• International Journal of Highway Engineering
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• v.7 no.1 s.23
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• pp.21-29
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• 2005

One way to recycle the construction wastes is to use the waste concrete aggregates as the pavement materials. Although there are many studies and technical developments about waste concrete aggregates, the impurities produced in the process of the aggregate production prevent the use of the waste concrete aggregates in the pavement construction. In this study, the impurities included in the recycled waste aggregates were classified into inorganic and organic ones according to their characteristics, and the influences of each impurities on the pavement performance were presented. It was also showed that the limit of impurity content in the lean concrete base through the correlation between the inorganic impurity content and the compressive strength, and that in the granuler subbase layer through the correlation between the organic impurity content and the modified CBR. In conclusion, it is possible to apply waste concrete aggregates for the pavement when inorganic impurity content is less than 10% in the lean concrete base, and organic impurity content is less than 2% in granular subbase.

• Magazine of RCR
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• v.14 no.3
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• pp.17-25
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• 2019

• Korean Journal of Construction Engineering and Management
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• v.5 no.4 s.20
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• pp.115-121
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• 2004

The purpose of this study is to develop checklist and manual in order to control and manage military construction project in an environmentally friendly way during each stage in construction. The main contents of the study are as follows. 1) Checklists and manual are developed for reviewing the construction project in advance to meet environment codes and regulations during each stage of project. 2) Critical check points of environment management program focused on waste are identified. 3) A new construction paradigm in harmony with sound environment is established through the application of program for proactive waste control. The study also recommends that, as a future research, the development of a web-based manual be developed for more easy applications in general construction project.

• Journal of the Korean Recycled Construction Resources Institute
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• v.4 no.4
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• pp.371-378
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• 2016

In this study, a small portable sorting pilot for separation that can be used in dismantling construction site, which is the stage of construction waste generation, was developed, and its separation efficiency was evaluated to increase the actual recycling rate of the construction waste. The pilot was developed as portable sorting pilot for separation of 6 ton capacity that can handle one arm roll box within a $15m^2$ area in consideration of narrow places in the downtown area where a number of dismantling sites are located and various processes performed in the dismantling sites. In order to evaluate the efficiency performance of the developed device, the separation and sorting were carried out ten times with respect to trommel rotational speed RPM 2-3, 4-6 and 7-8. According to the results, the highest efficiency of about 90% was shown at RPM 6-7.

• Korean Journal of Construction Engineering and Management
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• v.11 no.2
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• pp.116-123
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• 2010

Since the Enforcement Decree of the Housing Act was changed in 2007, remodeling demands have increased. For this reason, many research studies are actively discussed for vitalizing remodeling, but countermeasure plan for generated construction waste is not enough. This study aims to provide basic data for the reduction plan of construction waste caused by the remodeling project through the investigation of apartments residents' priorities about remodeling elements for reducing construction waste. In this study, remodeling elements have been drawn through the literature investigation. As a result, subordinates were classified into 21 elements and superordinate were classified into 6 elements. Expert interviews were conducted to check the reliability about subordinate and superordinate elements of remodeling and the questionnaire survey were conducted to determine the residents preference of apartments remodeling elements. As a result of the questionnaire survey, we found out the characteristic of preference for apartments remodeling elements such as the period of apartment, the location and the financial condition respectively. This study presents a basic data for considering the remodeling as well as the apartment plans for the resident's preference. Further, many studies about the reduction plan of construction waste caused by the remodeling project will have to be discussed.

• Resources Recycling
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• v.24 no.5
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• pp.40-55
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• 2015

The purpose of this study is to analyse whether the waste disposal volume level in the construction waste disposal industry makes a different effect on earnings management behaviour by size of the licensed storage capacity and by location of the waste disposal site. The empirical results of this study are as follows. First, the waste disposal volume significantly influences earnings management behavior. When it comes to the size of licensed storage capacity in the small-sized capacity firms, the smaller waste disposal volume firms make more aggressive earnings management by using discretionary accruals. On the other hand, in the large-sized capacity firms, more waste disposal volume firms report higher earnings by adjusting more discretionary accruals. Second, the effects of waste disposal volume on the earnings management show different pattern depending on the location of waste disposal site. When the firms are located in the non-capital regions, the smaller waste disposal volume firms report higher earnings by adjusting discretionary accruals as well as by using real activities earnings management. However, the firms located in the capital regions show more aggressive earnings management when they have higher waste disposal volume level.

• Journal of the Korea Institute of Building Construction
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• v.5 no.3 s.17
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• pp.109-116
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• 2005

Recently, there have been many studies seeking towards the utilization of cementitious powder from concrete waste as recycled cement. However, most of the studies actually have been researches about the reuse of mortar or paste, not concrete waste. In fact, either mortar or paste is quite different from a real concrete waste in terms of age and mixture. Thus the purpose of this study is to examine basic physical properties of recycled cement, manufactured with cementitious powder from concrete waste, and analyze differences in chemical and hydraulic properties of the cement and its tested model. As a result of the chemical analysis, recycle cement is composed mainly of CaO and $SiO_2$, and that it is even lower in the content of CaO than Portland cement, which is also supported by previous studies. But, Differently from previous studies, calcining temperature of 650 was found an optimal condition under which cementitious powder from concrete waste could restore its hydraulic properties.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2004.05a
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• pp.57-60
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• 2004

Recently. as the alternatives to preserve environment such as effective usage of wastes or unusable resources are drawing attentions, researches and measures for the two tasks, which are reuse of waste wood and development of eco-friendly materials, are being examined and established in various fields. However, they are still insufficient. Therefore, in this study, for the efficient application of waste woods and eco-friendly effects, mortar was produced using sawdust af the waste wood and mineral material cement for combination, in order to produce inorganic boards using waste woods, which were made when sawing. The present study purposed to analyze the physical and dynamic characteristics of woody cement boards, which were made by modifying water-cement ratio for each wood inclusion rate based on a hardening-accelerator inclusion rate set in previous studies and, based on the findings. to provide basic data about the physical properties of inorganic boards made of waste wood, in order to Produce woody cement boards using waste wood, which has problems in being used in the manufacturing of woody cement boards.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2005.05a
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• pp.69-72
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• 2005

Recently, there have been many studies seeking towards the utilization of cementitious powder from concrete waste as recycle cement. However, most of the studies actually have been researches about the reuse of mortar or paste, not concrete waste. In fact, either mortar or paste is quite different from a real concrete waste in terms of age and mixture. Thus the purpose of this study is to examine basic physical properties of recycle cement, manufactured with cementitious powder from concrete waste, and analyze differences in chemical and hydraulic properties of the cement and its tested model. As a result of the chemicai analysis, recycle cement is composed mainly of CaO and SiO2, and that it is even lower in the content of CaO than Portland cement, which is also supported by previous studies. But, Differently from previous studies, plastic working at the temperature of 650 was found an optimal condition under which cementitious powder from concrete waste could restore its hydraulic properties.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2003.11a
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• pp.73-76
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• 2003

Recently, as the alternatives to preserve environment such as effective usage of wastes or unusable resources are drawing attentions, researches and measures for the two tasks, which are reuse of waste wood and development of eco-friendly materials, are being examined and established in various fields. However, they are still insufficient. Therefore, in this study, for the efficient application of waste woods and eco-friendly effects, mortar was produced using sawdust as the waste wood and mineral material cement for combination, in order to produce inorganic boards using waste woods, which were made when sawing. This study attempted to suggest a basic material about the physical properties of mortar, which used waste woods, after examining the features of wood mixture rate, water-cement rate, congelation according to the mixture rate of the setting accelerator, specific gravity, compression intensity, and bending intensity as experiment factors.