement on the rise, manual crushing of bricks is gradually being replaced by machine crushing to obtain coarse aggregates for construction. However, properties of the brick aggregates obtained from these two methods vary which in turn, may affect the properties of the concrete matrix as well. This study represents a comparison between the machine crushed and manually crushed brick aggregates to be used as coarse aggregates in preparation of concrete. Four types of bricks, namely first class, second class, picket (over burnt) and ceramic were investigated, and each was crushed both manually and mechanically to a usable form of aggregates. The physical and mechanical properties of the brick aggregates derived from the two methods were tested and compared. In all types of brick, aggregates size, shape and strength properties such as flakiness and elongation indices, aggregate impact and crushing values and Los Angeles abrasion value showed lower values for manually crushed aggregate indicating better properties compare to machine crushed aggregates. This was evident while comparing compressive and tensile strength of concrete prepared with both manually and machine crushed first class and picket brick aggregates. Concrete with manually crushed brick aggregates showed marginally higher compressive and tensile strength in both types of brick aggregates.

Experimental investigations on potential of brick-based building-derived materials for geotechnical applications

A large quantity of solid waste, known as construction and demolition waste (CDW), are being generated by the construction activities and its associated demolition practices. Huge proportion of CDW is comprised of building-derived materials (BDM) that come from the demolition of buildings which include brick and concrete—based elements. The present study was aimed at characterization of brick-based building-derived materials (BBDM) to encourage by reusing and recycling them in practical purposes. Currently, BDM find its application as recycled aggregates, and extraction of the antecedent aggregates from virgin BDM by various physical and chemicals processes increases the cost. To address this issue, this study accentuates the use of BDM to provide significant cost reduction, which besides reduces the impact on landfills, preserves natural coarse aggregates and saves energy. BBDM were characterized through a series of physical and microscopic investigations to assess their compatibility for using in combination with local soil and even exposed to a very aggressive chemical environment like acids, salts and seawater to study their response. Grain size analysis, compaction characteristics, water absorption, abrasion and strength tests were performed on locally available sand mixed with 5, 10, 20 and 30% of BBDM by weight in a chemically aggressive environment. Aggregate impact value (AIV) of 41% and Los Angeles (LA) abrasion value of 45.8% indicate that the BBDM are resistant to impact loads and satisfy the prerequisites of a subbase material. The angle of shearing resistance (ϕ) of virgin BBDM is 46°, and it is found to decrease with exposure to the chemicals.

Aggregate Suitability of the Late Permian Wargal Limestone at Kafar Kot Chashma Area, Khisor Range, Pakistan

This study was carried out for the investigation of the Late Permian Wargal limestone at Kafar Kot Chashma area, Khisor Range to determine its suitability as an aggregate that is used in road construction and civil structures with the help of geological engineering testing. The results of geological engineering testing of Wargal limestone samples show the tolerable values of all standard engineering parameters including the Loss Angles Abrasion value (23.37%), Aggregate impact (16.8%), Crushing value 13.1%, Unit weight 1.67, Soundness (1.007%), Specific gravity (2.70), Water Absorption (0.48%), Flakiness Index (6.5%), Elongation value (7.1%), Coating of bitumen (&gt; 95%), stripping of bitumen (&lt;5%), California Bearing Ratio (CBR) value (93.6%), Maximum Dry Density 2.307g/c and Optimum Moisture Content (5.79%). As per different International and National Standards like AASHTO, ASTM, BS and NHA, the mentioned results of various engineering tests were within the tolerable limits. The petrography of the selected samples of the Late Permian Wargal limestone revealed very minor value of quartz (0.5%), hematite/limonite (0.6%) and clay content 1.0% showing the insignificant threat of ASR. The values of dolomite are limited to (1%) which shows that there is no ACR reaction with ordinary Portland cement. The results of geological and engineering parameters of the study area strongly suggest its suitability as a potential aggregate (i.e. for the base course, subbase course, cement concrete and asphalt) in the road construction.

The engineering assessments and potential aggregate analysis of mesozoic carbonates of Kohat Hills Range, KP, Pakistan

China-Pakistan Economic Corridor (CPEC) is the ongoing mega construction project in Pakistan. This project provides multi trading routes like roads, railways and fiber optics to more than 70 countries. Additionally, local infrastructure and industrial zones construction in Pakistan is also the part of this project. This construction needs a considerable amount of construction materials. Therefore, the Mesozoic carbonates were studied in the vicinity of Kohat Hills Range, Khyber Pakhtunkhwa province, Pakistan, for the fundamental engineering assessments. The Mesozoic carbonates are extensively exposed in Kohat Hills Range. The petrographic observations reveal that these carbonates are dominantly composed of limestone with subordinate dolomites. The limestone is well preserved and not extensively affected by diagenesis, which affects the aggregate capability, and there was not found any deleterious material which can cause alkali–silica reaction and alkali–carbonate reaction. Likewise, the fundamental engineering tests were performed, which shows proper matching with petrographic observation. The specific gravity, water absorption, soundness, los angeles abrasion value, unite weight, impact value, flakiness and elongation, bitumen coating, and crushing values reveal that these aggregates are well according to the specified limits of the international standards AASHTO, ASTM, and BS. Based on the results obtained, the Mesozoic carbonates of the Kohat Hills rang are recommended as potential aggregate resources for megaprojects like CPEC and other ongoing construction projects.

Determination of the relationship between the Los Angeles abrasion values of aggregates and concrete strength using the Response Surface Methodology

The present study aims to determine the relationship between aggregate abrasion strength and concrete strength considering water-to-cement and aggregate-to-cement ratios. For this purpose, concrete mixtures with different water-to-cement ratios (0.38, 0.40, 0.42, 0.45, 0.50, 0.55 and 0.60) were prepared with different aggregate types (basalt, marble, limestone, and natural aggregates). Hardened concrete properties of the prepared specimens were determined. Also, the abrasion tests were performed for each aggregate used in the experiments to determine the Los Angeles abrasion values of the aggregates. Using the experimental data, the compressive strength and splitting tensile strength values of the concrete specimens with dimensionless parameters such as water-to-cement ratio, aggregate-to-cement ratio, and Los Angeles abrasion loss value were analyzed using the Response Surface Methodology. Thus, two new models were developed with a multi-purpose optimization method. The compressive strength and splitting tensile strength can be calculated with high accuracy for different mixture designs with these models using the aggregate abrasion loss value, water-to-cement ratio, and aggregate-to-cement ratio. In conclusion, savings in labor and time, and economic profit are expected by designing a concrete mixture in this way.

Adaptation of Laboratory tests for the assessment of wear resistance of drill-bit inserts for rotary-percussive drilling of hard rocks

The development of wear resistant materials for drill-bit inserts are of primary importance for efficient percussive drilling in hard abrasive rock. To speed up the development of enhanced wear resistance materials, the laboratory tests are fundamental to evaluate the material performance before proceeding to the in-field drilling test which is labor-intensive and costly in time and resources.The current work aims to perform a comparative study of the wear resistances of drill-bit inserts intended for rotary-percussive drilling. Three laboratory testing methods were adapted to evaluate the abrasive sliding wear and abrasive impact wear which are the main wear components in rotary-percussive drilling. The standard abrasion value (AV) test and the standard LCPC (Laboratoire Central des Ponts et Chaussées) test which were originally developed to study the rock abrasivity, are adapted to study, respectively, the abrasive sliding wear and abrasive impact wear of drill-bit inserts. The disintegrator abrasive impact wear test was adapted to study the effect of impact velocity on impact abrasive wear. The testing setups were modified to enable testing drill-bit inserts as specimens. The drill-bit insert materials were selected to represent various cemented carbide microstructures including five WC-Co grades which differ by the volume fraction of Co and the grain size of WC, and one diamond enhanced insert. All drill-bit inserts were tested in dry condition against Kuru grey granite which is a homogenous rock and well suited as a reference in connection with hard rock testing. The wear measurements were evaluated with respect to the effects of drill-bit insert material and microstructure.The abrasive sliding wear test and abrasive impact wear tests exhibit similar behavior related to the effects of average grain size of WC and volume fraction of Co on the wear measurements for the investigated WC-Co inserts. In all performed tests, the weight losses of WC-Co inserts increased with the volume fraction of Co and average grain size of WC. The abrasive impact wear tests performed on diamond enhanced insert showed a significant improvement of the impact wear resistance by adding diamond particles. Though the removal of the composite matrix between diamond particles was observed, the diamonds particles were providing an additional protection for the composite matrix which explain the lower mass losses of diamond enhanced insert compared to WC-Co inserts. However, an initial stage of decohesion at the diamond/WC-metallic binder interface were observed indicating possibilities of diamond removal at more higher impact energy.

The Effect of The Aggregate Abrasion Value on The Aggregate Pore Content in The Base Layer above Base B

Campuran lapisan pondasi bawah base B yang baik mempunyai persyaratan untuk agregat yang digunakan yaitu nilai abrasi kecil dari 40%, nilai berat jenis agregat minimum 2,5 dan penyerapan air agregat maksimum 3%. Hal ini sebagai syarat untuk menghindari degradasi dan disintegrasi agregat serta penyerapan air yang baik pada saat pencampuran, penghamparan, pemadatan maupun pada saat melayani lalu lintas selama umur rencana. Penelitian bertujuan untuk mengetahui pengaruh nilai abrasi terhadap nilai penyerapan air rongga pada campuran lapisan pondasi bawah base B dengan menggunakan 3 jenis quarry agregat. Penelitian ini menggunakan alat Los Angeles dan analisa saringan. Berdasarkan hasil pengujian diperoleh nilai abrasi paling baik adalah agregat quarry Solok yaitu 17,5 %, kemudian agregat quarry Pangkalan yaitu 23,7 % dan nilai abrasi yang kurang baik agregat quarry Bangkinang yaitu 34,58. Nilai penyerapan air agregat quarry paling tinggi adalah quarry Bangkinang kemudian quarry Pangkalan, dan nilai penyerapan paling kecil adalah quarry Solok. Hasil dari penelitian ini diharapkan dapat membantu pihak yang berkompeten dalam memberikan rekomendasi penggunaan material berdasarkan nilai abrasi dan nilai penyerapan air agregat.

Characterization of Classified Indian Reclaimed Asphalt Pavement RAP Aggregate Impact Value and Aggregate Abrasion Value of Rap Aggregates

Reuse of existing deteriorated bituminous pavement material in construction and maintenance of flexible pavement is called recycling of bituminous pavement. Removed and reprocessed deteriorated pavement material which is recycled is termed as Reclaimed asphalt pavement (RAP). In India during construction of flexible pavement different types of bituminous layers are in practice depending upon CBR of sub-grade and traffic count i.e. CVPD of the road stretch. Depending upon types of bituminous layer i.e. PC Seal Coat, Bituminous Macadam(BM), Dense grade bituminous Macadam (DBM), Semi Dense Bituminous Concrete (SDBC) or Bituminous Concrete(BC) Reclaimed Asphalt Pavement can classified in different groups These classified RAP groups materials will have different characteristics i.e. Rap aggregates and Recovered bitumen of different group of RAP will have different characteristics. In this study characterization of RAP limited to Aggregate Impact Value (AIV) and Aggregate Abrasion Value (AAV)of RAP aggregates of RAP classified in different groups. Results of this study will be compared to standard value of AIV and AAV required for bituminous construction to predict that RAP aggregates are suitable or not for use in bituminous mixes.

The effect of alkali on the reaction kinetics and strength of blast furnace coke

Coke is the main reductant for iron making in blast furnace. The reactivity and strength of coke play a very important role in selection of coke as reductant in blast furnace. The reactivity and strength of coke are inversely related to each other. It is very important to find a coke with good combination of strength as well as reactivity. Alkali elements present in coke increase the reactivity of coke on one hand while reducing the strength on the other hand. It is very important to study the effect of alkali on coke to understand its behaviour in the blast furnace. This work has been done to find out the effect of alkali elements on the coke reactivity index (CRI), coke strength after reaction (CSR) and the abrasion value (AV) of coke samples. The isothermal kinetic study has been carried out to get a better understanding of the influence of alkali on the reaction mechanism of coke during bouduard reaction.

Characteristic of melted slag from wrought iron industry as green concrete material

Utilization waste material on concrete ingredients or its manufacturing that did not harm the environment is the need for the environment sustainability. It is the background of research in concrete design for more environmental friendly as often called green concrete. This work aims to investigate the usability of the melted slag, obtained from local wrought iron industry, as aggregates replacement according to waste material utilization. In particular, it focused on studying the feasibility of replacing the aggregates using melted slag by investigating the basic physical characteristic. Slag is known have a high percentage of silica and ferric oxides, which gives pozzolanic activities that suitable to use as cement blended product. Slag waste used in this work is obtained from the wrought iron industry from Pakis district, Magelang Regency, Central Java, Indonesia. The slag chunk extracted from the furnace then crushed to smaller particle sizing as fine aggregates and coarse aggregates. The aggregates characteristic is observed in relation to gradation test, specific gravity, bulk density, clay lumps percentage, and Los Angeles abrasion value. All of observation parameters are taken consecutively based on SNI and ASTM specification to evaluate its compatibility as concrete aggregates. The current work remarks that the fine and coarse aggregates generated from wrought iron slag do not reveal complete fulfilment in the aggregate specifications of any standard. Even though, the slag fine aggregates could be used in standard or lightweight concrete with further treatment such as crushing to smaller particle size, washing to minimize the clay lumps, and mixing with natural aggregates.

Investigation on Comparison of Morphological Characteristics of Various Coarse Aggregates before and after Abrasion Test.

Under the repeated loading, the continuous impact and friction of tires on aggregates resulted in some changes in their morphology, which may cause rutting, decrease in skid resistance, and fatigue damage of the road. In order to explore specific changes in coarse aggregate morphology, the Los Angeles abrasion test was used to simulate the force exerted on coarse aggregates and the morphologies of different aggregates before and after abrasion were compared. Four types of coarse aggregates were selected and their mineral compositions were analyzed by X-Ray Diffraction (XRD). The morphological characteristics were measured using Aggregate Image Measurement System (AIMS-Ⅱ), including angularity, surface texture, sphericity and Flat and Elongation (F and E) ratio. Results showed that the angularity value for each type of aggregates significantly reduced after abrasion and the angularity reductions of various aggregates were consistent with the results of abrasion test, indicting the angularity reduction was the main component of abrasion loss. Whereas, there was no significant different between the surface texture of coarse aggregates before and after abrasion. For shape properties, both sphericity and F and E ratio results showed that aggregates with excessively high F and E ratio were easy to break, which might cause rutting and were harmful to pavement. Therefore, for pavements with high performance requirement, coarse aggregates with large angularity and low abrasion value should be preferred, whereas the quantity of particles with excessively high F and E ratio should be controlled.

Enhancing the use of coal-fly ash in coarse aggregates concrete

The experimental work has been made to estimate the operation of coal-fly ash as acceptable and coarse aggregates concrete with the ordinary Portland cement of 53 grade. Initially, the chemical and physical characteristics of coal-fly ash particles, such as chemical compositions, detailed significance and XRD, SEM images have been studied. The effect of acceptable to the coal-fly ash on the movement characteristics of palletisation process have been studied in form of particle and cement absorption of coal-fly ash. Additionally, the experimental is showed by substituting acceptable and is constituents with preparation of cement & Fly ash ratio on 20:80, water binder ratio: 0.3 with effect of experienced at 32 days. The properties of fly ash coarse aggregates (FCA) were experimental studied if only based on the aggregate soundness test, crushing value, impact value, abrasion value and water absorption. The impact value test analysis of their two synthesis like as (i) fly ash coarse aggregate concrete (FAC-100%FCA) (ii) Conventional coarse aggregate (CC-100%CA) and partially replaced fly ash coarse aggregate concrete (PRFAC − 50%CA + 50%FCA) to verified in IS methods of M30 grade and its good fitness of microanalysis. To compare the influence of FACA concrete is exposed to that use of fly ash slightly touches the permanence (Fresh, hardened and durability) properties of conventional concrete.