• Proceedings of the Korean Institute of Building Construction Conference
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• 2013.11a
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• pp.190-191
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• 2013

In this research, the fundamental experiment for colour concrete(by using pigment) has been invested. Fundamental properties and dyeability for the colour mortar as the changing replacement ratio of pigment has been tested. For the conclusion, with the increasing ratio of pigment, the flow and compressive strength for the mortar has been decreased, For the dyeability, there's little difference when replacement ratio of dyestuff changed when the colour is red and yellow, but large difference when the blue pigment was used. Consider about the workability and strength of the mortar, the optimum pigment's replacement ratio is fixed as 2.5%.

• Journal of the Korea Concrete Institute
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• v.21 no.1
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• pp.55-64
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• 2009

This study is aimed to derive the optimum mix proportion of the combined self compacting concrete according to cement types (blast-furnace slag cement and belite cement) and to propose the basic data to field construction work after evaluating the quality properties. Specially, lime stone powder (LSP) as binder and viscosity agent are used in the combined self compacting concrete because slurry wall of an underground LNG storage tank should be kept stability of quality during concrete working. Replacement ratio of LSP is determined by confined water ratio test and main design factors including fine aggregate ratio ($S_r$), coarse aggregate ratio ($G_v$) and water-cement ratio (W/C) are selected. Also, quality properties including setting time, bleeding content, shortening depth and hydration heat on the optimum mix proportion of the combined self compacting concrete according to cement type are compared and analyzed. As test results, the optimum mix proportion of the combined self compacting concrete according to cement type is as followings. 1) Slag cement type-replacement ratio of LSP 13.5%, $S_r$ 47% and W/C 41%. 2) Belite cement type-replacement ratio of LSP 42.7%, Sr 43% and W/C 51%. But optimum coarse aggregate ratio is 53% regardless of cement types. Also, as test results regarding setting time, bleeding content, shortening depth and hydration heat of the combined self compacting concrete by cement type, belite cement type is most stable in the quality properties and is to apply the actual construction work.

• Journal of the Korean Geotechnical Society
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• v.16 no.4
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• pp.117-128
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• 2000

Sand compaction pile(SCP) is one of the ground improvement techniques which is being used for not only accelerating consolidation but also increasing bearing capacity of loose sands or soft clay grounds. In this study, laboratory model test and large-scale direct shear test were performed to investigate the effects of area replacement ratio of composite ground in order to find out the optimum value of area replacement ratio for the ground improvement purpose. Area replacement ratios of 20%, 30%, 40%, 50%, 60% were chosen respectively in the model tests to study the effects of area replacement ratio on variations of stress concentration ratio, settlement and shear strength characteristics of composite ground. In large-scale direct she4ar tests, area replacement ratios of 20%, 30%, 46% were applied to study their effects on shear strength characteristics of composite ground.

• Asian-Australasian Journal of Animal Sciences
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• v.25 no.2
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• pp.291-298
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• 2012

While attempting to develop low salt, low fat and high fibre chicken nuggets, the effect of partial (40%) common salt substitution and incorporation of chickpea hull flour (CHF) at three different levels viz., 5, 7.5 and 10% (Treatments) in pre-standardized low fat chicken nuggets (Control) were observed. Common salt replacement with salt substitute blend led to a significant decrease in pH, emulsion stability, moisture, ash, hardness, cohesiveness, gumminess and chewiness values while incorporation of CHF in low salt, low fat products resulted in decreased emulsion stability, cooking yield, moisture, protein, ash, color values, however dietary fibre and textural properties were increased (p<0.01). Lipid profile revealed a decrease in total cholesterol and glycolipid contents with the incorporation of CHF (p<0.01). All the sensory attributes except appearance and flavor, remained unaffected with salt replacement, while addition of CHF resulted in lower sensory scores (p<0.01). Among low salt, low fat chicken nuggets with CHF, incorporation CHF at 5% level was found optimum having sensory ratings close to very good. Thus most acceptable low salt, low fat and high fibre chicken nuggets could be developed by a salt replacement blend and addition of 5% CHF.

• Advances in concrete construction
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• v.13 no.3
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• pp.233-242
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• 2022

An attempt is made to develop an eco-friendly concrete with ground granulated blast furnace slag (GGBS) and pond ash as partial replacement materials for cement and fine aggregate, respectively without compromising the strength and durability. Sixteen concrete mixes were developed by replacing cement and fine aggregate by GGBS and pond ash, respectively in stages of 10%. The maximum replacement levels of cement and fine aggregates were 50% and 30% respectively. Experimental results revealed that the optimum percentage of GGBS and pond ash replacement levels were 30% and 20% respectively. The optimized mix was used further to study the flexural behavior and durability properties. Reinforced Concrete (RC) beams were cast and tested under a four-point bending configuration. Also, the specimens prepared from the optimized mix were subjected to alternate wet and dry cycles of acid (3.5% HCl and H₂SO₄) and sulphate (10% MgSO₄) solutions. Results show that the optimized concrete mix with GGBS and pond ash had a negligible weight loss and strength reduction.

• Proceedings of the Korea Water Resources Association Conference
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• 2021.06a
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• pp.145-145
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• 2021

Water distribution networks (WDNs) are designed to satisfy water requirement of an urban community. One of the central issues in human history is providing sufficient quality and quantity of water through WDNs. A WDN consists of a great number of pipelines with different ages, lengths, materials, and sizes in varying degrees of deterioration. The available annual budget for rehabilitation of these infrastructures only covers part of the network; thus it is important to manage the limited budget in the most cost-effective manner. In this study, a novel pipe replacement scheduling approach is proposed in order to smooth the annual investment time series based on a life cycle cost assessment. The proposed approach is applied to a real WDN currently operating in South Korea. The proposed scheduling plan considers both the annual budget limitation and the optimum investment on pipes' useful life. A non-dominated sorting genetic algorithm is used to solve a multi-objective optimization problem. Three decision-making objectives, including the minimum imposed LCC of the network, the minimum standard deviation of annual cost, and the minimum average age of the network, are considered to find optimal pipe replacement planning over long-term time period. The results indicate that the proposed scheduling structure provides efficient and cost-effective rehabilitation management of water network with consistent annual budget.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2010.05a
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• pp.981-982
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• 2010

• 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.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2006.05a
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• pp.19-22
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• 2006

The quantity of Recycled concrete powder is increased, because it hal been ever so often crushing for production of a good quality recycled aggregates This Study is on the Development of Concrete-Product by Using Recycled Concrete Powder and alto for know performance of concrete-producted having low water contents and it is to know for all of performance of concrete-producted having low water contents The conclusions of this study are following. The use of replacement cement is not effective, because it has strengh of less than 10MPa But It is possible to develop high strength concrete-producted having 39MPa above compressive strength by using recycled concrete powder. Because strength enhancement effects by recycled concrete powder are responsible to optimum grading. The conclusions of this study are following. The use of replacement cement is not effective, because it has strengh of less than 10MPa. It is possible to develop high strength concrete-producted having 39MPa above compressive strength by using recycled concrete powder. Because strength enhancement effects by recycled concrete powder are responsible to optimum grading.