Design Method of Fly Ash Concrete Mix Proportion Based on Stable Paste-Aggregate Ratio

2012 ◽  
Vol 490-495 ◽  
pp. 2110-2114
Author(s):  
Qing Wei Sun ◽  
Han Zhu
Keyword(s):  
Fly Ash ◽  
Design Method ◽  
Concrete Strength ◽  
Cementitious Materials ◽  
Fly Ash Concrete ◽  
Mix Proportion ◽  
Absolute Volume ◽  
Concrete Mix ◽  
Binder Ratio ◽  
Current Design

According to problems with the paste to aggregate ratio increases significantly and lack of recognition to cementitious materials effect of fly ash in current design method of fly ash concrete mix proportion, the paper introduces a new design method of fly ash concrete mix proportion that completely bases on the stable paste to aggregate ratio. The thoughts of parts of cement replaced by equal fly ash or by excessive fly ash in traditional method are not used in this method that starting from the stable paste to aggregate ratio directly, and using the connections of water-binder ratio and concrete strength to deduce the calculation formula of fly ash concrete mix proportion with method of absolute volume. The paper sums up the calculation steps of this new method, and combines with an example to verify the feasibility and effectiveness of this method.

Prediction Model for Cementing Efficiency of Fly Ash Concrete by Statistical Analyses

2011 ◽  
Vol 250-253 ◽  
pp. 1293-1296 ◽  
Author(s):  
Hong Bum Cho ◽  
Nam Yong Jee
Keyword(s):  
Fly Ash ◽  
Prediction Model ◽  
Statistical Analyses ◽  
Test Results ◽  
Construction Sites ◽  
K Value ◽  
Fly Ash Concrete ◽  
Mix Proportion ◽  
Wide Range ◽  
Binder Ratio

This paper offers the model that can estimate the cementing efficiency of fly ash (k value) based on a mix proportion of concrete containing fly ash (FA). The prediction model was derived using various statistical analyses, based on a wide range of mix proportions and a number of strength test results of ready mixed concretes used in eight construction sites. The k value increases with increasing water-binder ratio. As the FA replacement ratios increase, the k value increases at FA replacement ratios of less than 15%, but decreases at ratios of 15% or more. The k values obtained from the cementing efficiency estimate model range from 0.1 to 2.1.

scholarly journals Effect of Nano-CaCO3 on the Mechanical Properties and Durability of Concrete Incorporating Fly Ash

2020 ◽  
Vol 2020 ◽  
pp. 1-10
Author(s):  
Yanqun Sun ◽  
Peng Zhang ◽  
Weina Guo ◽  
Jiuwen Bao ◽  
Chengping Qu
Keyword(s):  
Mechanical Properties ◽  
Fly Ash ◽  
Second Phase ◽  
Fly Ash Concrete ◽  
Concrete Mixtures ◽  
Orthogonal Experiments ◽  
Mix Proportion ◽  
Electron Microscopy Analysis ◽  
Binder Ratio ◽  
Durability Of Concrete

Concrete mixtures consisting of nanomaterials and fly ash have been shown to be effective for improving the performance of concrete. This study investigates the combined effects of nano-CaCO3 and fly ash on the mechanical properties and durability of concrete; the mix proportion is optimized through orthogonal experiments. In the first phase, nine concrete mixtures were prepared with three water-to-binder ratios (0.4, 0.5, and 0.6), three fly ash contents (15%, 20%, and 25% replacement of the cement weight), and three nano-CaCO3 contents (1%, 2%, and 3% replacement of the cement weight). Based on the orthogonal analysis, the optimal concrete mix proportion was determined as a water-to-binder ratio of 0.4, 20% fly ash, and 1% nano-CaCO3. In the second phase, further investigations were carried out to examine the superiority of the optimal concrete and evaluate the synergistic effect of nano-CaCO3 and fly ash. The results showed that nano-CaCO3 contributed to increasing the compressive strength of fly ash concrete at the early ages, but its effect was quite limited at later ages. Furthermore, the scanning electron microscopy analysis revealed that the seeding effect, filling effect, and pozzolanic effect were the primary mechanisms for the improvement of concrete performance.

Research on Mix Proportion Design Method of Cement Concrete for Road Mixed with Antifreeze Admixtures Sealed in Capsules

2020 ◽  
Vol 861 ◽  
pp. 429-437
Author(s):  
Yang Zhao ◽  
Hong Fa Yu ◽  
Wei Dong Wang ◽  
Yue Li
Keyword(s):  
Fly Ash ◽  
Flexural Strength ◽  
Design Method ◽  
Orthogonal Design ◽  
Ash Content ◽  
Material Content ◽  
Mix Proportion ◽  
Binder Ratio ◽  
Feeding Process ◽  
Water Binder Ratio

In order to explore the influence of a new mixed type antifreeze material on the flexural strength of concrete for road, the orthogonal design method was used to conduct experimental research on six factors including the water-binder ratio, the antifreeze material content, the fly ash content, the feeding process, the shape of the antifreeze material and the pre-absorption of antifreeze material. The influence degree of various factors on the flexural strength of concrete was studied, and the mixing ratio design method of concrete for road mixed with the antifreeze material was given. It was found that the water-binder ratio is the main factor affecting the strength of the concrete and that when the amount of antifreeze material is less than 15%, the effect on the strength is small. The influence of other factors on the strength is greatly influenced by the interaction of water-binder ratio. When it comes to the mix design, the content of gelling material is 500 kg/m3, and the water-binder ratio changes from 0.35 to 0.43 under different traffic levels. The recommended antifreeze material content and fly ash content is 10% and 15% respectively. It’s also suggested that the antifreeze material should be pre-absorbed, and the cement sand and stone be mixed before the antifreeze material is put into the mixing.

scholarly journals LONG-TERM CHARACTERISTICS OF HIGH VOLUME FLY ASH CONCRETE STRENGTH AND DESIGN METHOD FOR THICKNESS OF THE PAVEMENT

2007 ◽  
Vol 63 (1) ◽  
pp. 66-71 ◽  
Author(s):  
Yasuhiro KATO ◽  
Sumio HAMADA ◽  
Takao ICHIOKA ◽  
Ryota KOBAYASHI
Keyword(s):  
Fly Ash ◽  
Design Method ◽  
Concrete Strength ◽  
High Volume ◽  
Fly Ash Concrete ◽  
High Volume Fly Ash

Effects of Concrete Mix Proportion on Electrical Resistivity of Concrete

2016 ◽  
Vol 866 ◽  
pp. 68-72 ◽  
Author(s):  
Su Wai Hnin ◽  
Pakawat Sancharoen ◽  
Somnuk Tangtermsirikul
Keyword(s):  
Compressive Strength ◽  
Electrical Resistivity ◽  
Fly Ash ◽  
Ionic Species ◽  
Ash Content ◽  
Curing Conditions ◽  
Mix Proportion ◽  
Concrete Mix ◽  
Binder Ratio ◽  
Paste Content

Electrical resistivity is one of the important parameters for modeling corrosion behavior of concrete. Few researchers have been carried out to investigate this problem. This paper presents an experimental study on effects of concrete mix proportion on electrical resistivity of concrete. The electrical resistivity of concrete is measured using the four Wenner probe, which is a fast and simple test that evaluates the resistance of concrete against the entrance of ionic species. The varied parameters in this study were water/binder ratio, fly ash content, cement paste content (Υ) and curing conditions. Based on experimental results, a good correlation is obtained between electrical resistivity and compressive strength of concrete.The results showed that the electrical resistivity of concrete mainly depend on compressive strength and fly ash content. The results of this study can be used further to model the behavior of electrical resistivity of concrete when the mix proportions are provided and that can be supported information to design sacrificial anode protection system.

The Research on Dense Packing Concrete Mix Proportion

2011 ◽  
Vol 287-290 ◽  
pp. 1043-1047
Author(s):  
Shao Wei Yao ◽  
Chang Rui Wang ◽  
Zhen Guo Gao
Keyword(s):  
Fly Ash ◽  
Design Method ◽  
Dense Packing ◽  
Research Results ◽  
Mix Proportion ◽  
Concrete Mix ◽  
Aggregate Effect ◽  
Packing Method

According to the postulation on dense packing of aggregates, the paper discusses the dense packing method of various aggregates and its coefficients, and offers the mix proportion design method of concrete. The research results indicate that using method of the mix proportion design based on the theory on dense packing of aggregates, aggregates can play a maximum role, especially the micro-aggregate effect of the fly ash, then the compactness of concrete is raised effectively, the quantity of cement is reduced and the endurance of concrete is improved.

Effect of ground granulated blast funrnace slag and fly ash on strength, permeability, and under-water abrasion of fine-grained concrete

2020 ◽  
Vol 71 (7) ◽  
pp. 775-788
Author(s):  
Quyet Truong Van ◽  
Sang Nguyen Thanh
Keyword(s):  
Fly Ash ◽  
Concrete Strength ◽  
Cementitious Materials ◽  
Supplementary Cementitious Materials ◽  
Chloride Permeability ◽  
Cement Replacement ◽  
Fine Grained ◽  
Granulated Blast Furnace Slag ◽  
Compressive Strength Test ◽  
Economic Ground

The utilisation of supplementary cementitious materials (SCMs) is widespread in the concrete industry because of the performance benefits and economic. Ground granulated blast furnace slag (GGBFS) and fly ash (FA) have been used as the SCMs in concrete for reducing the weight of cement and improving durability properties. In this study, GGBFS at different cement replacement ratios of 0%, 20%, 40% and 60% by weight were used in fine-grained concrete. The ternary binders containing GGBFS and FA at cement replacement ratio of 60% by weight have also evaluated. Flexural and compressive strength test, rapid chloride permeability test and under-water abrasion test were performed. Experimental results show that the increase in concrete strength with GGBFS contents from 20% to 40% but at a higher period of maturity (56 days and more). The chloride permeability the under-water abrasion reduced with the increasing cement replacement by GGBFS or a combination of GGBFS and FA

scholarly journals Experimental Study on Durability Improvement of Fly Ash Concrete with Durability Improving Admixture

2014 ◽  
Vol 2014 ◽  
pp. 1-11 ◽  
Author(s):  
Hong-zhu Quan ◽  
Hideo Kasami
Keyword(s):  
Fly Ash ◽  
Experimental Studies ◽  
Drying Shrinkage ◽  
Replacement Ratio ◽  
Fly Ash Concrete ◽  
Air Content ◽  
Carbonation Resistance ◽  
Binder Ratio ◽  
Water Binder Ratio

In order to improve the durability of fly ash concrete, a series of experimental studies are carried out, where durability improving admixture is used to reduce drying shrinkage and improve freezing-thawing resistance. The effects of durability improving admixture, air content, water-binder ratio, and fly ash replacement ratio on the performance of fly ash concrete are discussed in this paper. The results show that by using durability improving admixture in nonair-entraining fly ash concrete, the compressive strength of fly ash concrete can be improved by 10%–20%, and the drying shrinkage is reduced by 60%. Carbonation resistance of concrete is roughly proportional to water-cement ratio regardless of water-binder ratio and fly ash replacement ratio. For the specimens cured in air for 2 weeks, the freezing-thawing resistance is improved. In addition, by making use of durability improving admixture, it is easier to control the air content and make fly ash concrete into nonair-entraining one. The quality of fly ash concrete is thereby optimized.

On Effects of Fly Ash as a Partial Replacement of Cement on Concrete Strength

2012 ◽  
Vol 204-208 ◽  
pp. 3970-3973
Author(s):  
Reagan J. Case ◽  
Kai Duan ◽  
Thuraichamy G. Suntharavadivel
Keyword(s):  
Compressive Strength ◽  
Fly Ash ◽  
Concrete Strength ◽  
Cementitious Materials ◽  
Partial Replacement ◽  
Replacement Ratio ◽  
Interface Reactions ◽  
Compressive Strength Of Concrete ◽  
Interface Bonding Strength ◽  
Large Research

As a part of a large research program aiming at the cementitious materials containing recycled materials at Central Queensland University – Australia, the current paper presents the preliminary results of a study on the effects of fly ash, which is used to replace cement in concrete, on the concrete compressive strength. For this purpose, systematic experiments have been carried out to investigate the influences of fly ash ratio and age. The compressive strength of concrete specimens with replacement ratios of 15%, 30% and 45%, and aged 7 and 28 days are measured and are compared with those of the concrete specimens without fly ash at the same ages. The results demonstrate that the strength of fly ash containing concrete improves more slowly but more strongly with aging, than their fly ash free counterparts, and an optimum fly ash replacement ratio exists where the maximum compressive strength of fly ash containing concrete can be achieved, and the maximum strength for the specimens aged 28 days and above is higher that of fly ash free concrete. Furthermore, the observation strength behaviours are analysed and discussed in terms of the influences of fly ash on interface reactions and interface bonding strength.

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