• Journal of the Korean Recycled Construction Resources Institute
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• v.5 no.2
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• pp.83-90
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• 2010

As a reinforced fabric, asbestos has been utilized as a fire-resistant material as it has a superior flexural stiffness and heat resistance up to $1500^{\circ}C$. However, due to its harmfulness, its use has been prohibited recently and the even the installed asbestos materials are being repaired or supplemented if there is a concern about flying. Asbestos is mainly used for construction panels as a reinforced fabric and coating materials to ensure the fire-resistance of steel frames. Asbestos was used as fire-resistant materials for steel frames until 1991 and then prohibited as Act on Industrial Safety and Health limits the concentration of asbestos in the air. Classified as a designated waste according to Act on Waste Control, asbestos must be buried if there is no possibility of flying (panel-type materials) or cement-solidified and then buried if there is a possibility of flying (spray coating material) In general, it is required that a new waste landfill include a certain landfill facility for designated waste, but in reality there is an absolute storage of landfill facilities for designated waste as they only install facilities of the size required by the regulations. This could result in the 2nd environmental pollution as they cannot process asbestos wastes which will be generated in large volume in the future. This study explores a method that melts asbestos wastes at $700^{\circ}C$ rather than cement-solidifying the waste asbestos from construction sites, especially asbestos-containing spray coating. The study results showed that there was no change in the composition and shape even though asbestos wastes was melted at $1300^{\circ}C$, but there was a change for the specimen which was process in advance for low temperature melting and then melt at $900^{\circ}C$.

• Tribology and Lubricants
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• v.19 no.2
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• pp.94-101
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• 2003

Used motor oil contains pollutants, including organic chemicals and meta]s. When disposed of improperly - in the trash, on the ground or in a sewer system - the pollutants may reach rivers, lakes or the ground water. Thus, all the waste oil products such as waste motor oil, waste oil container, and waste oil filter should be collected and transported for recycling or disposal by waste oil regulations. Because waste oil container is a valuable resource, waste oil containers can be reused, cleaned, buried, and burned for recycling processes. This paper presents the integrated management system that may increase the efficiency and productivity for collecting and reprocessing waste oil containers such as steel can and plastic container. The integrated management system consists of collection and transportation process management system and confirmation and certification process management system for waste oil containers.

• Proceedings of the Korean Society of Soil and Groundwater Environment Conference
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• 2004.09a
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• pp.377-380
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• 2004

To identify the effect of landfill waste for groundwater and unsaturated air environment, soil gas survey and hydrogeochemical study were executed. The geology of the study area is granite and aquifer is mainly composed of sandy soil. The results of spatial distribution from soil gas showed the boundary of buried waste and processes and degree of waste decomposition. Groundwater contamination by leachate from landfill is controlled by groundwater flow attributed by the original topography and liner.

• Journal of the Korean Geosynthetics Society
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• v.19 no.4
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• pp.33-40
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• 2020

It is now common to find the wastes buried in the past during the excavation process of soil for large scale housing and land development. Without proper treatment of the wastes environmentally, the excavation process is no longer able to proceed, and an action plan should be provided to treat the wastes with environmental and economic viability. In the study, the relationship between the apparent density of the wastes and the volume conversion factor, which is the basis in the estimation of waste treatment cost was investigated. From 10 sampling points of a landfill site, wastes were sampled, analyzed for physical characteristics, and the apparent density of mixed and sorted waste was assessed. Applying the empirical formula, and the formula we suggested here, the volume conversion factors were compared with that measured directly in the field using dump truck and excavator. Obviously there was a close relationship among the volume conversion factors resulting from the empirical formula, the formula we suggested and that measured in the field.

• Journal of the Korean Geotechnical Society
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• v.15 no.6
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• pp.99-109
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• 1999

In the case of domestic general waste landfills, cumulated leachate level is often formed in the landfill due to the waste of high moisture content and it becomes important to characterize the hydraulic properties of the disposed waste. Although many hydrologic studies have been peformed for leachate barriers and pheriperal subsurface environments, few studies have been done to investigate the hydraulic property of the disposed waste and cover soils and to analyse the leachate flow behavior within landfills. In this paper, the geotechnical properties of the waste and buried cover soils are identified through the field experiment including pumping and slug tests. The results of various tests show that the field density of the cover soils is somewhat higher than the maximum laboratory density of cover soils and the vertical flow of leachate and gas in the landfill is prevented by the buried cover soils. The hydraulic conductivities of field pumping test and slug tests are well matched and stayed in the range of hydraulic conductivities of well compacted wastes in the literature.

• Proceedings of the Korean Society of Soil and Groundwater Environment Conference
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• 2001.04a
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• pp.210-213
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• 2001

There has been a steady increase in treatment of wastes buried in unplanned waste landfill situated in urban area and river side. This study was carried out to evaluate the geotechnical and environmental properties of soil sorted by classifier from wastes in unregulated landfill. The physical mechanical, and environmental properties of sorted soil were investigated for treatment of wastes and soil including landfill.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2015.11a
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• pp.49-50
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• 2015

Recently, by-products from concrete industry are generated in large quantities because of urban redevelopment. Accordingly, waste concrete powder(WCP) inevitably generated in the course of crushing, screening, and separating the waste concrete also show high emission and be increasing gradually, but which is mostly buried with waste concrete aggregate. This is a basic research to increase the value added utilization rate of WCP. We have examined strength characteristic of extruding panel with WCP, depending on the curing methods. The result of study shows similar strength to the base specimen in autoclave curing condition. And in autoclave curing condition, the specimen with WCP of 20% and 30% satisfy the target strength of 14MPa.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2016.05a
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• pp.55-56
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• 2016

In the recent concrete industry, when producing recycled aggregates, waste concrete powder is by-produced in large quantities; however, since it is not used properly but buried or discarded. This study is to apply the waste concrete powder to a cement extruding panel as filler. Flexural strength and microstructure characteristics of panel is tested in order to improve the economics of the extruding panel. As a results of this study, it was found that extruding panel replacing silica(No.8) as the waste concrete powder totally showed little difference in the strength and satisfied the target flexural strength of 14MPa, comparing with controlled panel. In addition, we can understand that rich Portlandite and Calcite contributed to develop the strength in all curing conditions from XRD pattern.

• International Journal of Highway Engineering
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• v.15 no.2
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• pp.105-112
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• 2013

PURPOSES : Compared to the criteria from advanced countries, Korea has conservative criteria for the buried depth of pipeline (about 30~70cm deeper) causing the waste of cost and time. Therefore, this research investigated the effect of various buried depths of pipeline on pavement performance in order to modify the criteria to be safe but economical. In addition, a recycled aggregate which is effective in economical and environmental aspect was evaluated to be used as a refilling material. METHODS : In this study, total 10 pilot sections which are composed with various combinations of pavement structure, buried depth of pipeline, and refilling material were constructed and the telecom cable was utilized as a buried pipeline. During construction, LFWD (Light Falling Weight Deflectometer) tests were conducted on each layer to measure the structural capacity of underlying layers. After the construction is completed, FWD (Falling Weight Deflectometer) tests and moving load tests were performed on top of the asphalt pavement surface. RESULTS : It was found from the LFWD and FWD test results that as the buried depth decrease, the deflections in subbase and surface layer were increased by 30% and 5~10%, respectively, but the deflection in base layer remained the same. In the moving load test, the longitudinal maximum strain was increased by 30% for 120mm of buried depth case and 5% for 100mm of buried depth case. Regarding the effect of refilling material, it was observed that the deflections in subbase and surface layer were 10% lager in recycled aggregate compared to the sand material. CONCLUSIONS : Based on the testing results, it was found that the change in buried depth and refiliing material would not significantly affect the pavement performance. However, it is noted that the final conclusion should be made based on an intensive structural analysis for the pavement under realistic conditions (i.e., repeated loading and environmental loading) along with the field test results.

• Journal of the Korean GEO-environmental Society
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• v.13 no.12
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• pp.59-66
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• 2012

In this study, it was sampling from heavy metal-contaminated soil with the waste in railroad workshop. And, the pollution concentration and analysis of particle-size distribution were conducted to design efficient purification process that it was aimed at high contaminated area, low contaminated area and samples containing waste foundry sand. But, it was the other signs of general soil contamination, as construction waste of waste concrete and waste wood, waste foundry sand, incinerator ash, etc is overall buried on the grounds. Thus, the common heavy metal purification technology has not decreased the pollution. However, heavy-metal contamination was reduced by magnetic separation utilizing the magnetic component of the mixed waste.