scholarly journals Influence of Coal Ash on Dense Bituminous Macadam

In the present study, dense graded bituminous mix specimens are prepared using natural aggregate as coarse aggregates, bottom ash as fine aggregates and coal ash as filler. Proportion of aggregate for dense graded bituminous macadam (DBM) grading has been considered as per MORTH (2013) having nominal maximum aggregates size (NMAS) 26.5 mm. The bitumen used is VG20. Firstly, bottom ash and fly ash was used as fine replacement in DBM mix. In this, the total coal ash content is taken as 35% by weight of the total mix, from which the percentage of fly ash as mineral filler is fixed, i.e. 5% of weight of the mix. The bottom ash content is varied according to the DBM gradation specified in MORTH (2013). Detailed study with Marshall test results were used to determine the Marshall characteristics, optimum binder content and also optimum use of coal ash. The maximum stability value of 11.826 kN was achieved when 14% of coal ash by weight of the mix was mixed for preparing DBM samples. It is finally observed that results are not only satisfactory, but also much improved engineering properties with coal ash as fine aggregate and filler. Utilization of non-conventional aggregate like coal ash may help to find a new way of bituminous pavement construction.

1988 ◽  
Vol 25 (4) ◽  
pp. 694-704 ◽  
Author(s):  
P. S. Toth ◽  
H. T. Chan ◽  
C. B. Cragg

Fly ash and bottom ash obtained from coal-fired electric power generating stations can be used as alternatives to natural materials for the construction of structural fills. The engineering properties of coal ash pertinent to its use in structural fills are discussed. Four case studies of coal ash structural fills are presented. The performance of these fills was monitored during and after construction. These cases demonstrate that the physical behavior of fly ash is similar to that of silt and that it can be handled with similar methods. Groundwater monitoring data from existing fly ash fills are presented to show the impact that ash leachate migrating into the groundwater regime has on water quality. Results of long-term corrosion studies are presented to show that metals buried in ash, used in such structures as culverts, cable ducts, guard rails and streetlights, are not adversely affected. Ash leachate was found not to be detrimental to good-quality concrete structures. Key words: fly ash, fill, compaction, leachate, corrosion, concrete.


2021 ◽  
Vol 321 ◽  
pp. 65-71
Author(s):  
Hoc Thang Nguyen ◽  
Phong Thanh Dang

Climate change is recognized as a global problem and even the industrial and construction sectors are trying to reduce the green-house gas emissions, especially on CO2 emissions. In Vietnam, the coal-fired thermal power plants are discharging millions of tons of CO2 and coal ash annually. This coal ash is comprised of about 80% of fly ash and the rest is bottom ash. This study would like to introduce one of the potential solutions in a carbon-constrained society that would not only manage the fly ash but also utilized this as raw material for green materials through geopolymerization. The geopolymer-based material has lower energy consumption, minimal CO2 emissions and lower production cost as it valorizes industrial waste. The fly ash containing high alumino-silicate resources from a coal-fired power plant in Vietnam was mixed with sodium silicate and sodium hydroxide solutions to obtain the geopolymeric pastes. The pastes were molded in 10x10x20cm molds and then cured at room temperature for 28 days. The 28-day geopolymer specimens were carried out to test for engineering properties such as compressive strength (MPa), volumetric weight (kg/m3), and water absorption (kg/m3). The microstructure analysis was also conducted for this eco-friendly materials using X ray diffraction (XRD), and Fourier Transform Infrared Spectroscopy (FTIR), Scanning Electron Microscope (SEM), Differential Thermal Analysis - Thermal Gravimetric Analysis (DTA-TGA).


2015 ◽  
Vol 2015 ◽  
pp. 1-5 ◽  
Author(s):  
Hassan Ziari ◽  
Shams Nowbakht ◽  
Sajad Rezaei ◽  
Arash Mahboob

There are many steel-manufacturing factories in Iran. All of their byproducts, steel slag, are dumped randomly in open areas, causing many environmentally hazardous problems. This research is intended to study the effectiveness of using steel slag aggregate (SSA) in improving the engineering properties, especially fatigue life of Asphalt Concrete (AC) produced with steel slag. The research started by evaluating the physical properties of the steel slag aggregate. Then the 13 types of mixes which contain steel slag in portion of fine aggregates or in portion of coarse aggregates or in all portions of aggregates were tested. The effectiveness of the SSA was judged by the improvement in Marshall stability, indirect tensile strength, resilient modulus, and fatigue life of the AC samples. It was found that replacing the 50% of the limestone coarse or fine aggregate by SSA improved the mechanical properties of the AC mixes.


Author(s):  
D. R. Sasirekha ◽  
S. Thejaswini

In present condition to full-fill the demand of sustainable construction, concrete made with different materials is the best choice for the construction industry. Generally, we use materials which are required for conventional concrete and addition to those we replace the low-cost materials such as bottom ash in this project we replace the coal bottom ash & quarry dust to the fine aggregate by variable percentages. Coal bottom ash is the by-product of coal combustion. The rock detritus filled in the fishers of coal become separator from the coal during pulverization. In the furnace, carbon, other combustible matter burns, & the non-combustible matter result in coal ash. The coal ash collector from the electro static precipitators is called fly ash. coal bottom ash constitutes about 20% of coal ash and the result is fly ash. The perfect substitute for reverse sand is quarry dust it is the one of the ingredients in manufacture of concrete the crusher dust is known as quarry dust can be used as alternative material to the river sand. quarry dust possesses similar properties as that of river sand, hence accepted as a building material. The aggregate replaced with concrete in various percentages as both BA and QD (10%,20%&30%). All replacements where done to the m30 grade of concrete. the concrete has been replaced by coal bottom ash accordingly to the percentage, and fine aggregate has been replaced by quarry dust in percentage. concrete mixtures where produced, tested & compared in terms of compressive strength, tensile, flexural strength are evaluated. The curing of cubes, cylinders, & beams is 7days 28days & 90days.


2018 ◽  
Vol 17 (1) ◽  
Author(s):  
Tumingan Tumingan ◽  
Salma Alwi ◽  
Rafian Tistro

ABSTRACTPond ash is a mixture of fly ash, bottom ash and other ash materials in a pond/lake/beach, pond ash materials are very overload and become waste, so the research of coal ash waste (pond ash) as a substitute of fine aggregate (sand) to increase the compressive strength of concrete influence of time function , were examined using cylindrical specimens of 100 mm diameter and 200 mm height. The specimens were made by taking a percentage ratio of pond ash by 0%: 5%: 10%: 15% and 20% in the mixture with a constant water cement ratio 0.49 based on the results of a normal concrete mix of f’c 25 MPa. The result of analysis of compressive strength to the time function obtained value at the age of 1 day the calculation results do not deviate from the equity line position, after the age of 3 and 7 days. The compressive strength test of concrete resulted in the value of over estimate means that the value of the test result is lower than the result of the equation can be stated that the hardening process of the concrete press is slow, while the age of 14, 28 days and so on the contrary is the result of compressive strength below the equity line or under estimate means the result value the test is higher than the result of the equation so that it can be stated that the process of hardening presses the concrete faster.Keywords: Coal Ash, Pond Ash, Compression strength concrete, time function.ABSTRAKPond ash adalah campuran bahan fly ash, bottom ash dan abu lainnya dalam sebuah kolam, bahan pond ash sangat melimpah dan menjadi limbah, maka di teliti pengaruh bahan limbah abu batubara (pond ash) sebagai pengganti sebagian agregat halus (pasir) terhadap peningkatan kuat tekan beton pengaruh fungsi waktu, diteliti menggunakan spesimen berbentuk silinder diameter 100 mm dan tinggi 200 mm. Spesimen dibuat dengan mengambil perbandingan prosentase pond ash sebesar 0%: 5%: 10%: 15% dan 20% terhadap campuran dengan faktor air semen konstan 0,49 berdasarkan rancangan campuran beton normal f’c 25 MPa. Hasil analisa pengujian kuat tekan terhadap fungsi waktu diperoleh nilai pada umur 1 hari hasil perhitungan tidak menyimpang dari posisi garis ekuitas, setelah umur 3 dan 7 hari, hasil perhitungan kuat tekan menghasilkan nilai over estimate berarti nilai hasil pengujian lebih rendah dari hasil persamaan dapat dinyatakan bahwa proses pengerasan kaut tekan beton lambat, sedangkan umur 14, 28 hari dan seterusnya terjadi sebaliknya yaitu menghasilkan kuat tekan dibawah garis ekuitas atau under estimate berarti nilai hasil pengujian lebih tinggi dari hasil persamaan sehingga dapat dinyatakan bahwa proses pengerasan kaut tekan beton semakin cepat.Kata Kunci : Abu Batubara, Pond ash, Kuat tekan Beton, fungsi waktu


Author(s):  
Najib Nicolas Gerges ◽  
Camille Amine Issa ◽  
Samer Ahmad Fawaz ◽  
Jacques Jabbour ◽  
Johnny Jreige ◽  
...  

Conventional concrete aggregate consists of sand (fine aggregate) and various sizes and shapes of gravel or stones (coarse aggregate). However, there is a growing interest in substituting alternative aggregate materials, largely as a potential use for recycled materials. While there is significant research on many different materials for aggregate substitutes such as granulated coal ash, blast furnace slag or various solid wastes including fiberglass waste materials, granulated plastics, paper and wood products or wastes, sintered sludge pellets and others. Recycled waste glasses were used as coarse and fine aggregates replacement in concrete.  Coarse aggregates were replaced with Green Bottles coarse aggregates at third, half, two thirds, and 100% replacement ratios. The replacement of a third coarse aggregate was established as being the most suitable for retaining the properties of the concrete mix design. As for fine aggregates, in order to account for the numbers of variables and clearly establish a bench mark, the sand grading, color of glass, source of waste glass (bottles and non-bottles), and design mix strength were used as parameters. Fine aggregates from green, brown, and transparent bottles in addition to clear window waste glass were used. Concrete properties were tested in fresh and hardened states. The incorporation of glass sand regardless of the ratios of replacement showed no significant influence on fresh or mechanical properties of concrete except for the case of transparent bottles. Transparent bottles due to the wide source of obtainability have introduced a non-uniform factor that caused discrepancy compared to the rest of the group.


J ◽  
2021 ◽  
Vol 4 (3) ◽  
pp. 223-232
Author(s):  
Esperanza Menéndez ◽  
Cristina Argiz ◽  
Miguel Ángel Sanjuán

Ground coal bottom ash is considered a novel material when used in common cement production as a blended cement. This new application must be evaluated by means of the study of its pozzolanic properties. Coal bottom ash, in some countries, is being used as a replacement for natural sand, but in some others, it is disposed of in a landfill, leading thus to environmental problems. The pozzolanic properties of ground coal bottom ash and coal fly ash cements were investigated in order to assess their pozzolanic performance. Proportions of coal fly ash and ground coal bottom ash in the mixes were 100:0, 90:10, 80:20, 50:50, 0:100. Next, multicomponent cements were formulated using 10%, 25% or 35% of ashes. In general, the pozzolanic performance of the ground coal bottom ash is quite similar to that of the coal fly ash. As expected, the pozzolanic reaction of both of them proceeds slowly at early ages, but the reaction rate increases over time. Ground coal bottom ash is a promising novel material with pozzolanic properties which are comparable to that of coal fly ashes. Then, coal bottom ash subjected to an adequate mechanical grinding is suitable to be used to produce common coal-ash cements.


2016 ◽  
Vol 857 ◽  
pp. 400-404
Author(s):  
Tian Yu Xie ◽  
Togay Ozbakkaloglu

This paper presents the results of an experimental study on the behavior of fly ash-, bottom ash-, and blended fly and bottom ash-based geopolymer concrete (GPC) cured at ambient temperature. Four bathes of GPC were manufactured to investigate the influence of the fly ash-to-bottom ash mass ratio on the microstructure, compressive strength and elastic modulus of GPC. All the results indicate that the mass ratio of fly ash-to-bottom ash significantly affects the microstructure and mechanical properties of GPCs


Author(s):  
Velumani M ◽  
Sakthivel S ◽  
Yuvaraj K

The main aim of the environmental protection agencies and the government are to seek ways and means to minimize the problems of disposal and health hazards of by products. It is considered as a waste material which could have a promising future in construction industry as substitute of either cement or coarse aggregates or fine aggregates. Copper slag is one of the replacement mechanisms of material in concrete. Use of copper slag as a replacement for fine aggregate in concrete cubes various strength measurements was experimentally investigated in this study. Mainly contents of that M35 conventional concrete and copper slag as a replacement of fine aggregate  in 10%, 20%, 30%, 40%,50%, 60%, 80%, and 100% and also Portland Pozzolana Cement is noted. In this regard, laboratory study including water absorption test, bond strength, and percentage of voids, compressive strength & bulk density were conducted in ppc cement concrete which made by copper slag waste as a replacement of fine aggregate and PPC. A substitution up to 40-50% as a copper slag as a sand replacement yielded comparable strength to that of the conventional concrete. However, addition of more copper slag resulted in strength reduction due to the increase in the free water content in the mix, cured period in a curing tank for later resulting at 28 and 60 days.


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