A study on carbonation depth prediction for fly ash ...

A study on carbonation depth prediction for fly ash concrete. ... Abstract. Carbonation of fly ash concrete is studied by using two types of fly ash with different CaO contents. It is observed that under natural exposure environments, the carbonation rate is the highest when specimens are exposed in the city. ... ScienceDirect ® is a ...

A study on carbonation depth prediction for fly ash concrete

In this study, for ordinary concrete and for fly ash concrete with 15%, 30% and 45% fly ash replacement ratios by mass, the depth of fully carbonated zone and …

Research the carbonation depth equation of high volume fly ...

Carbonation resistance is an important performance of concrete,it affects the application of concrete in engineering. According to the characteristics of high volume fly ash pumping concrete,the main factors affecting concrete's carbonation resistance are waterbinder ratio,fly ash dosage,pumping agent dosage,sand ratio and carbonization time and so on.

Experimental study on the carbonation of fly ash concrete

Based on fly ash concrete carbonation test, the impacts of water-binder ratio, fly ash proportion and pouring side to concrete carbonation depths was studied. With the help of the influence coefficient Ks of steel bar existence, the carbonation situations of concrete specimen with steel bar existence are analysed. The research results indicate that steel bar existence can inhibit ...

Carbonation Depth Research of Concrete with Low-Volume Fly Ash

The use of fly ash is in harmony with the concept of sustainable development. This paper discusses the effect of replacing ratio of fly ash (FA), ambient relative humidity, temperature, curing age and w/c on carbonation of concrete made with low-volume FA. The process was accelerated in artificial carbonation laboratory by controlling 20% concentration of CO2, temperatures from 20°C to 60 °C ...

A Review on Carbonation Study in Concrete - IJIRST

improved by adding fly ash because the fly ash addition enhanced the microstructure of RFAC. According to Cengiz Duran Atis (2003), fly ash concrete made with 70% replacement ratio showed higher carbonation than that of 50% fly ash replacement concrete and Normal Portland Cement concrete for both moist and dry curing conditions.

Prediction of Concrete Carbonation Depth using Decision …

Prediction of Concrete Carbonation Depth using Decision Trees Woubishet Zewdu Taffese, Esko Sistonen and Jari Puttonen Aalto University, Department of Civil and Structural Engineering . P. O. Box 12100, FI-00076 Aalto, Finland . Abstract. In this work, three carbonation depth predicting models using decision tree approach are developed.

Prediction of Carbonation Depth of Concrete With Fly Ash

Depth of carbonation can be evaluated by compressive strength of concrete cured in water for 28 days, irrespective of the fly ash content of concrete. Carbonation depth of concrete with and without fly ash naturally exposed indoors can be predicted by the equation obtained by the accelerated carbonation …

Effect of cement types, mineral admixtures, and bottom ash ...

The curing sensitivity of concrete with cement Types 1, 3, and 5 as well as multiple powders consisting of cement, fly ash, and limestone powder was studied. Bottom ash was also used in the study as an internal curing agent and a partial substitution of fine aggregate.

Carbonation-Porosity-Strength Model for Fly Ash Concrete ...

Mar 25, 2002· The study involves two replacement ratios of fly ash, various water-to-cement ratios, use of superplasticizer, two curing conditions, and four concrete ages. Statistical models that relate accelerated carbonation depth to strength and porosity are presented.

Study of Durability of Concrete with Fly Ash as Fine ...

To study the durability of concrete with fly ash as fine aggregate subjected to alternative attacks of freeze-thaw and carbonation, the appearance, mass loss, relative dynamic modulus of elasticity, relative compressive strength, and carbonation depth of the concrete are investigated using cyclic tests under single carbonation, single freeze-thaw, and alternation of freeze-thaw and carbonation.

Study on Carbonation Resistance of High-Performance ...

Based on the mechanism of concrete carbonation, the effects of content of fly ash in the binder, the water to binder ratios, compound activator, and long-term curing on the carbonation depth of fly ash high-performance concrete are investigated. Experiment results are analyzed and compared with compressive strength development characteristic of fly ash high-performance concrete, and some ...

JKhunthongkeaw S T 2006 A study on carbonation depth ...

JKhunthongkeaw S T 2006 A study on carbonation depth prediction for fly ash from CIVIL ENGI CE544 at Near East University - Cyprus. ... Jkhunthongkeaw s t 2006 a study on carbonation depth ... S. T. (2006). A study on carbonation depth prediction for fly ash concrete.

7 Study on the Carbonation - j-cst.org

STUDY ON THE CARBONATION PROPERTIES OF FLY ASH CONCRETE USING A VACUUM INSTRUMENT CORROSION SCIENCE AND TECHNOLOGY Vol.6, No.4, 2007 187 Table 1. Comparison of the experimental conditions of the previous and new accelerated carbonation tests

Carbonation - University of Wisconsin-Milwaukee - …

The depth of carbonation increases with an increase in ASTM Class C fly ash content in concrete. Rate of carbonation of concrete can be increased up to three times in comparison to the concrete without fly ash, by replacing 50% cement with ASTM Class C fly ash. Therefore, such concrete has immense potential to sequester CO2.

Carbonation depth prediction of fly ash concrete subjected ...

Carbonation depth prediction of fly ash concrete subjected to 2-and 3-dimensional CO 2 attack. Authors; ... fly ash concrete 2D carbonation ... et al. A study on the performance of high performance fly ash concrete in the bridge construction. Fly Ash Comprehensive Utilization, ...

Carbonation resistance of GGBS concrete | Magazine of ...

This study presents an analysis of a 30 000 strong data matrix derived from 227 studies originating from 35 countries since 1968. Similar to the fly ash effect, the carbonation of concrete increases with the incorporation of ground granulated blast-furnace slag (GGBS), but …

Carbonation of Fly Ash Concrete and Micro-Hardness Analysis

The effects of carbonation age, fly ash content in the binder and the water to binder ratios on the carbonation depth of fly ash concrete is investigated and the micromechanical properties of the hardened paste and the inter facial transition zone is analyzed with the micro-hardness method.

Carbonation of fly ash concrete | Magazine of Concrete ...

The carbonation of fly ash concrete is reported, with particular emphasis on the role of curing. Concretes with nominal strength grades C25, C35 and C45 and a range of fly ash levels (0–50%) were exposed to various treatments during the first 28 days; i.e. different moist curing periods anda range of ambient temperatures and relative humidities after curing.

Carbonation depth prediction of fly ash concrete subjected ...

Abstract Based on accelerated carbonation test, 1D, 2D and 3D carbonation of high performance concrete with different fly ash contents (0%, 15%, 20%, 40%, 60%) were studied. The interaction coefficients of 2D and 3D carbonation are defined. The time-dependent coefficient n of carbon dioxide diffusion and the interaction coefficients K of 2D and 3D carbonation are analyzed.

Carbonation Test Study on Low Calcium Fly Ash Concrete

The depth of carbonation could be observed by spraying phenolphthalein solution on the fresh broken concrete surface. The test results show that adding fly ash into concrete results in the decrease of cement consumption and calcium hydroxide, so carbonation rate increases.

Carbonation of Fly Ash Concrete

This paper reports data from a study on the effect of curing and strength grade on the carbonation of concrete with and without fly ash. Three series of concrete mixtures were cast with strength grades of 25, 35, and 45 Mpa, within each series the level of fly ash ranged from 0 to 50% by mass of total cementitious material.

Carbonation of Concrete Research Papers - Academia.edu

The results show that the introduction of calcium hydroxide in the curing solution, provides a slightly enhancement of carbonation resistance. Based on the obtained results, the incorporation of calcium hydroxide in the initial composition seems to be useful to develop extra strength to carbonation of high volume of fly ash concrete.

PREDICTING DEPTH OF CARBONATION OF CONCRETE - A ...

water:binder ratio (w/b), curing conditions, and by using fly ash. The specimens were exposed to four different sites for natural carbonation, with the depth of carbonation measured periodically. The carbonation model developed is validated based on the experimental results and the limitations are pointed out. 1. INTRODUCTION

Experimental Study on Durability Improvement of Fly Ash ...

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. In the field of application fly ash concrete, the use of nonair-entraining mode and durability improving admixture is a valuable option.

Carbonation of fly ash concrete: laboratory and field data ...

The present study consists of investigating the carbonation resistance of two series of concrete mixtures designed for three classes of concrete (25, 35, and 45 MPa compressive strength at 28 d) and using American Society for Testing and Materials (ASTM) type I Portland cement and two commercially used fly ashes meeting the ASTM standards at the level of 20%, 35%, and 50% of the total weight ...

Performance-based design and carbonation of concrete with ...

the binder composition on the durability of concrete exposed to carbonation. 2.1. Materials The purpose of the experimental study is to apply a perfor-mance-based approach of durability to the design of a concrete mixture with 50% substitution of cement by fly ash (FA50). The performances of FA50 concrete mixture are compared to three ref-

STRESS-CARBONATION OF FLY ASH CONCRETE

concrete structural durability, especially for fly ash concrete structures exposed to air. Many experimental results and conclusions on the carbonation of fly ash concrete have been obtained and successfully applied in the service life prediction of field fly ash concrete structures [1-6].

CARBONATION RESISTANCE OF CONCRETE WITH XYPEX …

the cases of cement-only concrete and fly ash concrete. This implies that CCM coating is more efficient if applied before the concrete is exposed to carbonation [4]. Figure 4: Carbonation depth of carbonated specimen before coating Figure 5: Carbonation depth of carbonated fly ash concrete before coating 0 4 8 12 16 20 24 0 2 4 6 8 10 12 14

A model for predicting the carbonation depth of concrete ...

Request PDF on ResearchGate | A model for predicting the carbonation depth of concrete containing low-calcium fly ash | Low-calcium fly ash (FL) is a general product from the combustion of ...

Model for Simulating Carbonation of Fly Ash Concrete ...

The aim of this paper is to develop a model for simulating carbonation of fly ash concrete. The model describes the diffusion of gases (C O 2 and water vapor) in concrete by the mass balance equations and the Fick’s law of diffusion.The time dependent hydration, and pozzolanic and carbonation reactions were considered for evaluating the amount of calcium hydroxide in concrete.

A Model for Predicting the Carbonation Depth of SCC with ...

Using accelerated carbonation test, the effects of fly ash additions, tensile stress rates, and compressive stress rates on carbonation rate of SCC are studied. Based on the test results, a model considered both effects of fly ash addition and stress rate for predicting the carbonation depth of SCC under real environment conditions is set up.

Carbonation A Durability Threat for Concrete - nbmcw.com

If we assume that carbonation depth are directly related to durability of concrete, i.e. higher the carbonation depth lower will be durability, following conclusion can be given. The effect of 15% replacement by Fly Ash is not clear. Carbonation depth has increased for M25, M30, and M40 but decreased for M20 and M35.

<<:prise of mineral grinding machine manufacturerrajasthan>>:cost of polymer grinding machine in india