• 한국콘크리트학회:학술대회논문집
• /
• 한국콘크리트학회 1995년도 가을 학술발표회 논문집
• /
• pp.84-88
• /
• 1995

The results of an experimental study on manufacture and mechanical properties of concrete utilizing crushed sand and fly ash for construction materials are presented in theis paper. As the results show, the workability, compressive strength and freezing-thaw resistance were improved by proper contents of fly ash, replaced crushed sand, and air entraining agent. And the drying shinkage was decreased by proper contents of those. Also, the suitable weight contents of replacing ratio of crushed sand and weight ratio fly ash in concrete using crushed sand were in range of 30% and 15% respectively.

• 한국콘크리트학회:학술대회논문집
• /
• 한국콘크리트학회 2006년도 춘계 학술발표회 논문집(II)
• /
• pp.137-140
• /
• 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
• /
• 한국콘크리트학회 2001년도 가을 학술발표회 논문집
• /
• pp.417-422
• /
• 2001

The purpose of this study is to investigate experimentally the workability, compressive and flexural strength properties of rapid-set concrete with various mixture. The kinds of fine aggregate(river sand, sea sand, crushed sand), water-cement ratio(40%, 45%, 50%), sand-aggrega to ratio(33%, 36%, 39%) were chosen as the experimental parameters. Test variables are temperature of concrete, slump, air contents, compressive and flexural strength. The compressive and flexural strength for 3 hours and 6 hours were tested. As result, it was shown that temperature of concrete involved 45$^{\circ}C$, some time later decreased. The workability were decreasing in steps as the sand-aggregate ratio increased and crushed sand was the highest value. Higher compressive and flexural strength was shown following the order of river sand, sea sand, crushed sand regardless of sand-aggregate ratio. But the values of gap was just a little.

• 콘크리트학회지
• /
• 제7권4호
• /
• pp.129-136
• /
• 1995

이 연구는 쐐기쪼갬시험법에 의하여 강모래 콘크리트의 파괴에너지와 부순모래 콘크리트의 파괴에너지 측정을 통하여 콘크리트 강도와 파괴에너지 관계에 대하여 규명하였다. 그리고 부순모래 콘크리트의 파괴에너지와 강모래 콘크리트의 파괴에너지를 비교 검토하엿으며, 콘크리트의 특성길이도 구하였다. 이연구의 실험결과에 의하면 부순모래 콘크리트는 파괴특성 관점에서 강모래 콘크리트와 유사한 경향을 나타내고 있다. 그리고 압축강도가 20~60 MPa에서는 압축강도가 증가함에 따라 파괴에너지가 증가하였지만, 60 MPa이상의 범위에서는 압축강도가 증가하여도 파괴에너지는 증가하지 않았다.

• 한국콘크리트학회:학술대회논문집
• /
• 한국콘크리트학회 2005년도 추계 학술발표회 제17권2호
• /
• pp.623-626
• /
• 2005

This study is aimed for investigating the influence of the properties of crushed stone sand on the mixing factor and compressive strength of concrete. The results of this study are as follows; The influence of Particle Shape and Very Fine Sand(VFS) of crushed stone sand on the mixing factor was higher than Fineness Modulus. The demand water of concrete with crushed stone sand was decreased about $12\~18kg/m^3$with increasing $4\%$ of Particle Shape and increased $8\~15kg/m^3$ with increasing $3\%$ of ratio of Very Fine Sand(VFS).

• 한국콘크리트학회:학술대회논문집
• /
• 한국콘크리트학회 2003년도 가을 학술발표회 논문집
• /
• pp.533-536
• /
• 2003

The objective of in this study makes investigation into the characteristics of antiwashout underwater concrete as to mix proportion, casting and curing water through experimental researches. in this study, sea sand is blended with river sand, crushed sand is blended with river sand and sea sand as to investigate the quality change and characteristics of antiwashout underwater concrete with variation of blend ratio of sea sand and crushed sand(0, 20, 40, 60, 80, 100%). Higher compressive strength is measured following the order of river sand, sea sand, crushed sand regardless of age and casting condition. Except for case of using river sand, blended ratio of 40% is appeared on most compressive strength.

• 한국콘크리트학회:학술대회논문집
• /
• 한국콘크리트학회 2006년도 춘계 학술발표회 논문집(II)
• /
• pp.81-84
• /
• 2006

Currently, natural aggregates of good quality are hard to use because of continuous decrease of internal aggregate resource and regulation of gathering. So, use of crushed sand was being increased. On the other hand, skyscraper projects with 100 stories are being planned within the country and high strength concrete must be used to construct a skyscraper with 100 stories. High strength concrete is necessary to use crushed sand too because we are still unable to secure natural aggregates of good quality. So, This study indicated basic data necessary for mix design of high strength concrete through valuation of concrete property by quality variation of crushed sand.

• 한국콘크리트학회:학술대회논문집
• /
• 한국콘크리트학회 1998년도 봄 학술발표회논문집(II)
• /
• pp.661-664
• /
• 1998

In this paper, the properties of inter-lacking block by the kind of aggregate and fineness modulus are investigated. According to the experimental results, compressive strength and flexural strength increase and absorption ratio decrease with larger fineness modulus in the range of 2.15~4.20. Flexural strength with river sand is higher than that with crushed sand by about 19%, compressive strength with river sand, that with crushed sand by about 11% and absorption ratio with river sand is smaller than that with crushed sand by abort 2%.

• 한국콘크리트학회:학술대회논문집
• /
• 한국콘크리트학회 2006년도 추계 학술발표회 논문집
• /
• pp.437-440
• /
• 2006

Generally, the strength of concrete depends on factors of materials, mix proportions, compaction, manufacturing methods and curing and so on. And recently, it has increased the using of crushed sand for concrete due to the exhaustion of good natural aggregate. This is an experimental study to compare and analyze the fluidity and compressive strength of ultra-high strength concrete according to the replacement ratio of crushed sand. For this purpose, the mix proportions of concrete according to the W/B ratio and replacement ratio of crushed sand was selected. And then air content, slump-flow, O-lot, compressive strength test were performed.

• 한국콘크리트학회:학술대회논문집
• /
• 한국콘크리트학회 2006년도 춘계 학술발표회 논문집(II)
• /
• pp.141-144
• /
• 2006

In this study, evaluation of physical and chemical properties of crushed sand was performed to establish optimal mix proportion standard for concrete using crushed sand afterward. Most of properties of crushed sand were satisfied with KS F 2527. Especially, chemical stabilities such as alkali-aggregate reaction were fairly good. However, considerable attention would be required in using crushed sand from lime stone judging from the result that weight loss of it was more than 23.8%. There were some differences in the properties with production region, stone type and capacity of facility, therefore it is thought that quality should be controled by optimal regulations for corresponding items.