• Journal of the Korean Society of Environmental Restoration Technology
• /
• v.2 no.2
• /
• pp.62-69
• /
• 1999

This study was carried out to find out the capability of applying such materials as porous concrete, could be called environmentally friendly materials, for bringing vegetations. For verying the purpose of the experiments such materials as potland cement and slag cement, coarse aggravates(${\phi}25mm$, ${\phi}18mm$, ${\phi}13mm$) were mixed. In the voids of porous concrete peatmoss and chemical fertilizers were filled, and on the surface of concrete organic soils were adhered for seeding grasses. For testing compressive strength, pH, voids the 12($4mixed{\times}3times$) specimens were manufactured. As results, the compressive strength of porous concretes were from 59 to $267kg/cm^2$ depend on mixed ratios between cements and coarse aggregates. Voids of concrete were from 33% to 40% and the pH were varied pH 8-10.5. So the capability of planting vegetations was to be ascertained. The germination and growth of grasses were not good, but it could be found out that the capability of vegetations on the concretes. For generalizing these results and applying on the construction sites, it is necessary to verificate following studies for various conditions.

• Journal of the Korean Society of Environmental Restoration Technology
• /
• v.16 no.1
• /
• pp.17-25
• /
• 2013

The mechanical properties appeared at the concrete mixed with Polypropylene fiber($1kg/m^3$, $3kg/m^3$, $5kg/m^3$) are compared with normal concrete and wire mesh one and evaluated. Achieved slump test to search effect that PP fiber gets to workability, even if the mixing amount of fiber increases, confirmed that slump value is no change almost. The no difference can be caused by hard mixture, but because of the big softness of fiber there is no effect greatly up to PP fiber mixing amount $5kg/m^3$ even with soft mixture. Compressive strengths and flexural strengths of the concretes with PP fiber and without the fiber are appeared almost alike. If examine load resistance ability by PP fiber mixing amount increase, it could know that the increase of fiber mixing amount improves load resistance ability and the toughness index is increased. While normal concrete is broken at the same time with crack, fiber mixed concrete stand in flexure load continuously after crack occurrence. In compare with wire mesh embeded concrete, wire mesh mixed concrete stands in some degree in flexure load by wire mesh crack occurrence and the test piece was broken at the same time. But, it could know that the PP fiber mixed concrete resist continuously to flexure load in bigger displacement.

• Proceedings of the Korean Geotechical Society Conference
• /
• 2005.03a
• /
• pp.1390-1395
• /
• 2005

To analyze the effects of oyster shell particles, inserted in the self-hardening matrix such as cement paste, on strength, homogenization analysis using micro structure was used to estimate and assess the apparent elastic modulus of oyster shell particle. DIB modeling technique was used to represent of the micro structure of oyster shell mixed concrete. The results showed that the apparent elastic modulus of LOS (large oyster shell particle) was changed with the amount of LOS inserted. In particular, when the amount of LOS was 200% of the weight of cement, the apparent elastic modulus of LOS tended to decrease rapidly. This could mean that the strength of oyster shell mixed concrete is much affected by LOS inserted material in mixed ratio of 200%.

• Proceedings of the Korean Institute of Building Construction Conference
• /
• v.y2004m10
• /
• pp.55-58
• /
• 2004

This paper investigated the results of quality of concrete using mixed sand with grading adjustment in order to find out the applicability of fine aggregate with bad grading, According to test results, fluidity of concrete with fine level grading river sand was decreased while with coarse level grading crushed sand increased compared with that with medium level grading crushed sand. Use of mixed sand with grading adjustment(MSG) resulted in an improvement in fluidity. Increase in fineness modulus led to an increase in bleeding, For compressive strength, use of MSG increased compressive strength. For drying shrinkage, use of fine level grading river sand resulted in an increasing drying shrinkage due to the larger presence of fine particles, while use of MSG led to a reduction in drying shrinkage

• Proceedings of the Korean Institute of Building Construction Conference
• /
• 2017.05a
• /
• pp.204-205
• /
• 2017

In this study, flowability and strength on ultra high performance concrete(UHPC) pre-mixed binders with fiber was investigated. The flow of UHPC with pre-mixed binders was higher than that of seperate mixing conditions. The UHPC using PVA fiber with high specific surface area showed a low flow compared to steel fiber. An pre-mixing method led to improved strength of UHPC and low deviation of specimens due to dispersion effect of each materials.

• Magazine of the Korea Concrete Institute
• /
• v.3 no.4
• /
• pp.16-22
• /
• 1991

• Magazine of the Korea Concrete Institute
• /
• v.25 no.1
• /
• pp.25-28
• /
• 2013

• Magazine of the Korea Concrete Institute
• /
• v.5 no.3
• /
• pp.3-9
• /
• 1993

• Magazine of the Korea Concrete Institute
• /
• v.5 no.3
• /
• pp.10-18
• /
• 1993

• Magazine of the Korea Concrete Institute
• /
• v.5 no.3
• /
• pp.19-30
• /
• 1993