The purpose of this research is to separate different morphological particles of ASTM class F fly ash, and study their effect on mechanical behaviour and durability of high volume cementitious mixtures. In this research wet separation of raw fly ash is carried out, which resulted in three layers of different morphological particles. The first layer of particles float, comprise of about 1-5% of fly ash, is identified as cenospheres or hollow spheres. The second layer of particles is measured to be 55-60% of raw fly ash and consisting of porous spherical and rounded particles rich in Si and Al. The third layer particles is measured to be about 35-40% of raw fly ash. High volume fly ash cementitious composites containing second or third layer particles are tested under compression and bending, highlighting a higher strength and ductility in comparison to cementitious ones containing raw fly ash particles.

This article focuses on comparison between Manual/Traditional and Building Information Modelling (BIM) software based approaches for cost comparison. Centre line method for manual and Revit software for BIM based approaches are used in this research. The principal objectives of this research are to calculate quantities by Manual Centre line method, then to make the cost estimation fast, accurate, efficient, and errorless by using BIM software Rivet, and finally the comparison study of manual based and BIM / Software based estimation. For manual approach, quantities are calculated by multiplying the measurements of length, breadth, and height. Then to get the total quantities the deduction is subtracted from the quantities and final BOQ is prepared for which estimated cost of building is calculated. For BIM based approach, 3D model from 2D floor plan of building is prepared in Revit software, then to estimate the cost of building structure elements, sheets of quantities are generated in the schedule option of the view tab in the software. The Percentage difference between Manual and BIM / Revit Software estimation in brick work, RCC Slab, Plaster Work, PCC for Flooring, Floor Tile Work, Skirting, Paint Work, False Ceiling, Doors and Aluminum Work is 4.57, 2.61, 7.58, 3.27, 1.87, 6.73, 8.03, 1.87, and 0.00% respectively. The total cost difference between manual and BIM based estimation approach comes out to be 4.8%. It is thus concluded that the BIM-assisted estimates have better performance over traditional/manual estimating methods.

Abstract. The properties of fly ashes vary because of the differences in the properties of their individual particles, and the determination of variation in these properties is of interest to the industries which use pulverized raw fly ash in applications, such as in cementitious materials and in the recovery of certain rare elements from raw fly ash. To investigate the differences in individual particles, four pulverized raw fly ashes from thermal power plants of the Czech Republic were used in this research. It was observed from FE-SEM that all four fly ashes consist of glassy hollow spherical, solid spherical, porous spherical, bright spherical, porous slaggy and compact slaggy particles. Box and whisker diagrams were plotted from the data of EDX individual particle analyses, which showed that the data of percentages for the Si, Al, and Fe elements is more scattered as compared to other elements. It was further observed from ternary phase diagrams and pseudo coloured images, that nature of fly ash particles changes from alumino silicate glassy to alumino silicate calcite metallic to pure ferro-metallic, where glassy particles showed high percentages and pure calcite particles were absent in fly ashes. Furthermore, a comparison between the XRF, the EDX total area analyses, showed that the EDX individual particle analysis gives more realistic and reliable data with median, mean, and the standard deviation for percentages of each element present in the fly ashes.

The dry separation of brown coal fly ash was carried out in this research using ultrafine air classifier. Classifiers wheel speed was increased from 2000 to 10000 rpm to obtain fine and coarse products. As the speed of classifier was increased diameter of particles decreased and particle morphology was observed on optical, electron microscopes which showed that at 10000 rpm classifiers wheel speed, average fine particles morphology changed from angular and rounded irregular slaggy particles to spherical particles. High volume cementitious mixes were prepared with fine and coarse products in which cement -60% fine products samples showed a considerable increase of compressive strength as compared to cementitious raw fly ash control samples.

In this research high speed milling was carried out on particles of brown coal raw fly ash, on second layer, and on third layer particles obtained from wet separation of brown coal raw fly ash. Due to milling process, median particle size d50 of raw fly ash, second layer, and third layer reduced by 46 %, 23 %, and 77 %, densities reduced by 11 %, 17 %, and 8 % respectively. Due to milling process, formation of agglomerations was observed, the standard deviation of the chemical composition of each element from the mean value reduced. After milling, high volume cementitious paste mixes were prepared with 60 % cement replacement. Due to the milling process the increase in compressive strength at 28 and 90 days was observed for raw fly ash is 59 % and 16 %, for second layer is 12 % and 15 %, for third layer and milled third layer is 78 % and 75 %. Flexural strength testing showed that due to the milling process the deflections at maximum loads have reduced considerably leading to brittle behavior of milled cementitious specimens. The testing for Mercury Intrusion Porosimetry showed that the cementitious specimens of third layer have maximum concentration of large capillary pores between 0.05 and 10 µm, whereas, all others have maximum concentration of medium capillary pores between 0.01 and 0.05 µm. Autogenous shrinkage of cementitious specimens was measured for first sixteen hours after mixing which showed that the second layer particles have the least shrinkage as compared to all other specimens.