• Proceedings of the Korean Institute of Building Construction Conference
• /
• 2017.05a
• /
• pp.162-163
• /
• 2017

This study investigated the properties of lightweight foamed concrete by using synthetic foaming agent and artificial lightweight aggregate. The effects of artificial lightweight sizes on the compressive strength, density and pore structure of the concrete were investigated. The samples were assessed by MIP analysis and simultaneous SEM was used to study their pore distribution. This study showed the improvement of important properties of lightweight foamed concrete. Lower pore distribution and correspondingly higher compressive strength values were reached. This is for the purpose of providing basic data for the use of lightweight foamed concrete through improvement on the problem such as unstability, falling in fluidity and the strength of existed foaming agent.

• Proceedings of the Korean Institute of Building Construction Conference
• /
• 2012.05a
• /
• pp.89-90
• /
• 2012

This study analyzed and compared the flowing and strength properties of mortar depending on the different fine aggregate replacement ratios and whether or not the mixing of PVA fiber was applied. blast furnace slag, red mud, and silica fume that are industrial by-products were used for the analysis. The findings showed that higher replacement level of fine aggregate increased air content while decreasing the table flow. In addition, in case of the compressive strength, Plain mortar and PVA fiber with the replacement ratios of 15% and 30%, respectively showed the greatest strength development.

• Magazine of the Korean Society of Agricultural Engineers
• /
• v.45 no.1
• /
• pp.74-82
• /
• 2003

In this paper, an experimental program was undertaken to test the analysis on Component and mechanical characteristics for crushed stone of excavated Rocks from Sandstone, Shale, Mudstone, for use as a new source of aggregate. Physical and mechanical properties, required for aggregate materials, of major constituents of rock wastes including Sandstone, Shale, Mudstone, Felsite, Basalt, Marl were measured in the laboratory Test results showed that the Shale, Felsite, Basalt tested in this study might possibly be used for construction aggregates. In case of Sandstone and Mudstone, some physical properties such as rock strength were generally adoptable but the aggregate characteristics were lower than required.

• Journal of The Korean Society of Agricultural Engineers
• /
• v.55 no.3
• /
• pp.25-33
• /
• 2013

In this study, the optimum mix proportions of rain garden structure concrete were decided and the mechanical properties were evaluated. Experimental parameters were blast furnace slag, hwang-toh, recycled aggregates and natural jute fibers. The target compressive strength and chloride ion penetration were more than 24 MPa and less than 1000 coulombs, respectively. The response surface method was used for statistical optimization of experimental results. The optimal mixing ratios of the blast furnace slag, hwang-toh, recycled coarse aggregate and jute fiber volume fraction were determined 59.98 %, 8.74 %, 12.12 % and 0.2 %, respectively. The compressive strength, flexural strength and chloride ion penetration test results of optimum mix ratio showed that the 24.56 MPa, 3.88 MPa and 999.08 columbs, respectively.

• Journal of the Korea Institute of Building Construction
• /
• v.2 no.3
• /
• pp.115-121
• /
• 2002

The purpose of this study is investigating characteristics of paper-ash mortar according to partial replacement of fine aggregate by Paper-ash. For this purpose, selected test variables were mixing ratio with two levels of mortar(1:2, 1:3), and 3 types of paper-ash(A, B, C), and paper-ash content with four levels(5%,, 10%, 15%, 20%). As a result of this study, in all mixes with partial replacement of fine aggregate by Paper-ash generally Produced Paper-ash mortar with decreased compressive strength at ail age as compared to ordinary mixes. The mixing rate 1:2 was the higher increasing rate of strength than the mixing rate 1:3. The flow value and unit weight of paper-ash mortar were decreased with increasing of the paper-ash content. And the thermal conductivity of the thermal conductivity of the paper-ash mortar was lower than normal mixing without paper-ash.

• KSBB Journal
• /
• v.5 no.4
• /
• pp.347-353
• /
• 1990

The effects of nutrients and cell aggregate size on the cell growth of D. carota and the biosynthesi of carotenoid were investigated. Highest carotenoid content was obtained with sucrose as a carbon source and the equal ratio of ammonium to nitrate. High phosphate concentration stimulated the carotenoid biosynthesis in D. corota. 2,4-D inhibited the cell growth but stimulated the specific carotenoid content at high concentration. By modifying the medium composition based on these findings, three times higher specific carotenoid content and 2.5 times higher total carotenoid content were obtained as compared with the results obtained with basic MS media. Biosynthesis of carotenoid was found to be affected by cell aggregate size; high carotenoid production was obtained from the large aggregated cells resulted from high sucrose concentration.

• Proceedings of the Korean Institute of Building Construction Conference
• /
• 2018.05a
• /
• pp.326-327
• /
• 2018

It is expected that the proportion of crushed aggregate will increase in order to fill the decreasing supply of sea sand in the southeast area. However, it is necessary to supply the least amount of sea sand to diversify the aggregate source, in order to minimize the mixing ratio of sea sand and crushed sand to minimize the structural stability of the concrete.

• Proceedings of the Korean Geotechical Society Conference
• /
• 2008.10a
• /
• pp.1193-1198
• /
• 2008

Shaking table tests were performed to investigate the response of liquefaction mitigation of rammed aggregate piers(RAP) on soft ground. The displacements of the soft ground reinforced by RAP under area replacement ratio 7, 14, 28% during seismic loading were measured. The result of tests showed that effects of liquefaction mitigation were affected various area replacement ratios and ground acceleration on RAP systems.

• Proceedings of the Korean Institute of Building Construction Conference
• /
• 2019.05a
• /
• pp.215-216
• /
• 2019

Recently, due to abnormal climate phenomena caused by greenhouse gas, flood damage such as local torrential rain has been emerging in Korea. Accordingly, there is a growing need for porous blocks capable of permeability in concrete, but there are limitations in commercialization due to problems such as high unit weight and flexural strength development limitations. This study investigates the unit weight and strength properties of porous blocks using bottom ash as an alternative to aggregate as part of a study to improve the light weight of porous blocks.

• Proceedings of the Korean Institute of Building Construction Conference
• /
• 2019.11a
• /
• pp.79-80
• /
• 2019

This study was intended to examine the possibility of reducing hydration heat by FA substitution and combination of slag (CGS) from coal gasification power generation (IGCC) with mixed aggregate for concrete. The analysis results showed good results if liquidity increases as the ratio of CGS increases, air volume decreases, and compressive strength is mixed up to 25% in the residual aggregate. The results showed that the heat of hydration was reduced compared to plain due to the boron content of CGS as the CGS substitution rate increased, but it was larger due to the combination with FA substitution. It was found that the heat of hydration was reduced.