Ash Concrete Research Articles

Mechanical properties and damage constitutive model of concrete containing waste glass and rice husk ash in high-temperature environments

The application of waste glass and rice husk ash in concrete promotes sustainable development by reducing resource consumption and environmental pollution. This study evaluates the high-temperature performance of concrete containing glass sand, glass powder, and rice husk ash. Results show that waste glass increases mass loss, while rice husk ash reduces it and enhances concrete compactness. At ambient temperature, compressive strength is lower in rice husk ash samples compared to waste glass concrete, but higher at elevated temperatures. Particle size differences between glass sand and glass powder mainly influence high-temperature performance. Waste glass does not significantly mitigate cyclic loading damage, whereas rice husk ash reduces damage in glass sand concrete but not in glass powder concrete. A uniaxial compression thermo-mechanical coupling damage model and an improved Broutman-Hull cyclic compression damage model are established, providing a basis for the design and safety evaluation of concrete structures in high-temperature environments.

A Thermal Study on Foam-Based Eco-friendly Cinder Tiles

This study focusses on usage of fly ash and metakaolin as industrial waste to aerate lightweight foam concrete (LFGC) using hydrogen peroxide. By designing and optimising the components of metakaolin, hydrogen peroxide, and fly ash, physical properties such as mechanical strength, thermal characteristics, and heat resistance are assessed. Lightweight foam concrete has a dry density between 1400 and 1800 kg/m3, a bending strength between 0.7 and 1 MPa, and thermal conductivity between 0.1 and 0.7 W/mK, all of which indicate that it is more lightweight than normal concrete. By dumping solid waste on land, the environment suffers, and it leads to the release of toxic gases into the atmosphere and get polluted. As a byproduct, swapping out the cement with concrete would be a practical and cost-effective way to use the refuse. Alkaline solutions such as NaOH and Na2Sio3 are used to prepare geopolymer concrete. Samples of geopolymer concrete made with fly ash and metakaolin are cured in the oven for 24 hours. Geopolymer concrete is a form of material-based construction in which industrial raw materials supplied by businesses are incorporated into it. This lowers carbon emissions and makes the concrete more environmentally friendly. Using MATLAB, we predict which is the best value of bending strength, thermal conductivity, heat resistance, and dry density of various ash concrete. Effective input variables for geopolymer concrete include the amounts of fly ash, metakaolin, NaOH, and Na2SiO3, Fine aggregate, and the ratio of NaOH and Na2SiO3 and the output variables are bending strength, dry density, thermal conductivity, heat resistance.

A Study on use of Rice Husk Ash in Concrete

A Study on use of Rice Husk Ash in Concrete

Study on use of Rice Husk Ash in Concrete

Study on use of Rice Husk Ash in Concrete

Investigation on Utilization of Medical Waste Ash in Concrete

There is a major problem in India for generation of biomedical waste from health care units, research laboratories, clinics and other medical sources. Generation of waste adversely affect the whole environment for human being. Therefore Utilization of medical waste ash is a challenging work for all over India. Some researches revealed the scope for the use of medical waste ash in concrete as partly replacing of cement. In this paper the study describes the workability, density and compressive strength of concrete after partly replacing of cement with medical waste ash. Keyword: Medical waste, ash, concrete, coarse, aggregate, workability.

Environmental impact evaluation of low-carbon concrete incorporating fly ash and limestone

This work examines the environmental impact of low-carbon concrete that incorporates supplementary cementitious materials (SCMs). After reviewing near-zero carbon SCMs and low-carbon concrete, a life cycle assessment (LCA) was undertaken for concrete mix designs with normal-to-high compressive strengths, incorporating limestone and fly ash as cement replacements. The analysis includes relevant region-specific life cycle inventory parameters for raw materials, energy production, and transportation. A comparative assessment between embodied carbon emissions and the material mechanical performance is then made. The results of this paper indicate that incorporating limestone and fly ash in concrete can reduce carbon emissions, yet at a proportional decrease in mechanical properties compared to conventional cement concrete. The combination of cement and fly ash produced, on average, a higher strength concrete by 20.5% and lower CO2-eq values by 21.1% when compared to limestone cement blends. The CO2-eq emissions associated with transportation of the main constituents for concrete production were on average below 4% of the total CO2-eq per mix. In addition to eco-mechanical quantitative assessments, the study offers insights and recommendations for the development of concrete materials considering global resource availability of near-zero carbon concrete constituents.

Analyzing the Mechanical, Durability, and Microstructural Impact of Partial Cement Replacement with Pumice Powder and Bamboo Leaf Ash in Concrete

This study explores the physiomechanical and durability properties of C-25 concrete by partially replacing cement with blends of pumice powder (PP) and bamboo leaf ash (BLA). The combined amount of major oxides SiO2, Al2O3, and Fe2O3 in PP is 84.59%, while in BLA, it is 74.4%, classifying PP and BLA as class N and F pozzolans. Subsequently, the study examines the impact of different cement replacement percentages, emphasizing 5%, 10%, 15%, and 20% on C-25 with varying mixes of concrete: Mix-1 (100, 0, and 0), Mix-2 (90, 5, and 5), Mix-3 (85, 10, and 5), Mix-4 (85, 5, and 10), and Mix-5 (80, 10, and 10) which correspond to the proportions of OPC, VPP, and BLA used in each mix respectively and by using 1 : 2.34 : 2.68 (cement : sand : aggregate) with the water/cement ratio (w/c) of 0.491. The study’s findings indicate that as the proportion of PP and BLA increases in concrete, the workability of the mixture decreases. Moreover, on the 28th day, Mix-2 with (35.84 MPa) and Mix-3 with (33.55 MPa) met the desired mean compressive strength (33.5 MPa) required for C-25 concrete per the ACI standards. Additionally, the flexural strength of concrete produced with partial replacement of Mix-2 with a flexural strength of 3.86 MPa fulfills the minimum strength requirement of 3.5 MPa specified by the C-25 ACI standards. The PP and BLA blended concrete had lower water absorption than the control mix in Mix-2. It also improved resistance to sulfuric acid attack, and Mix-3 had the least strength reduction of 9.59%. In contrast, the control mix has a 33.34% strength reduction.

OPTIMIZATION OF CONCRETE CONTAINING SAWDUST ASH USING CENTRAL COMPOSITE DESIGN

Concrete admixed with materials with pozzolanic properties helps to reduce micro cracks which is the major problem faced by conventional concrete. Incorporating sawdust ash in concrete helps to produce sustainable and cost effective concrete structures. This investigation focused on partial replacement of cement with sawdust ash in concrete. The physical and chemical properties of sawdust used were extensively explored and characterised. The performance of concrete mixtures was assessed in terms of workability, tensile strength, flexural strength, water absorption. The durability of admixed concrete in acidic and sulphate environment was also assessed. Optimization was carried out using central composite design to generate optimal value and model equations for the responses. The preliminary study showed that sawdust ash had enough silica content which can help in strength development of concrete at later ages. The consistency of cement was 29% and increased with increasing sawdust ash content. From the results of numerical optimization, the optimum tensile strength of 2.69N/mm2 , flexural strength of 7.69 N/mm2 and water absorption of 1.33% were obtained at 10% SDA content and 56 days curing. It was evident that sawdust ash concrete absorbs more water compared to control specimens and also the strength of SDA concretes immersed in sulphate and acidic solutions have 50%MgSO4, 90%HNO3 23%Na2SO4 lower compressive strengths than the control cubes immersed in water only. The research recommends that research should be carried out to evaluate the effects of more supplementary locally available materials in binary and ternary mixture with SDA.

Experimental investigation on utilization of substitute building materials in concrete using neural networks

The replacement of cement with sugarcane bagasse ash in concrete is considered due to its rich properties of projecting pozzolanic activity. The availability of aggregates is becoming scarce as a result of the non-renewable characteristic of fine and coarse aggregates. The construction waste end products like demolishing waste also cause the problem of improper disposal. Hence a majority of the construction industries have preferred the usage of construction and demolition (C&D) waste as a replacement for coarse aggregate. Substitution of coarse aggregates by construction and demolition waste and fine aggregates by iron slag ash is considered. The Taguchi method is adopted for the determination of mix combinations. This paper focuses on determining the properties of concrete having pozzolanic properties by replacing the cement with sugarcane bagasse ash (SBA), coarse aggregate with demolished building waste (DBW), and Fine aggregate with iron slag ash (ISA). The experimental investigation proved that SBA, DBW and ISA have a potential sign to be used as an alternative sustainable building material. From the comparative analysis of experimental results with ANN, it is revealed that the concrete show an acceptable prediction of physical and strength properties.

RESEARCH BEHAVIOUR OF WATER HYACINTH ASH IN CONCRETE WITH A PARTIALLY REPLACED OF CEMENT

RESEARCH BEHAVIOUR OF WATER HYACINTH ASH IN CONCRETE WITH A PARTIALLY REPLACED OF CEMENT

Investigations on Strength and Durability Properties of Recycle Aggregate and Fly Ash in Concrete

In this investigative study the Natural Coarse Aggregate (NCA) were put back with Recycled Course Aggregate (RCA) at peculiar proportions, the mechanical performance and durability properties of concrete are examined. The inclusion of fly ash (FA) is also introduced as stand–in of Cement. The present investigation aims to determine the effect of RCA as an stand-in material to NCA and to analyze the fresh properties like workability, density and hardened properties like Compressive Strength, Flexure Strength, Split Tensile Strength and durability properties like Water permeability and Sorptivity. Mix is formulated for water cement ratio 0.40. The specimens were casted of replacing virgin aggregate with RCA by 10% and 20%, and cement with FA by 10%, 20% and 30%. All the specimens are cured for 7 and 28 days as per requirement later they are tested. The acquired data are then compared between the strength of NCA of concrete and the proportion of RCA and FA. The outcome view is in such a way that the workability of concrete will decline as the replacement of RCA increases, by which it should limited to a fixed percentage (10% or 20%). The density of concrete is not altered by the put back of FA, but raise in percentage of RCA replacement could alter the density of concrete. In case of Compressive, Flexure and Split tensile strength of concrete the optimum strength obtained for 10% FA and 10% RCA for 7 and 28 days was similar to that of 100% NCA and 0% FA and durability studies also gave the optimum results for the same replacement.

Exploring the synergistic effect of fly ash and jute fiber on the fresh, mechanical and non-destructive characteristics of sustainable concrete

The utilization of waste fly ash and natural jute fiber has drawn attention to producing sustainable concrete. However, there is a lack of studies to analyze the synergistic effect of jute fiber and fly ash on the properties of concrete. Hence, the aim of this study is to investigate the combined effect of fly ash concentration and the different sizes of jute fiber on the fresh, hardened, and non-destructive testing properties of concrete. Concerning the purpose, the concrete mixes were prepared with 0.2 % and 0.4 % jute fiber incorporating 0 %, 5 %, 10 %, and 15 % replacement of cement by fly ash in concrete. For the assessment of properties, slump, density, and compacting factor test was conducted at the fresh state of concrete, whereas mechanical properties such as compressive, splitting tensile, and flexure strength test were conducted at 7 and 28 days. In addition, the non-destructive test (NDT) was also carried out to predict the destructive compressive strength by rebound hammer at 28 days. The microstructure property of optimum mix concrete was analyzed by scanning electron microscopy (SEM). It is observed that the incorporation of jute fiber decreased the slump, density, and compacting factor but increased the compressive, splitting tensile, and flexure strength, whereas the fly ash improved both fresh and hardened properties. Compared to the standard mix, fly ash-based JFRC mixtures have compressive strength improvements varying from 1.7 % to 25.9 %. The 10 % fly ash and 0.2 % volume of jute fiber exhibited a maximum of 11.64 % and 10.72 % splitting tensile and flexural strength enhancement at 28 days, respecting the control mix. In addition, the NDT strength assessment obtained 5.5 % less than destructive strength on average. From the SEM point of view, it is obtained that the 10 % fly ash with 0.2 % jute fiber composition matrix exhibits a better bonding interface and the cracking resistance nature of the concrete mix.

PARTIAL REPLACEMENT OF CEMENT WITH FLY ASH IN CONCRETE MIX DESIGN

PARTIAL REPLACEMENT OF CEMENT WITH FLY ASH IN CONCRETE MIX DESIGN

Influence of silane treated nano eggshell powder on mechanical and durability properties of concrete

In order to test concrete’s sustainability, this study substitutes nano eggshell powder (nESP) for cement in a silane-treated environment. The results showed that the silane-treated concrete mixtures outperformed the untreated ones in terms of performance. nESP was replaced by 5 to 20% with in cement of 5% along with constant replacement of 30% fly ash by weight of cement. It was found that partial cement substitution with nESP up to 10% produced a sample with greater strength than the control sample. The filling and reinforcing properties of the nESP and the pozzolanic effect of flyash after silane treatment produced favorable results when mechanical strength was evaluated. The increased electrical resistance with age may be caused by the increased hydration products and excess CSH gel formation induced by the pozzolanic action of the fly ash in concrete.

A Locally Available Natural Pozzolan as a Supplementary Cementitious Material in Portland Cement Concrete

For several decades, class F fly ash has been an attractive supplementary cementitious material, at least in part, due to its ability to reduce Portland cement consumption and mitigate alkali-silica reactions in concrete. However, fly ash availability is becoming uncertain as the energy industry decommissions coal burning power plants as it transitions to renewable energy production. This situation creates a need to identify viable and sustainable alternative supplementary cementitious materials. There are several types of supplementary cementitious materials, such as natural pozzolans, metakaolin, or ground granulated blast-furnace slag, which appear to be potential alternatives to fly ash in concrete. In this research, a locally available natural pozzolan (pumicite) was selected to replace fly ash in concrete. After conducting alkali-silica reaction tests on mortar mixtures, rheological and strength properties, shrinkage, resistance to freezing and thawing, and chloride ion permeability of concrete mixtures containing different amounts of fly ash and natural pozzolan were evaluated. The results showed that pumicite was more effective than fly ash at mitigating the alkali-silica reaction, and a pumicite content of 20% was necessary to mitigate the alkali-silica reaction. Ternary mixtures containing both pumicite and fly ash were the most effective cementitious materials combinations for mitigating the alkali-silica reaction expansion. Additionally, pumicite provided acceptable compressive strength and modulus of rupture values (greater than 4.0 MPa) that exceeded the flexural strengths provided by established mixtures containing only fly ash. Shrinkage and durability factor values for all mixtures were less than 710 μstrain and greater than 75, which are generally considered acceptable. Additionally, all mixtures with acceptable alkali-silica reaction expansions had very low chloride permeability. These results indicate that pumicite can be a reliable alternative for fly ash.

EFFECT OF BORAX ON SETTING TIME OF GEOPOLYMER CONCRETE BASED ON FLY ASH TYPE C

Geopolymer concrete is a new type of concrete that does not use cement as a binder at all. In addition to replacing cement, the use of fly ash in concrete can reduce coal emissions from many coal-fired power plants. However, geopolymer concrete has drawbacks, one of which is that it has a setting time that tends to be too fast. Therefore, this study aims to determine the effect of adding borax on the hardening time and compressive strength of geopolymer concrete. With the addition of 1%, 3%, 5%, and 10% borax. The ratio of activator Na2SiO3 and NaOH is used 2.5:1 with a molarity of 10M NaOH. Variations in the addition of borax during mixing include 1%, 3%, 5% and 10% by weight of fly ash. The test results showed that the higher the borax content added, the longer the setting time. The longest final setting time was achieved in geopolymer concrete with the addition of 10% borax for 480 minutes.

Experimental evaluation of alkali-activated and portland cement-based mortars prepared using waste glass powder in replacement of fly ash

The decreasing trend in coal fly ash production has led to a rapidly growing interest in finding alternative materials to replace fly ash in concrete. In this study, the use of glass powder to replace fly ash in concrete was investigated. The performance of portland cement and alkali-activated slag-based mortars containing fly ash (class F) or glass powder (aluminosilicate-based) was evaluated via a series of experiments, including fresh, physical, mechanical, and restrained cracking tests. Notably, a customized restrained shrinkage test was used to investigate the cracking potential. Results showed that the ultra-fine glass powder performed differently in the two binding systems. In the portland cement system, the use of glass powder yielded higher concrete mechanical performance compared to the concrete containing fly ash, while the opposite conclusion was obtained for the alkali-activated system. Comparing the alkali-activated system with the portland cement system, the alkali-activated materials with either fly ash or glass powder had higher free shrinkage and developed cracks much earlier under the restrained drying shrinkage. However, the alkali-activated materials maintained a high level of strain in the steel ring, which was primarily attributed to the development of multiple cracks and their different bonding at the mortar and steel interface.

Preservation of Natural Resources by Utilizing Combustion Ash in Concrete and Determination of its Engineering Properties

Due to the large amount of combustion ash being thrown into landfills, which can lead to environmental pollution, new alternatives to construction materials can be developed by utilising this combustion ash as a part of the main raw materials, while at th

Compression behavior and permeability of concrete composed of glass sand and rice husk ash

Using glass sand and rice husk ash as raw materials for concrete production can effectively save resources, protect the environment, and promote waste recycling. In this study, glass sand (20%) and rice husk ash (15%, 30%, 45%) are used to replace natural river sand and cement in concrete, respectively, while ordinary concrete is also considered as a reference. The effects of glass sand and rice husk ash on the performance and structural safety of concrete were evaluated through a series of experiments, including slump test, uniaxial compression test, triaxial compression test and dynamic compression test. The experimental results show that glass sand reduces the slump, uniaxial compressive strength, and triaxial compressive strength of the concrete but improves its dynamic compressive strength and strain rate sensitivity. In addition, the permeability of glass sand concrete is observed to be lower than that of ordinary concrete under high confining pressure. Furthermore, when the replacement rate of rice husk ash is 15%, the experimental results are found to be better than those for other mixtures, except for the uniaxial compressive strength. However, increasing the replacement rate to 30% and 45% fails to meet the strength requirements of structural concrete. Moreover, when subjected to external load, the samples containing rice husk ash exhibits toughness and plastic deformation failure characteristics, which became more obvious with an increase in the rice husk ash replacement rate. Overall, this study provides novel insights into the performance of glass sand and rice husk ash in concrete.

Toward effective utilization of fly ash and multi-binder system with fly ash in concrete

This paper describes first the situation of fly ash in various ASEAN countries. Then the development of fly ash utilization in Thailand is discussed, which includes fly ash specification, standards on durability and service life design for fly ash concrete, and in the final, study results of application potential of various off-spec fly ashes are elaborated. Characteristics of fly ash in different ASEAN countries are different and have different problems. Thailand has 2 major sources of fly ash which have significantly different properties, especially CaO content (high and low CaO). Therefore, the standard specification of the Thai fly ashes classifies the fly ashes based on both quality classes (Classes 1, 2, and 3, with class 1 having the highest quality) and CaO content (high and low CaO). The effects of the fly ash were considered in the durability and service life design standard, for example in estimating the diffusion coefficient of chloride, critical chloride content, carbonation coefficient, and sulfate resistance. Lastly, examples of comparative study results on some off-spec fly ashes (high free lime, dumped wet, and high LOI fly ashes) are demonstrated.