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In the past few decades, there have been numerous attempts to add plastic aggregates composed of polymeric materials to cementitious composites, either as an alternative to using natural aggregates or as fillers and fibers. However, the addition of plastic aggregates often results in cementitious composites with lower mechanical performance. In this paper, we attempt to address this issue by applying gamma irradiation technology to restore the mechanical performance. We aimed to determine the optimal gamma irradiation and mixing combinations by comparing the experimental results with information summarizing the recent literature related to the use of gamma-irradiated plastic aggregates within cementitious composites. To this end, the effects of changes in the physical and chemical properties of plastics due to irradiation with gamma irradiation on the strength of cementitious composites were evaluated using irradiation doses of 25, 50, 75, and 100 kGy and various plastic materials as key parameters. In the compressive strength test, it was found that adding gamma-irradiated plastic increased the compressive strength of the cementitious composites compared to the nonirradiated plastic. This suggests that the irradiation of plastic aggregates with gamma rays is an effective method to recover some of the strength lost when plastic aggregates are added to cementitious composites. In addition, modifications in the microstructure and chemical properties of the gamma-irradiated plastic were analyzed through SEM and FT-IR analysis, which allowed the determination of the strength enhancement mechanism. The results of this study show the possibility of the state-of-the-art performance improvement method for using plastic aggregate as a substitute for natural aggregate, going further from the plastic performance improvement technology for limited materials and radiation dose presented in previous studies.

As small obsolete buildings are exposed to high fire risks, governments are trying to evaluate their fire risks and preferentially improve fire protection performance for high risk buildings, however, the evaluation manpower and time are insufficient compared to the rapidly increasing number of obsolete buildings. Therefore, this study aimed to derive major fire risk index (FRI) evaluation items as part of developing a platform to quickly and efficiently evaluate fire risks in dense areas of small obsolete buildings utilizing spatial information convergence technology. To this end, 20 preliminary evaluation items specifically tailored to dense areas of small obsolete buildings were derived through a field survey, investigation of FRI evaluation items from existing works, and expert pre-reviews. Based on the derived 20 preliminary items, an importance survey was conducted with a total of 181 fire safety experts including fire officers, university professors, researchers, industry experts, and fire insurers. As a result, a total of 12 major evaluation items (e.g., outdoor fire extinguisher, distance to 119 Safety Center, building structure, building cladding, illegal alterations, illegal parking, and liquefied natural gas cylinder) were derived. Results can help to evaluate the fast and efficient fire risks in dense areas of small obsolete buildings.

The purpose of this study was to identify the major wastes generated during the construction phase using a life cycle assessment. To accomplish this, the amount of waste generated in the construction phase was deduced using the loss rate and weight conversions. Major construction wastes were assessed using six comprehensive environmental impact categories, including global warming potential, abiotic depletion potential, acidification potential, eutrophication potential, ozone depletion potential, and photochemical ozone creation potential. According to the analysis results, five main construction wastes&mdash, concrete, rebar, cement, polystyrene panel, and concrete block&mdash, comprehensively satisfied the 95% cutoff criteria for all six environmental impact categories. The results of the environmental impact characterization assessment revealed that concrete, concrete block, and cement waste accounted for over 70% of the contribution level in all the environmental impact categories except resource depletion. Insulation materials accounted for 1% of the total waste generated but were identified by the environmental impact assessment to have the highest contribution level.

In the construction industry, concerted efforts are being made to quantitatively evaluate the environmental impacts of building materials and buildings using the life cycle assessment (LCA) approach. However, the existing building LCA model applies different evaluation systems and standards to building materials and buildings; thus, interlinking and integrating their evaluated values are made difficult. To overcome this problem, this study aims to develop an integrated building LCA model that enables the integration of all LCA results related to building materials used for constructing a building, the building components, and the whole building. First, the building LCA methods and certification criteria employed by major green building certification systems [Leadership in Energy & Environmental Design (LEED), Comprehensive Assessment System for Built Environment Efficiency (CASBEE), Building Research Establishment Environmental Assessment Methodology (BREEAM), and Green Standard for Energy and Environmental Design (G-SEED)] were analyzed. Then, an integrated building LCA model that allows integration of the LCA results for building materials into those of the LCA of building components and the whole building was developed. Finally, we established an application plan for a stepwise application of the integrated building LCA model to G-SEED, a Korean green building certification system. The feasibility of the integrated building LCA model was confirmed by comparing it with the existing building LCA model in a case analysis, which demonstrated the applicability of the proposed integrated building LCA method in terms of building materials, building components, and whole building.

A number of studies have evaluated life-cycle CO2 emissions and related emission-reduction technologies that can contribute towards a low carbon construction industry; specific attention has also been paid to apartment buildings. There has also been much focus on long-life building technologies as a major means to reduce carbon emissions from the construction industry. These developments are accompanied by a need to develop models for quantitative evaluation of building service life and of life-cycle CO2 emissions. This study thus aims to evaluate service life and life-cycle CO2 emission reductions, and to develop a low carbon durability design for apartment buildings, utilizing green technologies to satisfy these twin goals. To this end, three types of green technology groups that could be applied to apartment buildings were selected. Furthermore, a method to estimate the service life of apartment buildings was applied to evaluation measures of CO2 emissions, in order to identify evaluation measures for CO2 emission reduction performance and service life. The life cycle of apartment buildings was divided into four phases: construction, operation, maintenance, and disposal phases, with CO2 emission evaluation measures considered for each phase. A case study was also analyzed in order to validate the reliability of the proposed low carbon durability design. The study result showed that it is possible to analyze the characteristics of life-cycle CO2 emission reductions and the service life of apartment buildings using green technologies; 36 technologies capable of satisfying the 40% life-cycle CO2 emission reductions target and the 100-year service life target were selected.

To evaluate the embodied environmental impact of buildings, major building tasks and materials which contribute to these impacts should be analyzed in advance according to the characteristics of buildings and regional environment. Such evaluation, for which techniques are currently being developed, may be used to reduce these impacts. This study aimed to analyze major building tasks and materials in order to evaluate the embodied environmental impacts of apartment buildings in Korea. Six apartment buildings (three types of structure: wall, rigid-frame, and flat-plate) recently constructed in Seoul, Korea were quantitatively evaluated based on a life cycle assessment method in terms of embodied environmental impacts (i.e., global warming, acidification, eutrophication, ozone layer depletion, photochemical oxidation, and abiotic depletion potentials). The results were analyzed based on building tasks and materials according to the structure type of the apartment building. As a result, five major building tasks (reinforced concrete work, masonry work, glass work, plaster work, and carpentry work) and six major building materials (ready-mixed concrete, rebar, insulating materials, concrete bricks, glass, and gypsum boards) were identified, accounting for more than 95% of the values of six environmental impact categories.

Since the early 2000s, systems for evaluating the life cycle CO2 (LCCO2) emissions of buildings have been developed in order to reduce emissions and help prevent global warming caused by greenhouse gases. However, existing systems have limitations in that they only support a one-time evaluation of CO2 emissions during the early planning or progress phase and cannot effectively provide feedback on evaluation results. Hence, this study aimed to develop an integrated assessment system that periodically evaluates and manages LCCO2 emissions of a single building according to project processes, consisting of the early planning, progress, and construction phases. To this end, requisite factors for the integrated assessment system were analyzed, and the concept of this system was designed, including models for simple assessment, detailed assessment, construction site assessment, and result analysis. Further, the life cycle stages of buildings were classified into the production, construction, operation, and end-of-life stages, and a CO2 emissions evaluation method and database were established to implement the evaluation model. Through this process, the web-based integrated assessment system was developed, and its practical applicability was verified through a case study.

This study assessed the influence of matter discharged during the production (dry/wet) of recycled aggregate on global warming potential (GWP) and acidification potential (AP), eutrophication potential (EP), ozone depletion potential (ODP), biotic resource depletion potential (ADP), photochemical ozone creation potential (POCP) using the ISO 14044 (LCA) standard. The LCIA of dry recycled aggregate was 2.94 &times, 10&minus, 2 kg-CO2eq/kg, 2.93 &times, 5 kg-SO2eq/kg, 5.44 &times, 6 kg-PO43eq/kg, 4.70 &times, 10 kg-CFC11eq/kg, 1.25 &times, 5 kg-C2H4eq/kg, and 1.60 &times, 5 kg-Antimonyeq/kg, respectively. The environmental impact of recycled aggregate (wet) was up to 16~40% higher compared with recycled aggregate (dry), the amount of energy used by impact crushers while producing wet recycled aggregate was the main cause for this result. The environmental impact of using recycled aggregate was found to be up to twice as high as that of using natural aggregate, largely due to the greater simplicity of production of natural aggregate requiring less energy. However, ADP was approximately 20 times higher in the use of natural aggregate because doing so depletes natural resources, whereas recycled aggregate is recycled from existing construction waste. Among the life cycle impacts assessment of recycled aggregate, GWP was lower than for artificial light-weight aggregate but greater than for slag aggregate.

The objective of this paper is to analyze the control conditions of the transmittance rate, and determine the conditions that are most optimal with respect to building energy and daylight performance in three climate conditions: Riyadh, Saudi Arabia (hot climate), Inchon, South Korea (hot and cold climate), and Moscow, Russia (cold climate). The analysis was based on the electrochromic glass developed by a research team. Electrochromic glass is a next generation solar control glass that can control the transmittance of the glass itself. Therefore, proper control methods are essential for rational use of this electrochromic glass. To properly control electrochromic glass, daylight performance must be considered, along with building energy (heating, cooling, and lighting). If only building energy is considered, transmittance needs to be lowered during the summer season and increased during the winter season. Controlling electrochromic glass transmittance with such a method would not improve the satisfaction of users and occupants of a building due to the resulting glare. In addition to energy reduction, the basic function of solar control glass is to prevent glare. Therefore, in this study, we develop the Energy and Daylight Performance Index (EDPI) using, to evaluate the combined building energy and daylight performance and deduce the optimal control method for electrochromic glass. In addition, optimal control conditions for the three different climatic regions were obtained. Limitations of this study were that the scope was restricted to the eastern climate region, and that the building analysis model was limited to one climate region. It is expected that the optimal control method could be used as an initial database in the development of a electrochromic glass control system.

Numerous factors affect the soil pressure distributions around buried pipes, including the shape, size, and stiffness of the pipe, burial depth, and the stiffness of the surrounding soil. Additionally, to some extent, a pipe can benefit from the soil arching effect, where the overburden and surcharge pressure at the crown can be supported by the adjacent soil. As a result, a buried pipe only needs to support the portion of the load that is not transferred to the adjacent soil. This paper presents numerical investigations of the soil pressure distributions around buried concrete pipes and crack propagation under different environmental conditions, such as loading, saturation level, and the presence of voids. To this end, a nonlinear elastoplastic model for backfill materials was implemented using finite element software and a user-defined subroutine. Three different backfill materials and two different native soils were selected to examine the material-specific behaviors of concrete pipes, including soil pressure distributions and crack propagation. For each backfill material, the effects of the loading type, groundwater, and voids were investigated. These simulation results provide helpful information regarding pressure redistribution and buried concrete pipe behavior under various environmental conditions.

This study analyzed the characteristics of the environmental impacts of apartment buildings, a typical housing type in South Korea, as part of a research project supporting the streamlined life cycle assessment (S-LCA) of buildings within the G-SEED (Green Standard for Energy and Environmental Design) framework. Three recently built apartment building complexes were chosen as study objects for the quantitative evaluation of the buildings in terms of their embodied environmental impacts (global warming potential, acidification potential, eutrophication potential, ozone layer depletion potential, photochemical oxidant creation potential, and abiotic depletion potential), using the LCA approach. Additionally, we analyzed the emission trends according to the cut-off criteria of the six environmental impact categories by performing an S-LCA with cut-off criteria 90–99% of the cumulative weight percentile. Consequently, we were able to present the cut-off criterion best suited for S-LCA and analyze the effect of the cut-off criteria on the environmental impact analysis results. A comprehensive environmental impact analysis of the characteristics of the six environmental impact categories revealed that the error rate was below 5% when the cut-off criterion of 97.5% of the cumulative weight percentile was applied, thus verifying its validity as the optimal cut-off criterion for S-LCA.

Carbon emission reduction policies demand tighter building Life Cycle Assessment (LCA) qualification standards. However, it is widely believed that it will be difficult to efficiently reduce the carbon emissions of buildings with only a fragmentary revision of the qualification standards. For this reason, the Korean government has developed the Green Building Index Certification System (GBI certification system), which is a certification framework based primarily upon the carbon emissions of a building. There is currently no assessment program tailored to the GBI certification system. The purpose of this study is to develop the Building Life Cycle Carbon Emissions Assessment Program (BEGAS 2.0) to support Korea׳s GBI certification system. With a theoretical consideration of the GBI certification system, the building LCA qualification standards of other international green building certification systems were analyzed. These analyses enabled development of BEGAS 2.0 that reflects the characteristics of the GBI certification system and the current state of Korea׳s construction industry. Consequently, an appropriate building life cycle carbon emissions assessment program was developed, which can support Korea׳s GBI certification system effectively.

This study aims to compare the potential environmental impact of the manufacture and production of recycled and by-product aggregates based on a life cycle assessment and to evaluate the environmental impact and cost when they are used as aggregates in concrete. To this end, the six potential environmental impacts (i.e., abiotic depletion potential, global warming potential, ozone-layer depletion potential, acidification potential, photochemical ozone creation potential, and eutrophication potential) of the manufacture and production of natural sand, natural gravel, recycled aggregate, slag aggregate, bottom ash aggregate, and waste glass aggregate were compared using information from life cycle inventory databases. Additionally, the environmental impacts and cost were evaluated when these aggregates were used to replace 30% of the fine and coarse aggregates in concrete with a design strength of 24 MPa. The environmental impact of concrete that incorporated slag aggregate as the fine aggregates or bottom ash aggregate as the coarse aggregates were lower than that of concrete that incorporated natural aggregate. However, concrete that incorporated bottom ash aggregate as the fine aggregates demonstrated relatively high environmental impacts. Based on these environmental impacts, the environmental cost was found to range from 5.88 to 8.79 USD/m3.

As sustainable development has emerged as a priority on the international agenda, increasing emphasis has been placed on &ldquo, Life Cycle Sustainability Assessment (LCSA),&rdquo, wherein environmental, economic, and social performance are comprehensively integrated. This study, as part of an LCSA approach, uses Social Life Cycle Assessment (S-LCA) to analyze the worker category social impact for concrete plants in South Korea. For the analysis, three types of concrete plant with different operating systems were selected and evaluated: Direct operation, operated by dedicated concrete manufacturers, and operated by cement suppliers. Eleven major social topics, which were mentioned in the international standards and international institutes, were selected as the subjects of evaluation, the social impacts were evaluated by applying the evaluative criteria for social topics presented in the Handbook for Product Social Life Cycle Assessment of PR&eacute, Sustainability. We determined that the highest social impact was found in concrete plants operated by cement suppliers (0.77), followed by plants operated by dedicated concrete manufacturers (0.50), and finally by plants with direct operations (0.09). These results can be applied by concrete plants to improve worker category areas in which they are lacking and by future researchers to evaluate the sustainable development of a variety of industries.

Electrochromic glass is anticipated as the next generation of solar control glass for construction because it can control the transmittance of the glass itself. This study analyzed building energy and light environment performance by applying electrochromic glass in triple glazing in order to verify both the solar control characteristics of electrochromic glass and its high insulation performance. This paper evaluates the performance of the electrochromic glass developed by our research team in Korea in five control conditions of varying temperatures and solar radiation levels. By analyzing the cooling and heating load, lighting energy, Daylight Glare Index (DGI), and interior illuminance when applying the selected conditions to office buildings, this paper discerns the optimal control conditions for electrochromic glass. To do so, the optical characteristic data of the electrochromic glass was analyzed via an experiment, and the creation of triple glazing for construction was conducted. The performance of electrochromic glass was evaluated by analyzing hourly and yearly data for cooling, heating load, and lighting energy during a typical day in summer and winter. From this analysis, the control condition with an outstanding performance from an energy perspective was identified. The performance of the light environment was assessed, and the EDPI overall evaluation index was used to find the electrochromic glass’ optimum control conditions for integrating energy and light environment.

In recent years, much research has been conducted internationally to quantitatively evaluate the environmental impact of buildings in order to reduce greenhouse gas emissions and address associated environmental problems. With this in mind, the Green Standard for Energy and Environmental Design (G-SEED) in South Korea was revised in 2016. However, the various possible evaluation methods make it difficult to conduct building life cycle assessment. Moreover, compared to research on residential buildings, life cycle assessment research on non-residential buildings is scarce. Therefore, this study analyzes primary building materials for life cycle assessment of current non-residential buildings to support Korean G-SEED requirements. Design documents for various non-residential buildings are obtained, and the types and numbers of materials used in production are determined. Next, the primary building materials contributing high cumulative weight based on the ISO14040 series of standards are analyzed. We then review the most commonly-used building materials while considering non-residential building types and structures. In addition, construction material reliability is evaluated using the environmental impact unit value. With our results, by suggesting the primary building materials in non-residential buildings, efficient life cycle assessment of non-residential buildings is possible in terms of time and cost.

In the building construction industry, simultaneous and integrated evaluation of a building’s environmental and economic performance in the early planning stage greatly facilitates stakeholders’ decision-making for sustainable building construction. This study aimed to develop a streamlined Environmental Life Cycle Costing (ELCC) model for buildings, applicable to the early planning stage of construction projects. To this end, we selected three of the private cost-related life cycle cost categories that are determinants of stakeholders’ decision-making in the early planning stage of construction and extracted 10 major building materials that account for over 95% of the total direct construction cost. Then, we developed a streamlined ELCC model for buildings by combining the monetary value-based life cycle analysis model, KOLID (Korean Life Cycle Impact Assessment Method Based on Damage-Oriented Modeling), and the present worth method. Finally, we conducted a case study to empirically verify the applicability of the proposed model.

Because the reduction in environmental impacts (EIs) of buildings using life-cycle assessment (LCA) has been emphasized as a practical strategy for the sustainable development of the construction industry, studies are required to analyze not only the operational environmental impacts (OEIs) of buildings, but also the embodied environmental impacts (EEIs) of building materials. This study aims to analyze the EEIs of Korean apartment buildings on the basis of major building materials as part of research with the goal of reducing the EIs of buildings. For this purpose, six types of building materials (ready-mixed concrete, reinforcement steel, concrete bricks, glass, insulation, and gypsum) for apartment buildings were selected as major building materials, and their inputs per unit area according to the structure types and plans of apartment buildings were derived by analyzing the design and bills of materials of 443 apartment buildings constructed in South Korea. In addition, a life-cycle scenario including the production, construction, maintenance, and end-of-life stage was constructed for each major building material. The EEIs of the apartment buildings were quantitatively assessed by applying the life-cycle inventory database (LCI DB) and the Korean life-cycle impact assessment (LCIA) method based on damage-oriented modeling (KOLID), and the results were analyzed.

Long-life apartment houses are sustainable buildings that use fewer resources and can reduce CO2 emission over the course of their life cycle. However, there have been few quantitative evaluations of the CO2 emission reduction effect when the life of apartment houses is increased. In this study, the CO2 emission reduction rate over the life cycle of long-life apartment houses (Types II and III) was evaluated using high durability and maintenance technologies from general apartment houses (Type I) as reference data. CO2 emissions over the life of the apartment houses were evaluated by dividing the life cycle into construction, operation, maintenance/management, and dismantlement/disposal phase. To achieve this goal, the life of apartment houses was calculated using the life calculation technique, and the CO2 emission amount over a 100-year evaluation period was compared. The life of general apartment houses was set to about 40 years, while that of long-life apartment houses, due to the application of long-life construction technologies, was set to more than 100 years. CO2 emissions of long-life apartment houses over their life cycle tended to decrease compared with that of general apartment houses. In particular, the maximum CO2 emission reduction rates of long-life apartment houses were 36.18% and 33.04%, respectively. © 2014 American Institute of Chemical Engineers Environ Prog, 34: 555–566, 2015

The purpose of this study is to propose a method of environment assessment in the field of building materials within Korea Green Building Certification (G-SEED). The method of environment assessment in the field of building materials was examined using LEED of the United States and BREEAM of the United Kingdom, the representative environment-friendly building certification systems in other countries. Especially, each revision of BREEAM was investigated for assessment methods such as environment assessment guidelines and assessment programs. In addition, assessment process and items were analyzed in relation to BREEAM. As a result, for environment assessment in the field of building materials within G-SEED, the method of connecting essential elements such as building material assessment guidelines and database networks with G-SEED was proposed.

The purpose of this study was to deduce the major construction wastes to be managed using environmental impact assessment for construction wastes generated in the construction phase. To accomplish this, the amount of construction waste discharged in the construction phase was analyzed using loss rate and weight conversion factor in the Standard of Estimate for Construction Works. Based on the result of construction waste generation deduced, major construction wastes were extracted with consideration on 6 comprehensive environmental impacts including potential, abiotic depletion potential, acidification potential, eutrophication potential, ozone depletion potential, and photochemical ozone creation potential. As a result, 5 major building materials such as concrete, concrete block, rebar, cement and polystyrene panel were deduced as major cpmstruction wastes in construction phase.

The purpose of this study is to assess greenhouse gas (GHG) emission reduction performance among certification criteria constituting “materials and resources” category, as a part of study that configures weighted values of categories for the Korea Green Building Scheme (G-SEED). For this purpose, the subjects of assessment were classified into “reference apartment house” newly constructed without application of certification criteria and “assessed apartment house” newly constructed with reflection of certification criteria. In addition, direct and indirect GHG emission reduction performance of the assessed apartment house was assessed from life cycle perspective in comparison to the reference apartment house, reflecting the purpose of assessment according to certification criteria within the “materials and resources” category. As a result, GHG emission reduction performance of “displaying carbon emission of material” and “recycling” were deduced to be extremely excellent. GHG emission reduction performance of “flexibility” and “reducing food waste” ware analyzed to be relatively satisfactory. On one hand, GHG emission reduction performance of “appropriateness of measure to reduce furniture materials” and “use of eco-friendly products” ware assessed to be relatively insufficient.

This study aims to develop a Building materials Embodied GHG Assessment Criteria and System (BEGAS) in the newly revised Korea Green Building Certification System (G-SEED). For this purpose, green building certification systems and supporting assessment systems were analyzed in order to grasp the current trend of the GHG emission assessment on building materials. The evaluands were selected by identifying the major building materials in the GHG emission assessment that meet the cut-off level of ISO 14040 for GHG emission assessment. In addition, standard quantity of GHG emissions were calculated for the G-SEED and BEGAS. An auto quantity input technique was presented using pure resource code, composed of standard work codes of the Public Procurement Service (PPS), as a medium, in order to support the easy assessment of GHG emission. Korea LCI DB, the Korean DB of environmental information on building materials, and the Korea carbon footprint labeling certificate were adopted to the database for analyzing the social features of Korea. As a result, based on the aforementioned database, the criteria of GHG emission assessment for building materials in Korea׳s G-SEED were proposed, and a web-based BEGAS was developed.

The purpose of this study is to assess environmental friendliness of passive apartment house based on major building materials in Korea. To accomplish this, stage-wise quantity information of life cycle and energy consumption data were established on major materials through theoretical consideration on life cycle assessment. In addition, basic unit database from Korean LCI DB was utilized to assess and analyze characterization value of global warming assessment. As a result, the value of global warming was smaller in passive apartment house in comparison to general apartment house. As the effect of building materials in construction stage was analyzed to be greater than the effect of energy consumption in operation stage, development of diverse building materials taking environmental impact into account is deemed necessary.

The purpose of this study is to propose a simplified environmental impact assessment method based on selection of major building materials for school buildings in Korea. To accomplish this, environmental impact of 2 school buildings constructed in Korea was assessed according to the procedure of life cycle assessment. In addition, major building materials of school buildings were selected from the perspective of 6 environmental impact categories based on the assessment result, and a method of simplified environmental impact assessment was suggested. On one hand, case analysis verified applicability of the simplified environmental impact assessment method proposed in this study by showing similar value within 10% compared to the assessment result from existing detailed assessment.

The aim of this study was to develop and evaluate the applicability of an optimum design program (SUSB-OPTIMUM) for the life cycle CO2 assessment of an apartment house that can be readily utilized during the planning and design phases. For this purpose, a database containing information on the CO2-reducing performance and the cost of environmentally-friendly construction technologies that are applicable to apartment houses was constructed, and an interpretation program was built based on a simplified technique for assessing the life cycle CO2 emissions of an apartment house and the unit costs based on the inter-industry relation table. In addition, by integrating the interpretation program with an optimum design system based on an evolutionary algorithm, an optimum design system was created to compute the optimal solution with regard to the life cycle CO2 emissions and economic feasibility of apartment buildings. The applicability of the optimum design program developed in this study was evaluated by means of a case study. The case study results revealed that it is possible to compute the optimum combination of environmentally-friendly construction technologies, as well as the quantity of life cycle CO2 emissions and costs in order to reach a CO2 emissions target at a cost comparable to that of a standard apartment house.

This study employs probabilistic analysis to evaluate the life cycle embodied environmental cost of Korean apartment buildings, with a focus on six major construction materials. To this end, the bill of materials was analyzed for 443 Korean apartment buildings according to the type and plan form, and probability density functions (PDFs) were established for the input quantities of the six materials under consideration. Life cycle scenarios were then examined for each material, and their respective life cycle embodied environmental cost factors were established, using a monetary valuation-based damage cost life cycle analysis model. The estimated environmental costs were evaluated by apartment structural type and plan form, based on probability distributions using the Monte Carlo simulation (MCS). Building life cycle embodied environmental cost was estimated between 16.87 USD/m2 and 23.03 USD/m2 (90% confidence interval). Among the structure types analyzed, the highest costs were associated with the wall structure, followed by rigid frame and flat plate structures, at the plan form level, costs followed the sequence plate-type &gt, mixed-type &gt, tower type for a given type of structure.

The production of concrete, a major construction material, emits a large amount of CO2 from the material production stage, such as in the production of cement, aggregates, and admixtures, to the manufacturing stage, and it is expected that a reduction of CO2 emission will be required. Accordingly, a study on the assessment of the appropriate amount of CO2 emission in the concrete production is necessary. As a result, in environmentally developed countries, studies have been conducted on the production of low-CO2-emitting concrete, such as a low-carbon concrete procurement system, but studies on this topic have been insufficient in Korea. Therefore, this study evaluated the appropriateness and the reduction performance of the low-carbon-emission concrete (LCEC) mix design system and the deduced mix design results using an evolutionary algorithm (EA), the optimal mix design method, which minimizes the CO2 emission of the concrete mix design. This study established a mix design database from approximately 800 concrete mix designs with different strengths and used an EA to deduce the optimal mix design. When deducing the optimal mix design, we considered design variables, object functions, and constraint functions to develop the algorithm. Then, the appropriateness and reliability of the mix design deduced from the optimal LCEC mix design system, which in turn was developed by using the above algorithm, were evaluated. Additionally, case studies of current structures in Korea were divided into the actual concrete mix designs and the deduced optimal mix designs, which were compared to analyze the CO2 emissions. According to the case study of the concrete mix design deduced from this assessment system, the CO2 emissions of the optimal mix design compared to the actual mix design were reduced by 4 and 7% for 24 and 30 MPa concrete, respectively.

Various tools that assess life cycle CO2 (LCCO2) emissions are currently being developed throughout the international community. However, most building LCCO2 emissions assessment tools use a bill of quantities (BOQ), which is calculated after starting a building's construction. Thus, it is difficult to assess building LCCO2 emissions during the early design phase, even though this capability would be highly effective in reducing LCCO2 emissions. Therefore, the purpose of this study is to develop a Building Simplified LCCO2 emissions Assessment Tool (B-SCAT) for application in the early design phase of low-carbon buildings in South Korea, in order to facilitate efficient decision-making. To that end, in the construction stage, the BOQ and building drawings were analyzed, and a database of quantities and equations describing the finished area were conducted for each building element. In the operation stage, the "Korea Energy Census Report" and the "Korea Building Energy Efficiency Rating Certification System" were analyzed, and three kinds of models to evaluate CO2 emissions were proposed. These analyses enabled the development of the B-SCAT. A case study compared the assessment results performed using the B-SCAT against a conventional assessment model based on the actual BOQ of the evaluated building. These values closely approximated the conventional assessment results with error rates of less than 3%.

The increased popularity of building information modeling (BIM) for application in the construction of eco-friendly green buildings has given rise to techniques for evaluating green buildings constructed using BIM features. Existing BIM-based green building evaluation techniques mostly rely on externally provided evaluation tools, which pose problems associated with interoperability, including a lack of data compatibility and the amount of time required for format conversion. To overcome these problems, this study sets out to develop a template (the “green template”) for evaluating the embodied environmental impact of using a BIM design tool as part of BIM-based building life-cycle assessment (LCA) technology development. Firstly, the BIM level of detail (LOD) was determined to evaluate the embodied environmental impact, and constructed a database of the impact factors of the embodied environmental impact of the major building materials, thereby adopting an LCA-based approach. The libraries of major building elements were developed by using the established databases and compiled evaluation table of the embodied environmental impact of the building materials. Finally, the green template was developed as an embodied environmental impact evaluation tool and a case study was performed to test its applicability. The results of the green template-based embodied environmental impact evaluation of a test building were validated against those of its actual quantity takeoff (2D takeoff), and its reliability was confirmed by an effective error rate of ≤5%. This study aims to develop a system for assessing the impact of the substances discharged from concrete production process on six environmental impact categories, i.e., global warming (GWP), acidification (AP), eutrophication (EP), abiotic depletion (ADP), ozone depletion (ODP), and photochemical oxidant creation (POCP), using the life a cycle assessment (LCA) method. To achieve this, we proposed an LCA method specifically applicable to concrete and tailored to the Korean concrete industry by adapting the ISO standards to suit the Korean situations.

This study classified the life cycle of buildings into a construction stage, an operation stage, a maintenance stage and a dissolution/disposal stage, and proposed a CO2 assessment method for each stage for the purpose of creating a simple life cycle CO2 assessment system for apartment houses. Specifically in the construction stage, major construction materials that are the source of more than 80% of CO2 emissions produced during building construction were selected, and a method of evaluating CO2 emissions for five standard apartment houses was proposed. In addition, amounts of CO2 emissions generated during the building operation stage and the maintenance stage were calculated based on the “Green Home Certification System” and the “Apartment House Building Long Term Repair Plan and Repair Rate” of the Korean Ministry of Land, Transportation and Maritime Affairs. For the dissolution/disposal stage, a CO2 assessment method was proposed that would enter into a database the amount of oil used by disposal equipment and other related types of machines, and analyze the process of waste treatment. Also, the potential of applying a simple assessment program was evaluated in connection with a life cycle CO2 assessment simulation utilizing an actual apartment building. Consequently, the results of a building life cycle CO2 assessment using standard apartment houses as proposed in this study indicated a figure of 14,013.66 ton-CO2. That figure is similar to 11,640.00 ton-CO2 for existing apartment houses. In particular, the results of material production in the construction stage and CO2 calculation in the maintenance stage indicated significant results closely approximating the 80% of CO2 emissions attributed to construction material production noted earlier in this study at first.

The purpose of this study is to develop a simple method to assess the amount of carbon dioxide (CO2) emitted during the production of construction materials used in the construction of a standard Korean apartment house. This study is part of a wider effort to develop a system for evaluating the environmental load of construction during architectural planning and basic design phases. We formulated models of a standard Korean apartment house and a super high-rise apartment house, based on five reference floor plans for “green homes” provided by the Korean government. We identified major construction materials that account for over 80% of the CO2 emission that occurs during construction and built a database to evaluate the environmental loads of these materials according to house types described in terms of area, block type, combination of living units, or number of floors. We used the information in this database to develop technology to assess the amounts of CO2 that are emitted during the production of construction materials used to build residential apartment houses in Korea.

The complicated nature of interior construction works makes the detailed progress monitoring challenging. Current interior construction progress monitoring methods involve submission of periodic reports and are constrained by their reliance on manually intensive processes and limited support for recording visual information. Recent advances in image-based visualization techniques enable reporting construction progress using interactive and visual approaches. However, analyzing significant amounts of as-built construction photographs requires sophisticated techniques. To overcome limitations of existing approaches, this research focuses on visualization and computer vision techniques to monitor detailed interior construction progress using an object-based approach. As-planned 3D models from Building Information Modeling (BIM) and as-built photographs are visualized and compared in a walk-through model. Within such an environment, the as-built interior construction objects are decomposed to automatically generate the status of construction progress. This object-based approach introduces an advanced model that enables the user to have a realistic understanding of the interior construction progress.

The building industry is currently strengthening the building life cycle assessment (LCA) criteria of the green building certification system to encourage carbon emission reduction. However, the voluntary approach of the LCA criteria does not provide sufficient incentive to effectively drive green building construction. Furthermore, additional costs associated with green building construction are not given enough weightage, thus hampering the incorporation of green building technologies. This study developed a Green Building Index (GBI) Certification System to effectively reduce carbon emissions in South Korea&rsquo, s building industry. Consequently, the assessment areas for green buildings were divided into a carbon emission index, a building habitability index, and a carbon economic index, and assessment methods were suggested for each area. In addition, eco-efficiency, which represents an environmental value, was incorporated into the three indices from the perspective of green building certification and used to estimate a GBI that represents overall building sustainability. This GBI was then integrated into an overall GBI Certification System, and a case study was used to evaluate its applicability. The results indicate the validity of the proposed GBI Certification System, which promotes voluntary carbon emission reduction by evaluating cost effectiveness based on life cycle carbon emissions and carbon economic efficiency.

Well-depicted baseline, systematic data collection, rigorous comparison of the as-planned and as-built progress and effective presentation of measured deviations are key ingredients for effective project control. Existing construction progress monitoring techniques are constrained by their reliance on ad-hoc approaches. This chapter presents advanced computer visualization and color and pattern coding techniques to compare the as-planned with the as-built construction progress. Key objective is to provide a method for automated collection, analysis and visual reporting of construction progress to facilitate the decision-making process. Construction progress is visualized by superimposing 3D Building Information Models (BIM) over construction photographs. The framework uses context-aware technologies to capture user’s context and the need for information. A complementary 3D walkthrough environment provides users with an intuitive understanding of the construction progress using color coding and patterns.