Characterization of Conventional and Modern Curing Techniques in Concrete

2016 ◽  
Vol 711 ◽  
pp. 1118-1125
Author(s):  
Wasim Khaliq ◽  
Waqas Javaid
Keyword(s):  
Compressive Strength ◽  
Material Properties ◽  
Experimental Program ◽  
Strength Development ◽  
Vital Importance ◽  
Uniform Microstructure ◽  
Curing Methods ◽  
Compressive Strength Development ◽  
Strength And Durability

Appropriate curing of concrete is of vital importance in development of desired material properties in concrete namely compressive strength, durability, and dense uniform microstructure. Improper and intermittent curing is considered as one of the major reasons for concrete failures as evident in the form of cracks that consequently lead to durability issues of structures. An experimental program was designed to study the behavior of concrete under various conventional and modern curing techniques. Numerous cylindrical specimens were tested with different conventional and modern curing techniques to quantify their effects on curing of concrete. Microstructural and compressive strength development analyses at different ages were conducted to monitor the effect of curing methods. This work is helpful in establishing the best curing techniques for attainment of compressive strength and durability in concrete.

Early Age Properties of Alkali Activated Brown Coal Fly Ash Binders

2014 ◽  
Vol 931-932 ◽  
pp. 457-462 ◽  
Author(s):  
Chandani Tennakoon ◽  
Kwesi Sagoe-Crentsil ◽  
Jay G. Sanjayan ◽  
Ahmad Shayan
Keyword(s):  
Compressive Strength ◽  
Fly Ash ◽  
Brown Coal ◽  
Coal Fly Ash ◽  
Coal Ash ◽  
Strength Development ◽  
Early Age ◽  
Compressive Strength Development ◽  
Strength And Durability ◽  
Reaction Processes

The present study evaluates potential re-use options for two different types of brown coal fly ash (class C) sourced from Australia as feedstock for geopolymer binder systems. The study covers analysis of fundamental material and mix-design requirements for geopolymer binders as a basis to achieve durable brown coal ash geopolymer matrices. The study established that reference unblended 100% brown coal ash geopolymer mortar samples yielded low strength, typically below 5MPa and poor durability. However, appropriate blends of brown coal ash with selected black coal fly ash (class F) and blast furnace slag to achieve target Si/Al ratios significantly enhanced both setting characteristics, as well as early age compressive strength development (25-35MPa) while improving overall durability performance compared to reference mixes. Moreover, lagoon fly ash blended geopolymer shows better durability while dry precipitator fails to perform well. The discussion also focuses on key source material parameters and reaction processes that influence compressive strength and durability behaviour of marginal brown coal ash sources during geopolymerisation reactions.

scholarly journals The potential use of pumice in mine backfill

2020 ◽  
Vol 1 ◽  
Author(s):  
Mohammed A. Hefni
Keyword(s):  
Compressive Strength ◽  
Portland Cement ◽  
Mining Industry ◽  
Strength Development ◽  
Natural Pozzolan ◽  
Mine Backfill ◽  
Natural Pozzolans ◽  
Cemented Backfill ◽  
Compressive Strength Development ◽  
Potential Use

Abstract The use of natural pozzolans in concrete applications is gaining more attention because of the associated environmental, economic, and technical benefits. In this study, reference cemented mine backfill samples were prepared using Portland cement, and experimental samples were prepared by partially replacing Portland cement with 10 or 20 wt.% fly ash as a byproduct (artificial) pozzolan or pumice as a natural pozzolan. Samples were cured for 7, 14, and 28 days to investigate uniaxial compressive strength development. Backfill samples containing 10 wt.% pumice had almost a similar compressive strength as reference samples. There is strong potential for pumice to be used in cemented backfill to minimize costs, improve backfill properties, and promote the sustainability of the mining industry.

scholarly journals Strength and Durability Performance of Alkali-Activated Rice Husk Ash Geopolymer Mortar

2014 ◽  
Vol 2014 ◽  
pp. 1-10 ◽  
Author(s):  
Yun Yong Kim ◽  
Byung-Jae Lee ◽  
Velu Saraswathy ◽  
Seung-Jun Kwon
Keyword(s):  
Compressive Strength ◽  
Rice Husk ◽  
Rice Husk Ash ◽  
Polymerization Reaction ◽  
Strength Development ◽  
Geopolymer Concrete ◽  
Portland Cement Concrete ◽  
Mix Proportion ◽  
Strength And Durability ◽  
Alkali Activated

This paper describes the experimental investigation carried out to develop the geopolymer concrete based on alkali-activated rice husk ash (RHA) by sodium hydroxide with sodium silicate. Effect on method of curing and concentration of NaOH on compressive strength as well as the optimum mix proportion of geopolymer mortar was investigated. It is possible to achieve compressive strengths of 31 N/mm2and 45 N/mm2, respectively for the 10 M alkali-activated geopolymer mortar after 7 and 28 days of casting when cured for 24 hours at 60°C. Results indicated that the increase in curing period and concentration of alkali activator increased the compressive strength. Durability studies were carried out in acid and sulfate media such as H2SO4, HCl, Na2SO4, and MgSO4environments and found that geopolymer concrete showed very less weight loss when compared to steam-cured mortar specimens. In addition, fluorescent optical microscopy and X-ray diffraction (XRD) studies have shown the formation of new peaks and enhanced the polymerization reaction which is responsible for strength development and hence RHA has great potential as a substitute for ordinary Portland cement concrete.

Sign in / Sign up

Export Citation Format

Share Document