• Korean Journal of Construction Engineering and Management
• /
• v.15 no.5
• /
• pp.13-21
• /
• 2014

This study on condominium complex will adopt the quantitative assessment of the influence on the environment throughout the entire life cycle of buildings. This paper applies input-out analysis in order to analyse embodied energy regarding input of materials at material production phase. Also, it calculates environment load at use and demolition and destruction Phases of buildings as analysing energy consumption. The study categorises environment load as six impact categories and undertakes environmental impact evaluation. The consequence shows that the environment load of multi-unit dwelling takes up 88.2% out of the entire environment load of condominium complex. Also, as a result of analyzing the environmental impact of the life cycle of condominium buildings, it was found that such environmental impact comprised of about 11.96% of all industries in Korea that had an environmental impact.

• Earthquakes and Structures
• /
• v.12 no.3
• /
• pp.349-357
• /
• 2017

The design of reinforced concrete structures strongly depends on the value of the compression concrete strength used for the structural components. Given the uncertainties involved on the materials quality provided by concrete manufacturers, in the construction stage, these components may be either over or under-reinforced respect to the nominal condition. If the structure is under reinforced, and the deficit on safety level is not as large to require the structure demolition, someone should assume the consequences, and pay for the under standard condition by means of a penalty. If the structure is over reinforced, and other failure modes are not induced, the builder may receive a bonus, as a consequence of the higher, although unrequested, building resistance. The change on the building safety level is even more critical when the structure is under a seismic environment. In this research, a reliability-based criteria, including the consideration of expected losses, is proposed for bonification/penalization, when there are moderated differences between the supplied and specified reinforced concrete strength for the buildings. The formulation is applied to two hypothetical, with regular structural type, 3 and 10 levels reinforced concrete buildings, located on the soft soil zone of Mexico City. They were designed under the current Mexican code regulations, and their responses for typical spectral pseudoaccelerations, combined with their respective occurrence probabilities, are used to calculate the building failure probability. The results are aimed at providing objective basis to start a negotiation towards a satisfactory agreement between the involved parts. The main contribution resides on the explicit consideration of potential losses, including the building and contents losses and the business interruption due to the reconstruction period.

• Structural Engineering and Mechanics
• /
• v.47 no.5
• /
• pp.701-711
• /
• 2013

People started to replace natural aggregate with recycled aggregate for a number of years due to disposal problem and certain other potential benefits. Though there are number of drawbacks with use of recycled aggregates like lesser modulus of elasticity, low compressive strength, increase in shrinkage, there are results of earlier studies that use of chemical and mineral admixtures improves the strength and durability of recycled concrete. The use of recycled aggregate from construction and demolition wastes is showing prospective application in construction as alternative to natural aggregates. It conserves lot of natural resources and reduces the space required for the landfill disposal. In the present research work, the effect of recycled aggregate on strength and durability aspects of concrete is studied. Grade of concrete chosen for the present work is M50 (with a characteristic compressive strength of 50 MPa). The recycled aggregates were collected from demolished structure with 20 years of age. Natural Aggregate (NA) was replaced with Recycled Aggregate (RA) in different percentages such as 25, 50 and 100 to understand its effect. The experiments were conducted for different ages of concrete such as 7, 14, 28, 56 days to assess the compressive and tensile strength. Durability characteristics of recycled aggregate concrete were studied with Rapid chloride penetration test (as per ASTMC1202), sorptivity test and acid test to assess resistance against chloride ion penetration, capillary suction and chemical attack respectively. Mix design for 50 MPa gives around 35 MPa after replacing natural aggregate with recycled aggregate in concrete mix and the chloride penetration range also lies in moderate limit. Hence it is understood from the results that replacement of NA with RA is very much possible and will be ecofriendly.

• Advances in environmental research
• /
• v.1 no.1
• /
• pp.1-14
• /
• 2012

We demonstrated that reductive degradation of 2,4,6-Trinitrotoluene (TNT) and hexahydro-1,3,5-trinitro-1,3,5-triazine (Royal Demolition Explosive, RDX) can be enhanced by bio-reduced iron-bearing soil minerals (IBSMs) using Shewanella putrefaciens CN32 (CN32). The degradation kinetic rate constant of TNT by bio-reduced magnetite was the highest (0.0039 $h^{-1}$), followed by green rust (0.0022 $h^{-1}$), goethite (0.0017 $h^{-1}$), lepidocrocite (0.0016 $h^{-1}$), and hematite (0.0006 $h^{-1}$). The highest rate constant was obtained by bio-reduced lepidocrocite (0.1811 $h^{-1}$) during RDX degradation, followed by magnetite (0.1700 $h^{-1}$), green rust (0.0757 $h^{-1}$), hematite (0.0495 $h^{-1}$), and goethite (0.0394 $h^{-1}$). Significant increase of Fe(II) was observed during the reductive degradation of TNT and RDX by bio-reduced IBSMs. X-ray diffraction and electron microscope analyses were conducted for identification of degradation mechanism of TNT and RDX in this study. 4-amino-dinitrotoluene were detected as products during TNT degradation, while Hexahydro-1-nitroso-3,5-dinitro-1,3,5-triazine, Hexahydro-1,3-dinitroso-5-nitro-1,3,5triazine, and Hexahydro-1,3,5-trinitroso-1,3,5-triazine were observed during RDX degradation.

• Journal of The Korean Society of Agricultural Engineers
• /
• v.63 no.3
• /
• pp.97-105
• /
• 2021

Most of the rural development projects for the welfare of residents are mainly new construction and remodeling projects for community buildings such as village halls and senior citizens. However, in the case of the construction industry, it has been studied that 23% of the total carbon dioxide emissions generated in Korea are generated in the building-related sector. (GGIC, 2015) In order to reduce the emission of environmental pollutants resulting from construction of rural community buildings, there is a need to establish a system for rural buildings by predicting the environmental impact. As a result of this study, the emissions of air pollutants from buildings in rural communities were analyzed by dividing into seven stages: material production, construction, operation, maintenance, demolition, recycling, and transportation activities related to disposal. As a result, 12 kg of carbon dioxide (CO), 0.06 kg of carbon monoxide (CO), 0.02 kg of methane (CH), 0.04 kg of nitrogen oxides (NO), 0.02 kg of sulfurous acid gas (SO), and non-methane volatile organics per 1m of buildings in rural communities It was analyzed that 0.02 kg of compound (NMVOC) and 0.00011 kg of nitrous oxide (NO) were released. This study proved that environmentally friendly design is possible with a quantitative methodology for the comparison of operating energy and air pollutant emissions through the design specification change based on the statement of the rural community building. It is considered that it can function as basic data for further research by collecting major structural changes and materials of rural community buildings.

• Journal of the Korean Geosynthetics Society
• /
• v.20 no.4
• /
• pp.113-124
• /
• 2021

Underground environmental infrastructure and energy production facilities, which are recognized as avoidable facilities such as landfills, are emerging as an important social issue due to urbanization and economic growth. In order to safely construct a large-scale plant facility in the underground space, it is necessary to increase the utilization of the limited space layout and minimize unnecessary columns. In this study, the plant modularization method(Pipe Rack Module) was reviewed to solve the problems of work constraints, assembly and demolition, process system interconnection, and maintenance that occur when plant facilities are underground. In addition, plant module analysis was performed by applying various load conditions (earthquake load, device load, earth pressure load, etc.) to improve spatial layout usability and secure structure stability. Based on the analysis results under various boundary condition, the implications regarding the minimum installation interval and module arrangement (draft) of basic modules required for the construction of an underground combined plant were derived.

• Korean Journal of Construction Engineering and Management
• /
• v.11 no.5
• /
• pp.53-64
• /
• 2010

Remodeling becomes the significant issue in the aspect of the resource recycling, because it does not demolishes the whole buildings, but a part of main structure. However, compared with new construction, remodeling has several problems of adding the repair and rehabilitation works, using the partial demolition method, and having difficulties of making decision due to disagreement between several owner organizations. BIM, which is the total solution for managing and producing information during whole life cycle of the buildings, seems to be the right solution for the way to address these issues. has a possibility for solving the problems. Therefore this paper provided the framework and database for applying the BIM in the remodeling, and proved the applicability of the BIM database in the remodeling project through the case studies.

• Korean Journal of Construction Engineering and Management
• /
• v.6 no.6 s.28
• /
• pp.171-180
• /
• 2005

Public rental housing is constructed, owned, and managed by the public sector. The public institution for the public rental housing controls the whole building life cycle from the construction to the demolition. The construction company for the house built for sale is strongly interested in the cost for the initial investment, while the public institution is more focused on the maintenance cost for the preservation of the buildings Nevertheless, the maintenance cost of the public rental housing has been only managed as the accounting factor without the systemic research and analysis on the actual condition. This paper shows how expenses are related to the degree of obsolescence and presents the differences of the maintenance costs by the housing area and expenditure trends (vs time) of the maintenance costs, through analyzing time series data of public rental housing maintenance cost. Further, this paper helps understanding the causes of the differences of the maintenance costs by housing areas and characteristics of the expenditure trends. After all, this paper contributes to the improvement of the reliability and the practicality for the Life Cycle Cost modeling and the maintenance cost estimating.

• 한국문화재보존과학회:학술대회논문집
• /
• 2002.02a
• /
• pp.21-31
• /
• 2002

Lime-soil consolidations are very important as structural material, bonding material, waterproofing material, and finishing material in korea traditional buildings. In this study, we investigated site application trouble in korea traditional buildings being repaired or restored, and propose following solutions. 1) To diminish quality variation occurred by slaking quick-lime in site, it is desirable to use slaked-lime for lime-soil consolidation. 2) For uniform construction of lime-soil consolidation, we would recommend builders to use mixer to be uniform mixture, premixed type materials and compacting machine in field, 3) and to use rigid suitable temporary construction as scaffold for preventing traditional buildings from additional damage occurred in demolition and construction of a layer of lime-soil consolidation of a roofing. 4) For suitable repair of traditional buildings, it is necessary to specify definitely materials and construction methods suggested by the standard specifications for repair of the cultural property.

• Proceedings of the Korean Institute Of Construction Engineering and Management
• /
• autumn
• /
• pp.439-443
• /
• 2001

A lot of buildings, especially apartment housing, have been dismantled so as to enhance the value of the building without exact assesment for the service life and deterioration degree of the building. Remodeling for an aged building is becoming a hot issue to owners in the public sector and the private sector. Peoples including owner, tenants, constructors recognize the fact that the efficient maintenance of the building during the service life and lengthening the practical service life are very important in point of minimizing LCC. This study suggest a decision making system to judge whether to remodel(renovate) or to reconstruct an aged building. The system is composed of structural performance assesment elapsed(or practical service) life evaluation against whole service life, deterioration assesment of the building equipment, dweller's satisfaction, etc.