• International Journal of Concrete Structures and Materials
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• v.1 no.1
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• pp.57-61
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• 2007

This study investigated the mechanical and durability performance of roller-compacted concrete (RCC) with fly ash for dam applications. A test program studied the effects on the properties of fresh and hardened RCC with fly ash replacement ratio, as well as the long-term durability of the resulting mixture. Fly ash replaced 20, 30, 40, and 50% by mass of the cement. Laboratory tests of the compressive strength, splitting tensile strength, shear strength, chloride ion permeability, abrasion, and drying shrinkage were conducted. The test results demonstrated that 30% fly ash replacement is an optimum level, and that this mixture has excellent mechanical and durability properties.

• Proceedings of the Korea Concrete Institute Conference
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• 2000.04a
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• pp.66-71
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• 2000

Recently, great efforts and investment have been made in order to achieve economical production by applying new methods like minimization of man-power into construction field. Therefore in this study, we have been focused on the development and practical using of high of high flowing concrete with fly ash, superplasticizer and viscocity agent, also we find out the optimum mix proportions to accomplish good wuality high flowing concrete. The results of this study show that high flowing concrete with the ratio of fly ash replacement of 20%, viscosity agent of 300g/㎥ and superplsticizer 2.0%(C$\times$%) in W/B of 35, 45% has better performance than the high flowing concrete without fly ash replacement

• Journal of the Korea Organic Resources Recycling Association
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• v.27 no.1
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• pp.5-14
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• 2019

The objective of this study was investigated the effect of organic fertilizer(OF) application on the grain yield, protein content, and soil chemical properties in rice cultivation to evaluate the replacement ratio of OF based on basal fertilization of inorganic(nitrogen) fertilizer, In case of soil 1 with optimum range of organic matter for rice growth, the grain yield of rice in 70% and 100% treatments of OF were higher than the other treatments. In soil 2 with higher than the optimum range of soil organic matter, the grain yield of rice of NPK, 30%, 70%, 100%, and 300% treatments of OF showed no significant difference. When the protein criteria of rice quality was below 7%, the treatment of 30%, 70%, and 100% using OF in soil 1 were satisfied with protein criteria of rice. In case of soil 1, ammonium nitrogen content, electrical conductivity, and the organic matter in 30%, 70%, 100%, 300% treatments of OF showed similar tendency to NPK treatment. These results suggested that the substitution ratio of OF 70~100% could be appropriate to increase the yield and commercial quality for rice.

• Advances in concrete construction
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• v.6 no.2
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• pp.103-121
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• 2018

This paper reports the effects of coarse and fine recycled concrete aggregates (RCA) on fresh and hardened properties of self-compacting concrete (SCC) containing ground granulated blast-furnace slag (GGBFS) as cement replacement. For this purpose, three SCC mixes groups, were produced at a constant water to binder ratio of 0.38. Both fine and coarse recycled aggregates were used as natural aggregates (NA) replacement at different substitution levels of 0%, 25%, 50%, 75% and 100% by volume for each mix group. Each group, included 0, 15% or 30% GGBFS as Portland cement replacement by weight. The SCC properties investigated were self-compactability parameters (i.e., slump flow, T500 time, V-funnel flow time, L-box passing ability and sieve stability), compressive strength, capillary water absorption and water penetration depth. The results show that the combined use of RCA with GGBFS had a significant effect on fresh and hardened SCC mixes. The addition of both fine and coarse recycled aggregates as a substitution up to 50% of natural aggregates enhance the workability of SCC mixes, whereas the addition from 50 to 100% decreases the workability, whatever the slag content used as cement replacement. An enhancement of workability of SCC mixes with recycled aggregates was noticed as increasing GGBFS from 0 to 30%. RCA content of 25% to 50% as NA replacement and cement replacement of 15% GGBFS seems to be the optimum level to produce satisfactory SCC without any bleeding or segregation. Furthermore, the addition of slag to recycled concrete aggregates of SCC mixes reduces strength losses at the long term (56 and 90 days). However, a decrease in the capillary water absorption and water permeability depth was noticed, when using RCA mixes with slag.

• Asian-Australasian Journal of Animal Sciences
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• v.23 no.12
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• pp.1626-1631
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• 2010

An experiment was conducted to evaluate the effect of dietary replacement of normal maize (NM) with quality protein maize (QPM) on performance, immune response and carcass characteristics of broiler (Krishibro) chickens. Six experimental diets were prepared separately for starter and finisher phases. Diet 1 was a control diet formulated with NM and soybean meal. In diets 2-5, the NM was replaced with QPM at 25, 50, 75 and 100%, respectively. Diet 6 was the same as the control diet, but supplemented with synthetic lysine similar to the industry standard. Each test diet was fed to 8 replicates, each of 5 chicks, reared in stainless steel battery brooders. The AME content of QPM (3382 kcal/kg) was similar to that of NM (3,352 kcal/kg), but protein (9.91 vs. 8.94%), lysine (0.40 vs. 0.26%) and tryptophan (0.09 vs. 0.07%) contents of QPM were higher than NM. Dietary replacement of NM with 50% QPM significantly (p<0.05) improved body weight gain, feed conversion ratio, humoral immune response, relative bursa weight, and breast muscle yield and lowered abdominal fat content. No further improvement in these parameters was recorded by increasing the level of replacement of NM with QPM to either 75% or 100%. Further, the improvement noticed in the 50% QPM group was similar to the group fed the NM diet with lysine supplementation, and thus dietary replacement of NM with QPM at 50% did not need extra synthetic lysine supplementation. It is concluded that dietary replacement of NM with QPM at the 50% level resulted in optimum performance, higher breast muscle yield and higher immune response in broiler chickens.

• Advances in concrete construction
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• v.5 no.1
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• pp.31-48
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• 2017

Supplementary cementitious materials (SCM) have turned out to be a vital portion of extraordinary strength and performance concrete. Metakaolin (MK) is one of SCM material is acquired by calcinations of kaolinite. Universally utilised as pozzolanic material in concrete to enhance mechanical and durability properties. This study investigates the fresh and hardened properties of conventional concrete (CC) and self compacting concrete (SCC) by partially replacing cement with MK in diverse percentages. In CC and SCC, partial replacement of cement with MK varies from 5-20%. Fresh concrete properties of CC are conducted by slump test and compaction factor tests and for SCC, slump flow, T500, J-Ring, L-Box, V-Funnel and U-Box tests. Hardened concrete characteristics are investigated by compressive, split tensile and flexural strengths at age of 7, 28 and 90 days of curing under water. Carbonation depth, water absorption and density of MK based CC and SCC was also computed. Fresh concrete test results indicated that increase in MK replacement increases workability of concrete in a constant w/b ratio. Also, outcomes reveal that concrete integrating MK had greater compressive, flexural and split tensile strengths. Optimum replacement level of MK for cement was 10%, which increased mechanical properties and robustness properties of concrete.

• Proceedings of the Korea Concrete Institute Conference
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• 2002.10a
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• pp.11-16
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• 2002

The production of Portland cement involves maximum use of resources and energy, which leads to destruction of tile ecological environment, raising in serious environmental issues such as acid rain and the greenhouse effect. In order to combat the arising problems associated with Portland cement, it thus is necessary that a non-clinker cement should be developed. In this study, non-clinker cement is produced by blending granulate blast furnace slag with phosphogypsum as main materials, and small amounts of hydrate lime or waste lime as activators. This paper aims to investigate compressive strength according to various condition of mixing ratio, blame, W/C ratio and curing temperature. Compressive strength of non-clinker cement increases continuously according to increase in curing age and blain. Although the compressive strength is fairly comparable to that of OPC in the early curing age, it reaches a higher lever in the later age than that of OPC due to the optimum mixing ratio and the continuous reaction of slag and phosphogypsum. Results obtained from this study have shown that non-clinker cement could be used as a replacement of OPC.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2014.05a
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• pp.270-271
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• 2014

In this study, a replacement ratio of blast furnace slag coarse aggregate and a water binder ratio by an optimum combination of PHC file was investigated. As a results, the target strength 78.5MPa was altogether satisfied in a mix proportion 28-G100-SG0 and W/B ratio 26 %. The surface rupture was generated in 28-G0-SG100 combination after curing with the autoclave. According to the result of measuring the ingredient, the majority were the MgOH2 hydrate.

• Asian-Australasian Journal of Animal Sciences
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• v.31 no.11
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• pp.1795-1806
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• 2018

Objective: The study was designed to establish choline deficiency model (CDM) in broilers for evaluating efficacy of polyherbal formulation (PHF) in comparison with synthetic choline chloride (SCC). Methods: A total of 2,550 one-day-old Cobb 430 broiler chicks were randomly assigned to different groups in three experiments. In experiment 1, G1 and G2 served as normal controls and were fed a basal diet with 100% soybean meal (SBM) as a major protein source supplemented with and without SCC, respectively. In G3, G4, G5, and G6 groups, SBM was replaced at 25%, 50%, 75%, and 100% by soy protein isolate (SPI) to induce a graded level of choline deficiency. In experiment 2, PHF (500 and 1,000 g/ton) in comparison with SCC (1,000 g/ton) were evaluated. In experiment 3, dose-response of PHF (200, 400, and 500 g/ton) with SCC (400 g/ton) was determined. Results: Replacement of SBM by SPI produced a linear decrease in body weight gain (BWG) with a poor feed conversion ratio (FCR). 25% SBM replacement by SPI yielded an optimum negative impact on BWG and FCR; hence, it is considered for further studies. In experiment 2, PHF (500 and 1,000 g/ton) and SCC (1,000 g/ton) showed a similar performance in BWG, FCR and relative liver weight. In experiment 3, PHF produced an optimum efficacy at 400 g/ton and was comparable to SCC in the restoration of serum aspartate aminotransferase activity, abdominal fat, breast muscle lipid content and liver histopathological abnormalities. Conclusion: Replacement of SBM by SPI caused choline deficiency characterised by worsening of BWG, FCR, elevation in liver enzymes and histopathological changes indicating fatty liver. CDM was found valid for evaluating SCC and PHF. It is concluded that PHF has the potential to mimic biological activities of SCC through the restoration of negative effects caused by CDM.

• Proceedings of the Korea Concrete Institute Conference
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• 1996.10a
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• pp.266-270
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• 1996

The objective of this study is to develop the Non-compacting concrete with mormal strength in practice by using viscosity agent and flyash. In this paper, we present the reference data about not only the properties of Non-compacting concrete at fresh state such as flowability, segregation-resistibility, placebility and so on but, optimum mixing design using viscosity agent and flyash. The test results indicate that optimum dosage of viscosity agent in combination of flyash in 50% of W/C is about 400g/$\textrm{m}^3$ with 20% of the ratio of flyash replacement.