• 한국건축시공학회:학술대회논문집
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• 한국건축시공학회 2005년도 추계 학술논문 발표대회
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• pp.63-66
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• 2005

Recently, Trouble of sand supply is occurred according to exhaustion of natural sand resources. therefore, various measures are proposed for solution of trouble of sand supply also the government settled trouble of sand supply through application of crushed sand. but because both crushed sand are poor against general sand, they lead to lowering of qualify of ready-mixed concrete. Therefore, this study evaluated engineering property and durability of concrete using crushed sand and applied evaluation result to fundamental data for quality control of concrete using crushed sand. The results of this study have shown that quality of concrete using crushed sand independently is poor against general concrete. but, the workability, compressive strength and durability of concrete mixed crushed sand with genera can improve on those of concrete used general sand.

• 한국콘크리트학회:학술대회논문집
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• 한국콘크리트학회 1997년도 가을 학술발표회 논문집
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• pp.76-82
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• 1997

Recently as the development of a large-scale ocean structure or ocean is in progress, the importance of underwater concrete construction came to the fore. However, a problem with this underwater concrete construction is the segregation of cement and aggregate occurs when concrete is poured into the underwater. However, recently as an adhesiveness of the constituents of fresh concrete is increased even in our country, antiwashout concrete admixture were developed. The antiwashout concrete admixture can reduce the segregation significantly. Although this antiwashout underwater concrete is superior to the traditional underwater concrete in terms of durability, watertightness, stability, etc. But it is still unsatisfied due to the lack of criterion or construction experiences. Furthermore, because of an insufficiency of natural aggregate, the development of replacing aggregate came to be necessary. Accordingly, the purpose of this study is to investigate the feasibility of sea sand as a replacing aggregate and the characteristic change of antiwashout underwater concrete using river sand, sea sand, and blended sand (river sand:sea sand=3:7) through experimental researches.

• International Journal of Concrete Structures and Materials
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• 제6권4호
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• pp.231-237
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• 2012

Recently, it has been difficult to get natural sand for concrete due to an insufficient supply in Korea. Crushed sand was thought as a substitute and previous research has been focused on low fluidity and normal compressive strength (24-30 MPa). Study on high performance concrete using crushed sand is hardly found in Korea. In this study it was investigated that the effect of the crushed sand on fluidity and compressive strength properties of high performance concrete. Blending crushed sand (FM: 3.98) produced in Namyangju, Kyunggido and sea sand (FM: 2.80) produced in Asan bay in Chungnam. The final FMs of fine aggregate were 3.50, 3.23, and 3.08. W/B was set as 0.25 to get high performance. With the test results an analysis of relationship was performed using a statistical program. It was shown that strength property of concrete using crushed aggregate at the very early age or after specific time was mainly affected by strength development properties of binders instead of the crushed sand.

• 한국콘크리트학회:학술대회논문집
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• 한국콘크리트학회 2006년도 춘계 학술발표회 논문집(II)
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• pp.137-140
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• 2006

This study make an investigation into the quality of sand supplied with remicon manufacturing plant and examine concrete influenced by a source of supply of sand. As a result of the indoor test, the quality of crushed sand, EEZ sand and sand of north korea are worse than general sea sand. therefore, crushed sand, EEZ sand and sand of north sand lower quality of concrete.

• 한국콘크리트학회:학술대회논문집
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• 한국콘크리트학회 2006년도 춘계 학술발표회 논문집(II)
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• pp.629-632
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• 2006

This study investigated the engineering properties of crushed sand, based on improvement quality technology, and washed sand concrete by conducting mock-up test, in order to verify the availability of crushed sand for full sized structure. Test results showed that fluidity, air content, supersonic waves and corrosion state of concrete using crushed sand had favorable results. In addition, it is found that compressive strength, drying shrinkage length change, hydration heat and neutralization of crushed sand concrete exhibited similar tendency, with that of washed sand concrete. The crushed concrete using developed quality improvement technology shows comparable performance to washed sand concrete.

• 한국건설순환자원학회논문집
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• 제2권3호
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• pp.265-271
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• 2014

It is strongly needed to investigate the fine sand as an alternative fine aggregate of well-graded river sand because the fine sand which is being enormously distributed in the midstream and downstream of Nakdong-River in Korea has a poor grading but good quality as a fine aggregate for concrete. Thus, the purpose of this experimental research is to evaluate the durability of concrete using the fine sand to utilize it actively as a fine aggregate. For this purpose, the concrete specimens using different fine sand were made for the specified concrete strength of 35MPa, and then their durability such as the resistance to freezing and thawing and carbonation, and drying shrinkage were evaluated. It was observed from the test results that the resistance to freezing and thawing and carbonation of concrete using the fine sand was similar to that of concrete using reference sand, but the drying shrinkage of concrete using the fine sand with small fineness was comparatively lager than that of concrete using reference sand.

• Structural Engineering and Mechanics
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• 제53권6호
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• pp.1241-1251
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• 2015

Faced with the growing needs of material resources and requirements of environmental protection for achieving sustainable development, it has become necessary to study and investigate all possibilities of exploring crushed and dune sand, reusing industrial wastes and by-product, and also applying new technologies including sand concrete which can replace the conventional concretes in certain structures to surmount the deficit on construction materials, conserve natural resources, lessen the burden of pollutants to protect the environment and reduce the consumption of energy sources. This experimental study is a part of development and valorization of local materials project in Skikda region (East of Algeria). It aims at studying the effects of partial replacement of sand with marble waste as fines on several fresh and hardened properties of sand concrete in order to reuse these wastes in the concrete manufacturing, resolve the environmental problems caused by them and find another source of construction materials. To achieve these objectives, an experimental program has been carried out; it was consisted to incorporate different percentages of marble waste fines (2, 4, 6, 8, 10 and 12%) in the formulations of sand concrete and study the development of several mechanical and rheological properties. We are also trying to find the optimal percentage of marble waste fine replaced in sand concrete that makes the strength of the concrete maximum. Obtained results showed that marble waste fines improve the properties of sand concrete and can be used as an additive material in sand concrete formulation.

• 한국콘크리트학회:학술대회논문집
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• 한국콘크리트학회 2006년도 추계 학술발표회 논문집
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• pp.497-500
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• 2006

In this paper, study on applicability and quality control of the concrete using crushed sand. Recently, Trouble of sand supply is occurred according to exhaustion of natural sand resources. Now, application of crushed sand are proposed for solution of trouble of sand supply. Therefore, this study evaluated properties of concrete using crushed sand which mixing rate and changing FM.

• 한국콘크리트학회:학술대회논문집
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• 한국콘크리트학회 1992년도 가을 학술발표회 논문집
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• pp.31-36
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• 1992

This paper, an experimental study on the effect of mixed sand used sea and river as fine aggregate of concrete, is connected with the properties of fresh and hardended concrete and steel corrosion to investigate workability and engineering properties and general steel bar's corrosion of concrete used mixed sand. After analyzing positively fresh and hardenend concrete and ratio of the corrosion area affected by the autoclave cycle, the purpose of this paper is to provide an experimental data developing concrete used mixed sand.

• 한국콘크리트학회:학술대회논문집
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• 한국콘크리트학회 1997년도 가을 학술발표회 논문집
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• pp.83-88
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• 1997

In this paper, we described the basic elements (relative flowing area ratio and funeling velocity ratio in mortar, flowability and self-compactibility in concrete, and etc.) required for the maximum mix design of the super flowing concrete (SFC) using manufactured sand. Also, manufactured sand and fly ash were used for investigating characteristics of SFC through various experiments (replacement ratio of manufactured sand, optimum mix condition) before producing the concrete in batch plant. As the result of this project, the SFC using manufactured sand up to 50% showed high flowability and self-compactibility in fresh concrete. Furthermore, its compressive strength is higher than normal concrete without manufactured sand. From now on, this study may suggest how to apply manufactured sand in the SFC.