• Geomechanics and Engineering
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• v.28 no.6
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• pp.547-557
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• 2022

Dune sands are poorly graded collapsible soils lacking fines. This experimental study explored the technical feasibility of sustainable invigoration of fine waste materials to improve the geotechnical properties of dune sand. The fine waste considered in this study is fine marble waste. The fine waste powder was mixed with dune sand at different contents (5, 10,15, 20, 25, 50%), where the gradation, void ratio, compaction, and shear strength characteristics were assessed for each fine marble waste -dune sand blend. The geotechnical properties of the dune sand-fine marble waste mix delineated in this study reveal the enhancement in compaction and gradation characteristics of dune sand. According to the results, the binary mixture of dune sand with 20% of fine marble waste gives the highest maximum dry density and results in shear strength improvement. In addition, a numerical study is conducted for the practical application of the binary mix in the field and tested for an isolated shallow foundation. The elemental analysis of the fine marble waste confirms that the material is non-contaminated and can be employed for engineering applications. Furthermore, the numerical study elucidated that the shallow surface replacement of the site with the dune sand mixed with 20% fine marble waste gives optimal performance in terms of stress generation and settlement behavior of an isolated footing. For a sustainable mechanical performance of the fine marble waste mixed sand, an optimum dose of 20% fine marble waste is recommended, and some correlations are proposed. Thus, for improving dune sand's geotechnical characteristics, the addition of fine marble waste to the dune sand is an environment-friendly solution.

• Proceedings of the Korea Concrete Institute Conference
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• 2004.05a
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• pp.376-379
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• 2004

The objective of in this study makes investigation into the characteristics of concrete as to properties and blended ratio of crushed aggregates through experimental researches. In this study, river sand is blended with crushed sand as to investigate the quality change and characteristics of concrete with variation of blend ratio of crushed sand(50, 60, 70, 80, 90, $100\%$). Measured the air contents and slump to investigate properties of fresh concrete, and unit weight and compressive strength in age of 7, 28days to investigate properties of hardened concrete. The experimental results of crushed aggregates' qualities were all satisfied with Korea Standard's values.

• Proceedings of the Korea Concrete Institute Conference
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• 2005.11a
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• pp.731-734
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• 2005

Crushed sand is blended in order to investigate the quality changes and characteristics of concrete with variation of blend ratio of crushed sand (50, 60, 70, 80, 90, $100\%$). Slump and air content were measured to investigate properties of fresh concrete, and unit weight, compressive strength and modulus of elasticity in age of 7, 28, 60, 90, 180 days were measured to investigate properties of hardened concrete. Compressive strength, unit weight and modulus of elasticity were increased as time goes by and they are expected to keep on increasing in long-term age as well. As a result of measuring compressive strength and modulus of elasticity in age of 7, 28, 60, 90, 180days, compressive strength was highest when it is $70\%$ of blended ratio.

• Proceedings of the Korea Concrete Institute Conference
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• 2005.05b
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• pp.429-432
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• 2005

An investigation for long-term strength characteristics of crushed sand concrete using crushed sands produced in Yang-san, Kim-hae and Jin-hae that can assume to respectively represent eastern, middle and western suburb of Busan was carried out. Cases were divided as variation of blend ratio of crushed sand (50, 60, 70, 80, 90, 100$\%$) and area. Compressive strength, unit weight and strain in age of 28, 60, 90, 180, 356 days were measured in each case. Compressive strength, unit weight and modulus of elasticity were increased as time goes by and they are expected to keep on increasing in long-term age as well.

• Fisheries and Aquatic Sciences
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• v.17 no.3
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• pp.291-298
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• 2014

We investigate the effects of cryoprotectant mixtures on the quality of sand lance surimi (SLS) during storage at $-30^{\circ}C$. We monitored freeze-induced denaturation of myofibrillar protein in SLS and examined the texture profile of SLS gel. Freeze-induced denaturation was assessed by evaluating SLS $Ca^{+2}$-ATPase activity. SLS gels prepared with sorbitol or sucrose and a mixture of both as cryoprotectant. Higher concentrations of cryoprotectants resulted in significantly higher residual SLS $Ca^{+2}$-ATPase activity at the same storage time (P < 0.05). Residual $Ca^{2+}$-ATPase activity of SLS prepared with sorbitol was higher than that of sucrose when cryoprotectant concentration and storage period were same. A blend of sorbitol and sucrose resulted in a stronger cryoprptective effect of SLS myofibrillar protein than did sorbitol or sucrose alone. The presence of a phosphate compound in SOP (3% sorbitol + 0.2% phosphate compound) resulted in higher SLS $Ca^{2+}$-ATPase activity than that of did 5% sorbitol. The hardness, brittleness, and elasticity values and a folding test of the SLS gels were significantly affected by cryoprotectant concentrations and the storage time. Preference scores and acceptance for texture in a sensory evaluation of the SLS gels increased with increasing sorbitol or sucrose concentration.

• Computers and Concrete
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• v.20 no.4
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• pp.461-468
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• 2017

With the increasing demand in the production of concrete, there is a need for adopting a feasible, economical and sustainable technique to fulfill practical requirements. Self-Compacting Concrete (SCC) is one such technique which addresses the concrete industry in providing eco-friendly and cost effective concrete. The objective of the present study is to develop a mix design for SCC with Crushed Rock Fines (CRF) as fine aggregate based on the plastic viscosity of the mix and validate the same for its fresh and hardened properties. Effect of plastic viscosity on the fresh and hardened properties of SCC is also addressed in the present study. SCC mixes are made with binary and ternary blends of Fly Ash (FA) and Ground Granulated Blast Slag (GGBS) with varying percentages as a partial replacement to Ordinary Portland Cement (OPC). The proposed mix design is validated successfully with the experimental investigations. The results obtained, indicated that the fresh properties are best achieved for SCC mix with ternary blend followed by binary blend with GGBS, Fly Ash and mix with pure OPC. It is also observed that the replacement of sand with 100% CRF resulted in a workable and cohesive mix.

• Magazine of the Korean Society of Agricultural Engineers
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• v.29 no.4
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• pp.132-141
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• 1987

The objective of the study was to obtain the compressive the tensile and the fleniril strengthes, thermal resistance, chemical resistance and fire resistance of the reclaimed plastic corcrete in order to investigate the feasibility as a new construction material This reclaimed plastic concrete is a compositive material which is composed of sand and blend of 50% of LDPE(Low density polyethylene) and 50% of HDPE (High density polyethylene) which are inexpensive and easy to reclaim. The results obtained in the study are summarized as follows: 1. As the binder content ranging from 20 to 40 % increase, the compresie, the splitting tensile and the flexural strengthes were increased. The compressive strenzth of the specimen tested was the highest and flexural strength the next and tensile strength the lowest 2. The compressive, the tensile and flexural strengthes of specimens made of fine sand were higher than those of coarse sand. The compressive, the tensile and the flexural strengthes of specimens made of high pressure molding were higher than those of low pressure molding. 3.In comparison with different additives, the specimens with carbon black was excellent and B. H. T. good and ferric oxide poor for thermal resistance. 4. In relationship between the flexural strength with varying temperature from -23$^{\circ}C$ to 80$^{\circ}C$. The flexural strengthes were decreared as temperature increased at 25 %, 30 % and 35 % of binder contents, respectively. Especially at 60$^{\circ}C$, the flexural strength was significantly decreased. 5. The decrement of flexural strengthes and the weight losses after 7 days immersion in acid or alkali solutions were not significant. 6. Fire resistance of the reclaimed plastic concrete was not significantly influenced by the contents of sand. However, the fire resistance of the reclaimed plastic concrete was depend upon melting and ignition properties of the binder itself. Therefore. a proper selection of the binder and the fire retardant are recommended in arder to improve fire resistance of the reclaimed plastic concrete.

• Advances in concrete construction
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• v.5 no.6
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• pp.671-683
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• 2017

Commonly used concrete in general, consists of cement, fine aggregate, coarse aggregate and water. Natural river sand is the most commonly used material as fine aggregate in concrete. One of the important requirements of concrete is that it should be durable under certain conditions of exposure. The durability of concrete is defined as its ability to resist weathering action, chemical attack or any other process of deterioration. Durable concrete will retain its original form, quality and serviceability when exposed to its environment. Deterioration can occur in various forms such as alkali aggregate expansion, freeze-thaw expansion, salt scaling by de-icing salts, shrinkage, attack on the reinforcement due to carbonation, sulphate attack on exposure to ground water, sea water attack and corrosion caused by salts. Addition of admixtures may control these effects. In this paper, an attempt has been made to replace part of fine aggregate by tailing material and part of cement by fly ash to improve the durability of concrete. The various durability tests performed were chemical attack tests such as sulphate attack, chloride attack and acid attack test and water absorption test. The concrete blend with 35% Tailing Material (TM) in place of river sand and 20% Fly Ash (FA) in place of OPC, has exhibited higher durability characteristics.

• Proceedings of the Korea Concrete Institute Conference
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• 2004.11a
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• pp.193-196
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• 2004

The objective of in this study makes investigation into the characteristics of concrete as to properties and blended ratio of crushed aggregates through experimental researches. In this research observed crushed quality characteristic of crushed aggregates that is produced in representative stony mountains of Busan suburbs (Yang-san, Kim-hea, Jin-hea). And wished to investigate the quality change and characteristics of concrete with variation of blend ratio of crushed sand(50, 60, 70, 80, 90, $100\%$). Measured the air contents and slump to investigate properties of fresh concrete, and unit weight and compressive strength in age of 7, 28, 60, 90 days to investigate properties of hardened concrete.

• Journal of the Korea Concrete Institute
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• v.17 no.4 s.88
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• pp.569-579
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• 2005

An investigation for long-term strength characteristics of crushed sand concrete using crushed sands produced in Yang-san, Kim-hae and Jin-hae that can be assumed to respectively represent eastern, middle and western suburbs of Busan has been carried out. Concrete is composed of 70~80% of aggregates in whole volume so the effect of aggregates quality to the characteristics of concrete is very important. Since 1980s, aggregates used in concrete have already been substituted crushed stone because of the exhaustion of natural gravel and sand. Crushed sand tends to increase in using quantity because of the prohibition of sea sand picking and deterioration of river sand. Crushed sand is blended with river sand in order to investigate the quality changes and characteristics of concrete as variation of blend ratio of crushed sand (n, 50, 70, 80, 90, 100%). Slump and air content were measured to investigate the properties of fresh concrete. Unit weight, compressive strength and modulus of elasticity in age of 7, 28, 60, n, 180 days were measured to investigate properties of hardened concrete. Compressive strength, unit weight and modulus of elasticity were increased with a passage of time and they are expected to keep on increasing in long-term age as well. The experimental results of the qualifies of crushed aggregates in each producing area, were all satisfied with Korea Standard. The results of the measurement of slump exposed that slump preferably decreased as mixing rate increased till 70~80% but it increased to mixing rate 70~80%. The air content was exposed that it decreased by micro filler phenomenon according to that crushed sand b)ended ratio increased. According to the result of measuring unit weight in age of 7, 28, 60, 90, 180days, it increased in accordance with that blended ratio of crushed aggregates increases. As a result of measuring compressive strength and modulus of elasticity in age of 7, 28, 50, 90, 180days, compressive strength was highest when it is 70% of blended ratio.