scholarly journals Effects of the Loss on Ignition of Fly Ash on the Properties of High-Volume Fly Ash Concrete

2019 ◽  
Vol 11 (9) ◽  
pp. 2704 ◽  
Author(s):  
How-Ji Chen ◽  
Neng-Hao Shih ◽  
Chung-Hao Wu ◽  
Shu-Ken Lin
Keyword(s):  
Compressive Strength ◽  
Fly Ash ◽  
Modulus Of Elasticity ◽  
High Volume ◽  
Cementitious Materials ◽  
Hardened Concrete ◽  
Fine Aggregate ◽  
Loss On Ignition ◽  
High Volume Fly Ash ◽  
Hardened Properties

This study presents the experimental results of fresh and hardened properties of concrete incorporating high-volume fly ash (HVFA). Two kinds of low-calcium fly ash with loss on ignition (LOI) of 5% and 8% were used as replacement for cement and/or fine aggregate of 0% (control), 20%, 40%, 50%, 60% and 80% by weight of the total cementitious materials. The properties of fresh concrete tested included the slump, air content, unit weight and setting time; those of hardened concrete determined included compressive strength, modulus of elasticity, flexural strength and drying shrinkage. Test results indicate that the concretes made with high-LOI (8%) fly ash can be successfully produced for structural concrete, which contains fly ash of up to 60% of the total cementitious materials. The high-LOI fly ash-concretes with higher replacement levels presented longer setting times. However, although both the fresh and hardened properties of high LOI fly ash concretes were inferior to those of the low-LOI (5%) fly ash concretes, the high modulus of elasticity, the adequate strength development characteristics both at early and later ages (up to 365 days) and the low dry shrinkage were observed when compared to those of the control concrete with a comparable 28-day compressive strength of 30 MPa.

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 Utilization of Crumb Rubber and High-Volume Fly Ash in Concrete for Environmental Sustainability: RSM-Based Modeling and Optimization

Materials ◽  
2021 ◽  
Vol 14 (12) ◽  
pp. 3322
Author(s):  
Mugineysh Murali ◽  
Bashar S. Mohammed ◽  
Isyaka Abdulkadir ◽  
M. S. Liew ◽  
Wesam Salah Alaloul
Keyword(s):  
Fly Ash ◽  
Environmental Sustainability ◽  
High Volume ◽  
Crumb Rubber ◽  
Cementitious Materials ◽  
Partial Replacement ◽  
Fine Aggregate ◽  
High Volume Fly Ash ◽  
Concrete Production ◽  
Rubber Concrete

Waste tire and fly ash (FA) are two waste materials whose disposal and rapid rate of accumulation are among the pressing sources of concern and threat to the environment. Although much research exists on the use of these materials in cementitious composites, very little literature is available on the effectiveness of combining them in high volumes for concrete production. This work aimed to utilize crumb rubber (CR) from waste tires as a partial replacement of fine aggregate at 15%, 22.25%, and 30% by volume, and high-volume fly ash (HVFA) replacement of cement at 50%, 60%, and 70% (by weight of cementitious materials) to produce high-volume fly ash–crumb rubber concrete (HVFA–CRC). Using the central composite design (CCD) option of the response surface methodology (RSM), 13 mixes were produced with different combinations and levels of the CR and FA (the input factors) on which the responses of interest (compressive, flexural, and tensile strengths) were experimentally investigated. Furthermore, the composite influence of CR and HVFA on the workability of the concrete was assessed using the slump test. The results showed a decline in the mechanical properties with increasing replacement levels of the CR and HVFA. However, up to 22.25% and 60% of CR and HVFA replacements, respectively, produced a structural HVFA–CRC with a compressive strength of more than 20 MPa at 28 days. Response predictive models were developed and validated using ANOVA at a 95% confidence level. The models had high R2 values ranging from 95.26 to 97.74%. Multi-objective optimization was performed and validated with less than 5% error between the predicted and experimental responses.

scholarly journals Study on using maximum amount of fly ash in producing ultra-high performance concrete

2018 ◽  
Vol 12 (3) ◽  
pp. 51-61
Author(s):  
Van Viet Thien An
Keyword(s):  
Compressive Strength ◽  
Fly Ash ◽  
High Performance ◽  
High Performance Concrete ◽  
High Volume ◽  
Cementitious Materials ◽  
Maximum Amount ◽  
Ultra High Performance Concrete ◽  
Design Expert ◽  
High Volume Fly Ash

In the present study, the synergic effects of cementitious materials in the ternary binder containing cement, silica fume, fly ash on the workability and compressive strength were evaluated by using the D-optimal design of Design-Expert 7. The ternary binder composed of 65 vol.-% cement, 15 vol.-% SF and 20 vol.-% FA at the W/Fv ratio of 0.50 is the optimum mixture proportions for the highest compressive strength of the UHPC. To produce the sustainable UHPC, high-volume fly ash ultra high performance concrete with a good flowability and 28-d compressive strength over 130 MPa can be produced with fly ash content up to 30 vol.-% in the binder. Article history: Received 21 March 2018, Revised 06 April 2018, Accepted 27 April 2018

scholarly journals Influence of Particle Size Distribution of High Calcium Fly Ash on HVFA Mortar Properties

2018 ◽  
Vol 20 (2) ◽  
pp. 51
Author(s):  
Antoni . ◽  
Hendra Surya Wibawa ◽  
Djwantoro Hardjito
Keyword(s):  
Particle Size ◽  
Compressive Strength ◽  
Fly Ash ◽  
Particle Size Distribution ◽  
Size Distribution ◽  
Setting Time ◽  
High Volume ◽  
High Volume Fly Ash ◽  
High Calcium ◽  
High Calcium Fly Ash

This study evaluates the effect of particle size distribution (PSD) of high calcium fly ash on high volume fly ash (HVFA) mortar characteristics. Four PSD variations of high calcium fly ash used were: unclassified fly ash and fly ash passing sieve No. 200, No. 325 and No. 400, respectively. The fly ash replacement ratio of the cementitious material ranged between 50-70%. The results show that with smaller fly ash particles size and higher levels of fly ash replacement, the workability of the mixture was increased with longer setting time. There was an increase in mortar compressive strength with finer fly ash particle size, compared to those with unclassified ones, with the highest strength was found at those with fly ash passing mesh No. 325. The increase was found due to better compactability of the mixture. Higher fly ash replacement reduced the mortar’s compressive strength, however, the rate was reduced when finer fly ash particles was used.

Effect of Curing Temperature on Hardened Concrete Properties

2005 ◽  
Vol 1914 (1) ◽  
pp. 97-104 ◽  
Author(s):  
W. Micah Hale ◽  
Thomas D. Bush ◽  
Bruce W. Russell ◽  
Seamus F. Freyne
Keyword(s):  
Fly Ash ◽  
Cementitious Materials ◽  
Curing Temperature ◽  
Supplementary Cementitious Materials ◽  
Cold Weather ◽  
Strength Development ◽  
Hardened Concrete ◽  
Hardened Properties ◽  
Hot Weather ◽  
Materials Used

Often, concrete is not mixed or placed under ideal conditions. Particularly in the winter or the summer months, the temperature of fresh concrete is quite different from that of concrete mixed under laboratory conditions. This paper examines the influence of supplementary cementitious materials on the strength development (and other hardened properties) of concrete subjected to different curing regimens. The supplementary cementitious materials used in the research program were ground granulated blast furnace slag (GGBFS), fly ash, and a combination of both materials. The three curing regimens used were hot weather curing, standard curing, and cold weather curing. Under the conditions tested, the results show that the addition of GGBFS at a relatively low replacement rate can improve the hardened properties for each curing regimen. This improvement was noticeable not only at later ages but also at early ages. Mixtures that contained both materials (GGBFS and fly ash) performed as well as and, in most cases, better than mixtures that contained only portland cement in all curing regimens.

scholarly journals Strength Development and Thermogravimetric Investigation of High-Volume Fly Ash Binders

Materials ◽  
2019 ◽  
Vol 12 (20) ◽  
pp. 3344 ◽  
Author(s):  
Zhiyuan Zhou ◽  
Massoud Sofi ◽  
Elisa Lumantarna ◽  
Rackel San Nicolas ◽  
Gideon Hadi Kusuma ◽  
...  
Keyword(s):  
Compressive Strength ◽  
Fly Ash ◽  
Temperature Rise ◽  
Bound Water ◽  
High Volume ◽  
Heat Of Hydration ◽  
New Method ◽  
Hydration Properties ◽  
Adiabatic Temperature Rise ◽  
High Volume Fly Ash

To address sustainability issues by facilitating the use of high-volume fly ash (HVFA) concrete in industry, this paper investigates the early age hydration properties of HVFA binders in concrete and the correlation between hydration properties and compressive strengths of the cement pastes. A new method of calculating the chemically bound water of HVFA binders was used and validated. Fly ash (FA) types used in this study were sourced from Indonesia and Australia for comparison. The water to binder (w/b) ratio was 0.4 and FA replacement levels were 40%, 50% and 60% by weight. Isothermal calorimetry tests were conducted to study the heat of hydration which was further converted to the adiabatic temperature rise. Thermo-gravimetric analysis (TGA) was employed to explore the chemically bound water (WB) of the binders. The results showed that Australian FA pastes had higher heat of hydration, adiabatic temperature rise, WB and compressive strength compared to Indonesian FA pastes. The new method of calculating chemically bound water can be successfully applied to HVFA binders. Linear correlation could be found between the WB and compressive strength.

Compressive strength and hydration of high-volume wet-grinded coal fly ash cementitious materials

2019 ◽  
Vol 206 ◽  
pp. 248-260 ◽  
Author(s):  
Hongbo Tan ◽  
Kangjun Nie ◽  
Xingyang He ◽  
Xiufeng Deng ◽  
Xun Zhang ◽  
...  
Keyword(s):  
Compressive Strength ◽  
Fly Ash ◽  
Coal Fly Ash ◽  
High Volume ◽  
Cementitious Materials
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