Using in-situ observation to understand the leaching behavior of Portland cement and alkali-activated slag pastes

Alkali activated slag (AAS) offers opportunities to the construction industry as an alternative to ordinary Portland cement (OPC). The production of OPC and its use contributes significantly to release of CO2 into the atmosphere while AAS is an industrial by-product that contributes much less to the environmental footprint that needs to be recycled if not landfilled. This paper outlines some of the key properties, merits and demerits of AAS when used as alternative to OPC. Competitive compressive strength of AAS concrete is amongst of the advantages of replacing cement with AAS while high shrinkage and carbonation levels are potential disadvantages.

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(Micro)-structural comparison between geopolymers, alkali-activated slag cement and Portland cement

Journal of the European Ceramic Society ◽

10.1016/j.jeurceramsoc.2005.12.021 ◽

2006 ◽

Vol 26 (16) ◽

pp. 3789-3797 ◽

Cited By ~ 249

Author(s):

I. Lecomte ◽

C. Henrist ◽

M. Liégeois ◽

F. Maseri ◽

A. Rulmont ◽

...

Keyword(s):

Portland Cement ◽

Structural Comparison ◽

Slag Cement ◽

Alkali Activated Slag ◽

Activated Slag ◽

Alkali Activated

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A Low-Autogenous-Shrinkage Alkali-Activated Slag and Fly Ash Concrete

Applied Sciences ◽

10.3390/app10176092 ◽

2020 ◽

Vol 10 (17) ◽

pp. 6092

Author(s):

Zhenming Li ◽

Xingliang Yao ◽

Yun Chen ◽

Tianshi Lu ◽

Guang Ye

Keyword(s):

Fly Ash ◽

Portland Cement ◽

High Performance ◽

Structural Engineering ◽

Autogenous Shrinkage ◽

Portland Cement Concrete ◽

Alkali Activated Slag ◽

Cracking Potential ◽

Activated Slag ◽

Alkali Activated

Alkali-activated slag and fly ash (AASF) materials are emerging as promising alternatives to conventional Portland cement. Despite the superior mechanical properties of AASF materials, they are known to show large autogenous shrinkage, which hinders the wide application of these eco-friendly materials in infrastructure. To mitigate the autogenous shrinkage of AASF, two innovative autogenous-shrinkage-mitigating admixtures, superabsorbent polymers (SAPs) and metakaolin (MK), are applied in this study. The results show that the incorporation of SAPs and MK significantly mitigates autogenous shrinkage and cracking potential of AASF paste and concrete. Moreover, the AASF concrete with SAPs and MK shows enhanced workability and tensile strength-to-compressive strength ratios. These results indicate that SAPs and MK are promising admixtures to make AASF concrete a high-performance alternative to Portland cement concrete in structural engineering.

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THERMAL RESISTANCE OF ALKALI ACTIVATED SLAG CONCRETE

Proceedings of International Structural Engineering and Construction ◽

10.14455/isec.res.2017.96 ◽

2017 ◽

Vol 4 (1) ◽

Author(s):

Kiacher Behfarnia ◽

Mohammad Shahbaz

Keyword(s):

Portland Cement ◽

Thermal Resistance ◽

Physical And Mechanical Properties ◽

Decisive Role ◽

Portland Cement Concrete ◽

Alkali Activated Slag ◽

Binding Effect ◽

And Performance ◽

Activated Slag ◽

Alkali Activated

This study investigated the thermal resistance of Alkali Activated Slag (AAS) concrete. Alkali Activated Slag cement is an environmentally friendly alternative to Portland cement, which can be produced by using an alkaline solution to activate the binding effect of the blast furnace slag. Heat from fire changes the physical and mechanical properties of concrete. Given the decisive role of thermal resistance in the operation and performance of structures, it is necessary to evaluate the effect of heat on the performance of AAS concrete. In this study, a series of tests were arranged to examine the effect of slag percentage on thermal resistance of AAS concrete. AAS concrete samples from mixes, with different slag percentage, were subjected to 20, 200, 400, 600, and 800˚C temperature and change in their compressive strength were measured and compared with that of samples made by ordinary Portland cement concrete. The results show that the thermal resistance of AAS concrete is higher than ordinary concrete.

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Differences in Electrical Properties of Portland Cement and Alkali-Activated Slag Mortars

Solid State Phenomena ◽

10.4028/www.scientific.net/ssp.276.15 ◽

2018 ◽

Vol 276 ◽

pp. 15-20 ◽

Cited By ~ 1

Author(s):

Pavel Rovnaník ◽

Maria Míková ◽

Ivo Kusák ◽

Patrik Bayer

Keyword(s):

Electrical Properties ◽

Portland Cement ◽

Building Materials ◽

Elevated Temperatures ◽

Sodium Ions ◽

Alkali Activated Slag ◽

Self Heating ◽

Chemical Attack ◽

Activated Slag ◽

Alkali Activated

Alkali-activated slag is known as a building material for more than sixty years and is considered an alternative to Portland cement based binders. Compared to Portland cement it exhibits some superior properties such as higher resistance against chemical attack and exposure to elevated temperatures. Aluminosilicate binders are generally electrical insulators; however, electrical properties of building materials gain the importance in the new field of applications such as self-sensing or self-heating materials. This paper brings a comparison of the electrical properties, especially resistance and capacitance, between Portland cement and alkali-activated slag mortars. The measurements revealed that alkali-activated slag shows enhanced conducting properties due to the presence of mobile hydrated sodium ions and metallic iron microparticles.

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