scholarly journals Comprehensive Investigation on the Potential of Fly Ash from New Source as Construction Material

2021 ◽  
Vol 23 (2) ◽  
pp. 78-90
Author(s):  
Antoni Antoni ◽  
Florentcia Hartono ◽  
Steven Tanuwijaya ◽  
Kevin Wijaya ◽  
Agie Vianthi ◽  
...  
Keyword(s):  
Fly Ash ◽  
Calcium Hydroxide ◽  
Alkaline Solution ◽  
Construction Material ◽  
High Volume ◽  
Comprehensive Investigation ◽  
Good Source ◽  
Cement Replacement ◽  
High Volume Fly Ash ◽  
Very High

Fly ash has been highly advocated to be re-utilized as a construction material. The most common utilization is to partially replace cement in a low-percentage scheme. However, there are several other schemes available to potentially use fly ash as binder in concrete that have not been widely exercised, especially those utilizing it in high to very high volume. In those schemes, high-volume fly ash (HVFA) concrete might use more than 50% fly ash to replace cement. To exploit its self-cementing properties, with or without the addition of other compounds, such as calcium hydroxide, fly ash might be used in very high percentage of cement replacement. In geopolymeric system, fly ash acts as the precursor of a stable binder, with the presence of highly alkaline solution. This paper demonstrates a model to investigate the potential of fly ash in several binder systems. The results show that fly ash from a good source can be utilized as an alternative binder in several different schemes.

scholarly journals Development of High Volume Fly Ash Concrete Incorporating Steel Fibre

2020 ◽  
Vol 9 (2) ◽  
pp. 426-433
Keyword(s):  
Fly Ash ◽  
Aspect Ratio ◽  
Thermal Power ◽  
High Volume ◽  
Fine Aggregate ◽  
Fly Ash Concrete ◽  
High Volume Fly Ash ◽  
Hardened Properties ◽  
Very High ◽  
Split Tensile Test

Concrete is most frequently used composite material. Concrete is homogeneous mix of fine aggregate, Coarse aggregate and binding medium of concrete paste .Due to `high demand of cement Co2 emission is very high, It leads to global warming. So in this project high volume fly ash concrete was incorporated. Fly ash is the waste material obtained from thermal power plant. In this paper we investigated about high volume fly ash in different percentage of replacement 55, 60, 75 percentage. Layered pavement is incorporated with Steel fiber in a different aspect ratio (15, 30, 40).layered pavement will give good thermal expansive properties. By varying fly ash content and Steel fibers Aspect ratio of different mixes were arrived hardened properties of these nine mixes were arrived such as Compression test, Split tensile test and Flexural test.

scholarly journals Mechanical Properties of High-Volume Fly Ash Strain Hardening Cementitious Composite (HVFA-SHCC) for Structural Application

Materials ◽  
2019 ◽  
Vol 12 (16) ◽  
pp. 2607 ◽  
Author(s):  
Chenhua Jin ◽  
Chang Wu ◽  
Chengcheng Feng ◽  
Qingfang Zhang ◽  
Ziheng Shangguan ◽  
...  
Keyword(s):  
Mechanical Properties ◽  
Fly Ash ◽  
Strain Hardening ◽  
Construction Material ◽  
High Volume ◽  
Partial Replacement ◽  
Cementitious Composite ◽  
Multiple Cracking ◽  
High Volume Fly Ash ◽  
Structural Applications

Strain-hardening cementitious composite (SHCC) is a kind of construction material that exhibits multiple cracking and strain-hardening behaviors. The partial replacement of cement with fly ash is beneficial to the formation of the tensile strain-hardening property of SHCC, the increase of environmental greenness, and the decrease of hydration heat, as well as the material cost. This study aimed to develop a sustainable construction material using a high dosage of fly ash (no less than 70% of the binder material by weight). Based on the micromechanics analysis and particle size distribution (PSD) optimization, six mixes with different fly ash to cement ratios (2.4–4.4) were designed. The mechanical properties of the developed high-volume fly ash SHCCs (HVFA-SHCCs) were investigated through tensile tests, compressive tests, and flexural tests. Test results showed that all specimens exhibited multiple cracking and strain-hardening behaviors under tension or bending, and the compressive strength of the designed mixes exceeded 30MPa at 28 days, which is suitable for structural applications. Fly ash proved to be beneficial in the improvement of tensile and flexural ductility, but an extremely high volume of fly ash can provide only limited improvement. The HVFA-SHCC mix FA3.2 (with fly ash to binder ratio of about 76% by weight) designed in this study is suggested for structural applications.

Evaluation of Compressive and Shear Strength Characteristics in High Volume Fly Ash Concrete

2014 ◽  
Vol 584-586 ◽  
pp. 1282-1288 ◽  
Author(s):  
Sung Won Yoo ◽  
Sang Hwa Jung ◽  
Seung Jun Kwon
Keyword(s):  
Shear Strength ◽  
Fly Ash ◽  
Construction Material ◽  
Cost Benefit ◽  
High Volume ◽  
Engineering Properties ◽  
Fly Ash Concrete ◽  
High Volume Fly Ash ◽  
Basic Parameters ◽  
Paper Engineering

HVFAC (High Volume Fly Ash Concrete) is an attractive construction material with cost benefit and reduced CO2emission. In this paper engineering properties such as compressive and shear strength are evaluated and their characteristics are investigated. For this work HVFAC with FA (Fly Ash) replacement ratio of 35% and 50% are prepared and strength (compressive, shear, and bond) are measured with basic parameters like elasticity and ultimate strain. Test results are compared with conventional predictions from Korea Structural Code and their applicabilities are evaluated. In bond strength and elasticity in HVFAC are evaluated to need reasonable coefficients for HVFAC design.

scholarly journals Optimization and Development of High-Strength High-Volume Fly Ash Concrete Mixes

2019 ◽  
Vol 8 (3) ◽  
pp. 5289-5293 ◽  
Keyword(s):  
Fly Ash ◽  
Activity Index ◽  
High Strength ◽  
High Volume ◽  
Past Research ◽  
Fly Ashes ◽  
Hydraulic Lime ◽  
Cement Replacement ◽  
Fly Ash Concrete ◽  
High Volume Fly Ash

Cement is the most abundantly used ingredient in the production of concrete due to which its production and use has increased manifold. To reduce the carbon footprint left by the cement production, fly ash is used as cement replacement in concrete. Past research studies suggest that the fly ash replacement can be upto 40% beyond which there will be drastic reduction of strength. In the present study, high strength concrete mix of 70 grade is developed with high volume fly ash of 70% as cement replacement. Silica fume of 10% and hydraulic lime of 30% are used as additives in the development of M70 grade high-strength high-volume fly ash concrete. In the present paper, three types of fly ashes are considered for the study of which one which is ultrafine is chosen based on the pozzolanic index and strength activity index. Excess lime needed for various percentage of fly ashes is evaluated based on the empirical equationsgiven by the Dunstan Jr andZayed

scholarly journals High Volume Fly Ash Self Compacting Concrete with Lime and Silica Fume as Additives

2020 ◽  
Vol 184 ◽  
pp. 01109
Author(s):  
C Chandana Priya ◽  
M V Seshagiri Rao ◽  
V Srinivasa Reddy ◽  
S Shrihari
Keyword(s):  
Fly Ash ◽  
Calcium Hydroxide ◽  
Silica Fume ◽  
High Volume ◽  
Hydrated Lime ◽  
Pozzolanic Reaction ◽  
Self Compacting Concrete ◽  
Conventional Concrete ◽  
High Volume Fly Ash ◽  
Reactive Silica

SCC is expensive when compared with normal conventional concrete. Hence, it is desired to produce low cost SCC by replacing cement with higher percentages of fly ash, which is a no cost material and available in abundance. At the same time to achieve higher grade HVFASCC, micro silica which is otherwise condensed silica fume can also be used along with fly ash to enhance the strength properties of HVFASCC. By replacing fly ash in high volumes in the mix, high amount of pozzolanic material becomes available, majorly reactive silica, for which more calcium hydroxide is necessary for further pozzolanic reaction. As we are reducing cement quantity, the amount of calcium hydroxide available is reduced thus demanding external addition of hydrated lime which can be supplied as additive to cater to the need of calcium hydroxide required for reactive silica in fly ash.The present investigation aims to achieve strength for high volume fly ash self-compacting concrete. The replacement of cement with fly ash is made in 45%, 50%, 55%, 60%, 65% and 70% with 20% hydrated lime and 10% silica fume in one trial. In another trial, 30% hydrated lime and 10% silica fume is added with replacement of fly ash to cement varying in same percentages. The design mix is tested for workability and flowability and cubes are casted for compression strength test and tested at 28 day,, 56 day, and 90 day,.

Very High Volume Fly Ash Cements. Early Age Hydration Study Using Na2 SO4 as an Activator

2013 ◽  
Vol 96 (3) ◽  
pp. 900-906 ◽  
Author(s):  
Shane Donatello ◽  
Ana Fernández-Jimenez ◽  
Angel Palomo
Keyword(s):  
Fly Ash ◽  
High Volume ◽  
Early Age ◽  
High Volume Fly Ash ◽  
Early Age Hydration ◽  
Very High

High temperature resistance of a very high volume fly ash cement paste

2014 ◽  
Vol 45 ◽  
pp. 234-242 ◽  
Author(s):  
Shane Donatello ◽  
Carsten Kuenzel ◽  
Angel Palomo ◽  
Ana Fernández-Jiménez
Keyword(s):  
High Temperature ◽  
Fly Ash ◽  
Cement Paste ◽  
High Volume ◽  
Temperature Resistance ◽  
High Volume Fly Ash ◽  
High Temperature Resistance ◽  
Very High

scholarly journals Compression Behavior of Confined Columns with High-Volume Fly Ash Concrete

2017 ◽  
Vol 2017 ◽  
pp. 1-11
Author(s):  
Sung-Won Yoo ◽  
Young Cheol Choi ◽  
Wonchang Choi
Keyword(s):  
Reinforced Concrete ◽  
Fly Ash ◽  
Construction Material ◽  
Concrete Columns ◽  
High Volume ◽  
Analysis Model ◽  
Replacement Rate ◽  
Reinforced Concrete Columns ◽  
High Volume Fly Ash ◽  
Structural Applications

The use of fly ash in ordinary concrete provides practical benefits to concrete structures, such as a gain in long-term strength, reduced hydration heat, improved resistance to chloride, and enhanced workability. However, few studies with high-volume fly ash (HVFA) concrete have been conducted that focus on the structural applications such as a column. Thus, there is a need to promote field applications of HVFA concrete as a sustainable construction material. To this end, this study investigated the compressive behavior of reinforced concrete columns that contain HVFA with a 50 percent replacement rate. Six columns were fabricated for this study. The study variables were the HVFA replacement rate, tied steel ratio, and tie steel spacing. The computed ultimate strength by the American Concrete Institute (ACI) code conservatively predicted the measured values, and, thus, the existing equation in the ACI code is feasible for confined RC columns that contain HVFA. In addition, an analysis model was calibrated based on the experimental results and is recommended for predicting the stress-strain relationship of confined reinforced concrete columns that contain HVFA.

Nanosilica Activated High Volume Fly Ash Concrete: Effects on Selected Properties

2016 ◽  
Vol 722 ◽  
pp. 157-162 ◽  
Author(s):  
Martin Labaj ◽  
Rudolf Hela ◽  
Iveta Hájková
Keyword(s):  
Fly Ash ◽  
Raw Materials ◽  
Water Pressure ◽  
Construction Material ◽  
High Volume ◽  
Strength Development ◽  
Early Age ◽  
Fly Ash Concrete ◽  
High Volume Fly Ash ◽  
Static And Dynamic Moduli

By volume, there is no other material used as much as concrete. Its mechanical properties, durability and favorable price makes concrete the perfect construction material. In last few decades, we are seeing a growing trend of partial Portland cement’s replacement with secondary raw materials, most commonly with fly ash. So-called high volume fly ash (HVFA) concretes usually contains over 50% of it. While HVFA concrete’s long-term properties and price are improved over the classical one, its early age properties are often affected negatively. Here, a highly reactive pozzolans enters the scene. Materials like microsilica and metakaolin are known to accelerate concrete’s strength development and improve early age characteristics. In this paper, nanosilica is used for this purpose. These SiO2 nanoparticles possesses a much higher surface area and thus reactivity. Three mixtures with 0, 40 a 60% portland cement’s replacement with fly ash were prepared and tested with and without addition of small amount of nanosilica. Effects on compressive strength, static and dynamic moduli of elasticity and resistivity against water pressure were observed. Results clearly demonstrates that even with dosage in the range of tenths of percent, nanosilica can significantly improve concrete’s properties.

Sign in / Sign up

Export Citation Format

Share Document