• Advances in concrete construction
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• v.8 no.1
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• pp.33-37
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• 2019

The present investigation is mainly focused on studying the flexural behavior of reinforced geopolymer concrete (RGPC) beams under pure bending. In this study, copper slag (CS) was used as a partial replacement of fine aggregate. Sand and CS were blended in different proportions (100:0, 80:20, 60:40 and 40:60) (sand:CS) by weight. Fly ash and ground granulated blast furnace slag (GGBS) were used as binders and combination of sodium hydroxide (8M) and sodium silicate solution were used for activating the binders. The reinforcement of RGPC beam was designed as per guidelines given in the IS 456-2000 and tested under pure bending (two-point loading) after 28 days of ambient curing. After conducting two point load test the flexural parameters viz., moment carrying capacity, ultimate load, service load, cracking moment, cracking load, crack pattern and ultimate deflection were studied. From the results, it is concluded that RGPC beams have shown better performance up to 60% of CS replacement.

• Proceedings of the Korea Concrete Institute Conference
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• 2001.05a
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• pp.683-688
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• 2001

In case of constructing the concrete structures under seawater environment, the concrete suffers from deterioration due to penetration of various ions such as chloride, sulfate and magnesium in seawater. Tn the present study, Immersion tests with artificial seawater were carried out to investigate the resistance to seawater attack of antiwashout underwater concrete. From the results of compressive strength, it was found that blended cement concrete due to mineral admixtures such as fly ash(FA) and ground granulated blast-furnace slag(SGC), were superior to ordinary portland cement concrete with respect to the resistance to seawater attack. Moreover, XRD analysis indicated that the formed reactants of ordinary portland cement paste by sulfate and magnesium ions led to the deterioration of concrete. As expected, however, the blended cements with FA or SGC have a good resistance to seawater attack. This paper would discuss the mechanism of seawater deterioration and benefical effects of antiwashout underwater concretes with mineral admixtures.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2014.05a
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• pp.132-133
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• 2014

In this study, high volume of industrial by-products including blast furnace slag, recycled aggregate powder and incineration ash have been utilized on the slurry of the foamed lightweight concrete. As to decrease the price of the lightweight foam concrete, mortar based slurry and concrete based slurry has been fixed. As the variation of the foam conduction ratio and aggregates, the foam ratio and compressive strength has been tested. Results showed that using recycled aggregates in the slurry showed better effect than using natural aggregates due to the alkali properties of the recycled aggregates could activate the potential hydraulic properties of the blast furnace slag. Consider about the low price of the recycled aggregates, it could be identified that using recycled aggregates in high volume blast furnace slag blended lightweight concrete showed better compressive strength than natural aggregates.

• Proceedings of the Korea Concrete Institute Conference
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• 1999.04a
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• pp.407-410
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• 1999

The 5 types of cement mortar was immersed in the various chemical solutions for 400 days and then the compressive strength and the length change were measured to consider the chemical resistance at required ages. Due to the effect of flyashe and GGBF slag, the compressive strength of blended cement mortar was higher than that of portland cement mortar at long ages. According to the result of length change, the mineral admixture in blended cement had an indluence on reducing the amount of C3A, the cause of making concrete expand, and it made the formation of cements mortar denser so that the length change was much smaller than that of the portland cement mortar. However, the OPC mortar immersed in Na2SO4 solution for 180 days shows 4 times bigger length change chante than the blended cement mortar.

• Proceedings of the Korea Concrete Institute Conference
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• 2009.05a
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• pp.343-344
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• 2009

Compressive strength and chloride ions permeability measurements of ternary blended cement concretes incorporating ground granulated blast-furnace slag and fly ash were performed From a result of this study, it was found that there may be not a linear relationship between compressive strength and durability of ternary blended cement concretes.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2011.11a
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• pp.55-56
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• 2011

This study is to investigate the engineering properties of low heat concrete incorporating improved ternary blended cement by combining OPC(original portland cement), blast furnace slag and fly ash. The results were summarized as following ; For ITB(Improved Ternary Blend)mixture was that setting time proved to be accelerated, and adiabatic temperature rises were low. The use of ITB resulted in an increase of initial compressive strength.

• Proceedings of the Korea Concrete Institute Conference
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• 2002.05a
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• pp.569-574
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• 2002

Generally, the limestone powder is known to have some advantages in rheology of fresh concrete, resistance of material separation, and enhancement of strength at early ages. Recently, great attention is being paid to limestone blended cements in the manufacture of concrete, especially in the countries of Europe. The purpose of the present study is to establish the mechanical and durable properties of concrete containing slag and limestone powder. In this paper, the chloride ion penetration test, rapid carbonation test and rapid freezing-thawing test is carried out to study durability of concrete with various content of limestone powder. Futhermore, the strength of concrete is evaluated with various ages.

• Proceedings of the Korea Concrete Institute Conference
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• 2010.05a
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• pp.477-478
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• 2010

Concretes with binary blends of Portland cement, silica fume, fly ash and ground granulated blast furnace slag were produce to investigate their effects on compressive strength and chloride transport in rapid chloride permeability. Ten different mix of concrete with 0.45 water/binder were produced. Portland cement was replacedby: (i) 10%, 20%, 30% Fly ash (ii) 3%, 5%, 10% Silica Fume (iii) 20%, 40%, 60% GGBS. Compressive strength of concrete with the pozzolans is higher compared to that of the Portland cement concrete. The test results indicate the fly ash, silica fume, and ground granulated furnace slag greatly reduce the rapid chloride permeability of concrete. It was concluded that pozzolans are more effective to reduce chloride permeability of concrete.

• Advances in concrete construction
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• v.3 no.1
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• pp.1-14
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• 2015

China accounts for nearly half of the global steel production. As a waste material or a by-product in the manufacture process, a large amount of blast furnace slag is generated every year. The majority of recycled blast furnace slag is used as an additive in low-grade blended cement in China (equivalent to the UK CEM II or CEM III depending on the slag content). The cost of using ground granulated blast furnace slag (GGBS) in such low-grade applications may not be entirely reimbursed based on market research. This paper reports an on-going project at Xi'an Jiaotong-Liverpool University (XJTLU) which investigates the feasibility of using GGBS in long-span concrete structures by avoiding/reducing the use of crack control reinforcement. Based on a case study investigation, with up to 50% of CEM I cement replaced with GGBS, a beneficiary effect of reduced thermal contraction is achieved in long-span concrete slabs with no significant detrimental effect on early-age strengths. It is believed that this finding may be transferable from China to other Asian countries with similar climates and economic/environmental concerns.

• Proceedings of the Korea Concrete Institute Conference
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• 2006.11a
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• pp.485-488
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• 2006

This research has evaluated flowability of ultra flowing self-compacting concrete, which is limitedly used for traditional building structures, in accordance with the first class regulations of Japan Society of Civil Engineering(JSCE) that can be applied to overcrowding-arrangement of bar, as a part of application methods that ultra flowing self-compacting concrete is applied to both precast and prestress bridge structures. The experimental results show that the flowability is acceptable in ternary blended among binary and ternary blended mixings, which satifies the first class regulation of JSCE. It is also concluded to use fly ash to increase viscosity of concrete in the case of segregation resistance because of low viscosity in the mixture of slag from blast furnace and limestone micropowder. Satisfying goals of every mixing after U-box self-compacting experiment, we conclude that ultra flowing self-compacting concrete is applicable to bridges and civil constructions of overcrowding arrangement of bar with evaluation of flowability of ultra flowing self-compacting concrete.