Carbonation mechanism of alkali-activated fly ash and slag ...

The relationship between carbonation rate, pore solution chemistry and microstructure was investigated. An advanced microstructure characterization of fly ash (FA) and ground granulated blast furnace slag (GGBFS) was performed using PARC software.

Accelerated and natural carbonation of concrete with high ...

Fly ash (FA) already has a long history of being used as partial replacement of ordinary Portland cement (OPC) in concrete. When focusing on high-volume fly ash (HVFA) concrete, special attention should go to environments subject to atmospheric CO 2 ingress and carbonation-induced steel corrosion.

Durability of Self-Compacting Concrete with Fly Ash …

The present paper presents the influence of fly ash on the properties of fresh concrete and the durability of self-compacting concrete (SCC). Using fly ash as a partial cement replacement reduces both production costs and pollution due to the impressive amount of CO 2 from cement production.

Carbonation of Fly Ash Concrete

The results show that the carbonation of concrete with 15% to 30% fly ash is similar to or slightly higher than equivalent strength concrete without fly ash. Concrete containing 50% fly ash carbonated at a significantly faster rate than control specimens of the same grade and the differences were particularly marked for poorly cured concretes ...

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

Nagataki, S., Ohga, H., and Kim, E.K. 1986. Effect of curing conditions on the carbonation of concrete with fly ash and the corrosion of reinforcement in long term tests. In Proceedings of the 2nd International Conference on the Use of Fly Ash, Silica Fume, Slag, and Natural Pozzolans in Concrete, Madrid, 1986.

Carbonation of Concrete Incorporating High Volumes of Fly Ash

This investigation deals with determining the carbonation resistance of high-volume fly ash concrete. Five air-entrained concrete mixtures were studied consisting of three high-volume fly ash concrete mixtures (HVFA) incorporating 58% of fly ash by mass of the total cementitious materials made with a water-cementitious materials ratio (w/cm) of ...

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 a blended slag-fly ash geopolymer concrete ...

Request PDF on ResearchGate | On Oct 1, 2016, Kirubajiny Pasupathy and others published Carbonation of a blended slag-fly ash geopolymer concrete in field conditions after 8years

Influence of Fineness of Fly Ash on the Carbonation and ...

Sep 09, 2011· The paper presents an investigation on the influence of the fineness of fly ash on the carbonation and electrical conductivity of concrete. Fly ash collected from three thermal power stations in India (with a Blaine's fineness of 200, 255, and 305 m 2 / kg, respectively) were used for this study.The study also involved three replacement levels (15, 25, and 35% of cementitious materials) for ...

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 ...

Carbonation resistance of fly ash concrete | Request PDF

Request PDF on ResearchGate | Carbonation resistance of fly ash concrete | Based on systematic analysis, evaluation and synthesis of a 30 000 strong data matrix generated from 213 studies from 33 ...

Influence of Carbonation on the Chloride Diffusion in Concrete

Especially, investigation of the diffusion . ... characteristics according to the structure and carbonation of concrete in the specimens mixed with fly ash . 1194 (a) Type I, w/c 38%, fly ash 0% (c) Type V, w/c 38%, fly ash 20% ... when carbonation of concrete is processing, the concentration of chloride ion increases due to the crystallization ...

JOINT EFFECTS OF EXPANSIVE ADMIXTURE AND FLY ASH …

JOINT EFFECTS OF EXPANSIVE ADMIXTURE AND FLY ASH ON THE CARBONATION RATE OF CONCRETE Zhonghe Shui (1), Liuqing Tu (1, 2), Wei Chen (1), Juntao Ma (1) and Wenbing Xu (1) (1) School of Materials Science and Engineering, Wuhan University of Technology, China (2) CCCC Wuhan Harbour Engineering Design and Research Co.,Ltd, China Abstract

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.

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 and microstructural analysis of Low ...

Nov 30, 2016· The carbonation resistance of LVFA and HVFA based SCC made with coarse RCA have been investigated. ... The present study investigates the carbonation resistance of Low Volume Fly Ash (LVFA) and High Volume Fly Ash (HVFA) based Self Compacting Concrete (SCC) made with Coarse Recycled Concrete Aggregates (RCA). ...

Effect of mineral additive use on permeation properties of ...

In this study, effect of fly ash, silica fume and blast furnace slag to the permeation of concrete was investigated. The differences in the absorption, capillary sorption, and ultrasound transmission speed of concrete with and without mineral additives have been studied.

Carbonation resistance of fly ash and blast furnace slag ...

The carbonation resistance of fly ash (FA) & blast furnace slag (BFS)-based geopolymer (GP) concrete were investigated in detail by theoretical analysis and the accelerated carbonation test. • Carbonation rates of the ambient cured GP concrete and GP mortar were modeled by power functions. •

CARBONATION IN CONCRETE AND EFFECT ON STEEL …

initiation of carbonation-induced corrosion may be shortened by -360% when the fly ash cement replacement is increased from 20% to 50%. The initiation time may be shortened by ;:35 when cement replacement is increased from 20% fly ash to 20% fly ash plus 8% silica fume. 17 KeyWardr Reinforcing Steel, Corrosion. Carbonation, Concrete,

Storing CO2 in Built Infrastructure: CO Carbonation of ...

Carbonation of Precast Concrete Products . 4. Raw materials carbonation. Material source: Carbonation reactivity of waste-derived materials largely varies on the source of materials • Steel slag • Coal power plant: fly ash (low CaO) • Coal power plant: fly ash (high CaO ) Progress - Task 2. Development of carbonation process

Sess ion A 4: DURABILITY OF CONCRETE WITH 83 …

The investigation is part of a PhD study on carbonation- induced corrosion in fly ash concrete. In the project two different accelerated conditions were used in addition to natural conditions: one to accelerate carbonation (60% RH and 1% CO2) and one where also corrosion in carbonated concrete is facilitated (90% RH and 5% CO 2). The aim of the ...

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 …

Experimental Study on Durability Improvement of Fly Ash ...

The effects of durability improving admixture, air content, water-binder ratio, and fly ash replacement ratio on strength development, drying shrinkage, carbonation, and freezing-thawing resistance of fly ash concrete are to be investigated.

Influence of Blended Cements with Calcareous Fly Ash on ...

The investigation included five new cements made with different contents of non-clinker constituents: calcareous fly ash, siliceous fly ash, ground granulated blastfurnace slag, and a reference cement—ordinary Portland cement. The influence of innovative cements on the resistance of concrete to chloride and carbonation exposure was studied.

Carbonation of concrete - Chalmers Publication Library (CPL)

2.5.1 Carbonation of fly ash concretes 13 2.5.2 Carbonation of GGBS concretes 13 2.6 Chloride ingress and chloride induced corrosion 14 2.7 Relation between chloride ingress and carbonation 15 2.8 Accelerated carbonation 15 2.9 Concrete standards in Sweden and Europe 16 2.9.1 The k-value concept for fly ash and GGBS 17

Design of Fly-Ash Concrete Masonry for Optimal Carbon ...

Design of Fly -Ash Concrete Masonry for Optimal Carbon Sequestration Andrew J. Salber, Christopher W. Swan 1 1 Tufts University, Department of Civil and Environmental Engineering, 200 College Avenue, Medford, MA 02155 KEYWORDS: concrete, masonry, fly ash, carbonation…

Papers by Keyword: Carbonation - scientific.net

Abstract: 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 AND GGBS CONCRETE

carbonation depth of concrete made with FA and GGBS is likely to exceed the specified cover in the Eurocode 2 specification. Measures to minimise the carbonation effect of these materials are also discussed. Keywords: Fly ash, Ground granulated blast furnace slag, Carbonation, Structural concrete