Buildings In South Korea Research Articles

Identifying stack-driven indoor environmental problems and associated pressure difference in high-rise residential buildings: Airflow noise and draft

Building airflow is a main factor in indoor air and environmental qualities. In particular, stack-induced airflow can cause indoor environmental problems in high-rise buildings over the winter due to the strong driving force (pressure difference). The goal of this study was to identify the actual characteristics of stack-driven environmental problems in real high-rise residential buildings through a field survey and airflow simulation. We collected the actual resident complaints (140 cases) raised in six high-rise residential buildings in South Korea during three years. The most frequent complaints were airflow noise and drafts at residential entrance doors. Then, by a calibrated airflow simulation, we identified the unknown pressure differences that caused these two problems. Based on the pressure differences, this study could determine problem occurrence rates for noise and drafts depending on given pressure differences. Apart from the existing allowable or reference pressure difference (50 Pa) across doors suggested by ASHRAE and European standards (EN 12101-6), which is related to emergency escape, three reference levels were suggested: (1) tight: 25 Pa, (2) normal: 40 Pa, and (3) loose: 65 Pa. These values were intended to be used as the reference in predicting or solving the stack-driven problems. Finally, we successfully predicted the frequency of these problem occurrences over the winter in a target building, using a coupled airflow and thermal simulation. These results showed the importance of the newly suggested references, 25 Pa or 40 Pa rather than 50 Pa, in identifying the stack-driven airflow noise and draft.

From Uniformity to Sustainable Diversity: Exploring the Design Attributes of Renovating Standardized Classrooms in Korea

Modern school buildings in South Korea, which were until the 1990s typically designed with standardized and monotonous features based on drawings provided by the government, are shifting to more well-designed spaces under a student-centered approach in this more creative and imaginative era. The purpose of this study is to examine the renovation priorities of design features based on the preferences of architects and educators, paying particular attention to classroom design for enhancing students’ spatial and aesthetic experiences. For this unusual approach, architects and school educator groups, who jointly plan the renovation of traditional classrooms, were surveyed on classroom design features and the spatial and aesthetic experiences of students. Forty-nine responses were analyzed using an importance–satisfaction analysis (ISA). The gap analysis for all respondents showed significant differences—a significance level of 0.05 between importance and satisfaction—in 31 design attributes in traditional and standardized classrooms. Both the architects and the school educator groups designated five attributes as being of the highest priority for the classroom renovations: ventilation, overall classroom shape, shape of furniture, floor material, and furniture material. Results of these analyses could become considerations for future classroom renovations by local governments to enhance educational environments. In addition, policy recommendations for applying the results of this study to be sustainable classroom renovation throughout South Korea could be an important topic of discussion.

Optimization of dynamic poly-generation system and evaluation of system performance in building application

A decentralized small-scale poly-generation system has attracted lots of attention nowadays. In this study, the poly-generation system is optimized and evaluated for the building application. To reduce the high computational cost of dynamic simulation and multi-objective global optimization process, a hybrid simulation model has been newly proposed. The new hybrid model is developed with the validation and verification of each system component. Based on the developed model, the meta-model is optimized for improving the multi-criteria indices (energy, environment, and economy). For the optimization, the critical design variables are selected as the rated electrical power of the prime mover, the volume of thermal storage system, the cooling/heating capacity ratio supplied by electrically driven systems, and maximum heat power from the storage system. As a result of optimization and decision making, the most effective point from Pareto frontier is determined. In addition, sensitivity analysis and feasibility evaluation are conducted to investigate the effectiveness of the poly-generation system when integrated with the building in South Korea. The results show that primary energy consumption is reduced by 22.9%, CO2 emissions by 14.2%, and annualized total cost by 6.0%, respectively. Through the specific economic investigation, the payback year is calculated as 6.2. Finally, the performance that greatly affects multi-criteria indices is further discussed in terms of utilization rate, load coverage, and self-sufficiency ratio.

Energy performance assessment of HVAC commissioning using long-term monitoring data: A case study of the newly built office building in South Korea

Facing severe climate change, the rapid increase in building energy consumption has become the major challenge and much attention has been paid to reduce energy use by buildings and their components. Among factors relates the building components, HVAC (Heating, Ventilation, and Air-Conditioning) systems, and their operation have accounted for the largest share of total building energy consumption.The present study applied HVAC commissioning to a newly constructed office building in South Korea to investigate the impact on energy consumption. The energy demands for the case building were simulated by using data collected by BEMS and BAS and IPMVP Option D is used to calibrate the conditions of the energy simulation. Utilizing the calibrated energy model, several cases were created and examined to find out the energy effectiveness of the HVAC commissioning. Moreover, the cost-effectiveness of the case building with HVAC commissioning was analyzed.Implementing HVAC commissioning, about 2–6% of the total energy was reduced as per the occupancy rates and the payback period was also calculated. The obtained results of the present study showed the effectiveness of HVAC commissioning and the study can provide information for the development of HVAC commissioning for commercial buildings in Korea.

Evaluation of Energy and Daylight Performance of Old Office Buildings in South Korea with Curtain Walls Remodeled Using Polymer Dispersed Liquid Crystal (PDLC) Films

Globally, energy standards for new buildings are being reinforced to improve energy efficiency, and remodeling policies are being promoted for old buildings. The South Korean Government is promoting green remodeling projects, and focusing on research and product development to improve the performance of old windows and curtain walls. In line with this, the present study proposes two remodeling methods using polymer dispersed liquid crystal (PDLC) films, which can adjust solar radiation for old office buildings. In addition, energy efficiency improvement and daylight performance according to remodeling were analyzed. Attaching PDLC films to the glass of old curtain walls was analyzed; this can reduce heating and cooling energy, reduce the annual discomfort glare occurrence rate, and increase the annual indoor appropriate illuminance ratio. Furthermore, producing a window by laminating a PDLC film between two sheets of glass and putting it over the existing curtain wall was also analyzed; this can reduce annual building energy consumption and the annual discomfort glare occurrence rate, and improve the annual indoor appropriate illuminance ratio. Therefore, PDLC film is expected to be applicable as a next-generation green remodeling material because using it in remodeling can improve energy efficiency of old office buildings and indoor daylight performance.

Evaluation of Effects of the Humidity Level-Based Auto-Controlled Centralized Exhaust Ventilation Systems on Thermal Comfort of Multi-Family Residential Buildings in South Korea

Building air-tightness has been increased to make energy efficient buildings. However, various indoor air quality issues can be caused by high building air-tightness because it allows low air and moisture transmission through building envelop. In order to solve and prevent these issues, mechanical ventilation systems can be used to control the indoor humidity level. The purpose of this paper is to evaluate the performances of the Relative Humidity (RH)-sensor based auto-controlled centralized exhaust ventilation systems to manage indoor air quality and thermal comfort of multi-family residential buildings in South Korea. A series of field tests were performed for different target zones and for various moisture source scenarios. As a result, it was found that the auto-controlled centralized exhaust ventilation systems were able to control indoor air quality and to maintain the zones thermal comfort faster than the baseline cases that did not operate exhaust vents. The results presented in this paper can show the potential and the feasibility of the auto-controlled centralized exhaust ventilation systems for multi-family residential buildings in South Korea. It is expected that the results presented in this paper would be useful for building owners, engineers, and architects when designing building systems.

A Combo Foundation Does the Job: Piled-Raft Foundation Design for a Supertall Skyscraper

Lotte World Tower is a 123-story, 555-m supertall skyscraper with a 6-level basement for retail and car parking located at Jamsil-dong in Seoul, South Korea. (Editor’s Note: For additional information, see “Supertall in Seoul” in the July 2018 issue of CE Magazine, pp. 44-53.) The tower’s footprint is approximately 72 m x 72 m, and its structural form consists of a concrete core wall with eight peripheral 3.5 m x 3.5 m square-shaped mega-columns to resist both the gravity and lateral forces. To enhance structural rigidity, two belt trusses are positioned at levels 218 m and 347 m from the base of the foundation raft. The total serviceability gravity load is around 6,700 MN. The skyscraper opened to the public in April 2017 and is currently the tallest building in South Korea and the fifth tallest building in the world. A structure of such proportions demanded a foundation to resist immense loads and problematic subgrade.

Comparison of Carbon Dioxide Emissions of the Ordinary Reinforced Concrete Slab and the Voided Slab System During the Construction Phase: A Case Study of a Residential Building in South Korea

The construction industry not only consumes a lot of energy but also emits large volumes of carbon dioxide. Most countries have established target reduction values of the carbon dioxide emissions to alleviate environmental burdens and promote sustainable development. The reduction in carbon dioxide emissions in the construction industry has been taking place in various ways as buildings produce large quantities of the carbon dioxide over their construction life cycle. The aim of this study is to assess and compare the carbon dioxide emissions of an ordinary reinforced concrete slab and the voided slab system applied to a case study involving a commercial-residential complex building in South Korea. Process-based life-cycle assessment (LCA) is adopted to compute the carbon dioxide emissions during the construction phase, which includes all processes from material production to the end of construction. The results indicate that the total CO2 emissions are 257,230 and 218,800 kg CO2 for the ordinary reinforced concrete slab and the voided slab system, respectively. The highest contributor to CO2 reduction is the embodied carbon dioxide emissions of the building materials, which accounts for 34,966 kg CO2. The second highest contributor is the transportation of the building materials, accounting for 3417 kg CO2.

Energy Demand Forecast Models for Commercial Buildings in South Korea

With the Paris Agreement entering into full force, South Korea must submit its target greenhouse gas emissions for commercial buildings by 2030 to the United Nations Framework Convention on Climate Change. To determine this target, the annual energy demands must be forecasted through appropriate models; the development of these models is the focus of our study. We developed a system to calculate energy demand forecasts by searching for suitable methods. We built distinct energy forecast models for petroleum, city gas, electricity, heat, and renewable energies. The results show that the most appropriate variable for the petroleum energy model is energy trend. Moreover, the annual increase rate of petroleum energy demand from 2019 to 2030 was forecasted to be −1.7%. The appropriate variable for city gas energy model was the floor area of commercial buildings, which was forecasted to increase at an annual average growth rate of 0.4% from 2019 to 2030. According to the forecast results of energy demand from 2019 to 2030, the annual average growth rates of electricity, heat, and renewable energy demands were 2.1%, −0.2%, and 1.3%, respectively.

Measuring Vulnerability of Typhoon in Residential Facilities: Focusing on Typhoon Maemi in South Korea

Typhoons cause severe monetary damage globally. Many global insurance companies and public agencies are currently developing and utilizing windstorm risk estimation models to calculate the level of risk and set up strategies for avoiding, mitigating, and relocating those economic risks. Hence, the usage and accuracy of the windstorm risk estimation model is becoming increasingly significant, and reflecting local vulnerabilities is essential for refined risk assessment. While key risk indicators have been recognized in practical studies of economic losses associated with windstorms, there remains a lack of comprehensive research addressing the relationship between economic losses of residential buildings for South Korea and vulnerability. This research investigates the real damage record of Typhoon Maemi from an insurance company in order to bridge this gap. The aim of this study is to define the damage indicators of typhoons and create a framework for typhoon damage function, using the damage caused by Typhoon Maemi as a representative paradigm. Basic building information and natural disaster indicators are adopted to develop the damage function. The results and metric of this research provide a pragmatic approach that helps create damage functions for insurance companies and contingency planners, reflecting the actual financial losses and local vulnerabilities of buildings. The framework and results of this study will provide a practical way to manage extreme cases of natural disasters, develop a damage function for insurers and public authorities, and reveal the real economic damage and local vulnerability of residential buildings in South Korea.

Development of a Passive and Active Technology Package Standard and Database for Application to Zero Energy Buildings in South Korea

There is much research on zero energy buildings. In this paper, technologies and policies to improve the building energy efficiency of zero energy buildings are presented. The zero energy building certification system in Korea is introduced, and the evaluation is carried out based on the energy self-reliance rate that enables zero energy buildings. Zero energy buildings are able to minimize energy consumption due to the application of highly efficient building materials and equipment technology. In this research, to increase the prevalence of zero energy buildings in Korea, the authors propose a zero energy building technology package. Using a passive and active technology package, we confirmed the necessity and detailed requirements of each technology parameter. We analyze and classify Korean building material testing methods and performance standards, and propose passive and active technology packages, modules, material performance testing methods and minimum requirement performance standards. Finally, this study proposed a table presenting the test methods, standard and minimum value of performance. By these results, the authors confirmed the effectiveness and availability of passive and active technical packages.

Long-Term Behavior of RC Beams Strengthened with Hybrid Composite Beam

This paper describes the results of long-term tests on reinforced concrete (RC) beams strengthened with hybrid composite beam (HCB) under two different sustained loads. Test specimens were fabricated to reflect the most common RC beam size used in school buildings in South Korea. The specimens had dimensions of 400 mm (width) × 600 mm (depth) × 6000 mm (length), and were tested with or without external strengthening by a hybrid composite beam (HCB). Test results showed that strengthening the RC beams with HCB not only reduced the instantaneous deflection but was also effective in decreasing long-term deflection. In this study, time-dependent factors were investigated using a modified version of the American Concrete Institute (ACI) equation. Time-dependent factors of HCB-strengthened RC beams found in the present work differed from those of other investigations due to various experimental conditions. In the present study, we found that the ACI equation may not provide a reasonable estimation of the long-term behavior of HCB-strengthened RC beams.

Multi-criteria evaluation of medium-sized residential building with micro-CHP system in South Korea

In this study, a medium-sized residential building is analyzed when an internal combustion engine-based combined heating and power (CHP) system is applied. The multi-family building with a floor heating system is selected to represent typical Korean residential situation. Simulation models are developed for the building, prime mover, thermal storage system, and cooling and heating systems. The validated CHP model is integrated to the building, and it is operated with a thermal load following method. The CHP applied residential building model is compared to the baseline model with a grid power and a gas fired boiler system, in terms of energy, environment, and economics. When the CHP system is applied to the residential building in South Korea, total primary energy consumption is decreased by 18.4%, CO2 emissions by 11.8%, and operation cost by 9.6%, respectively. Based on the facility and operating cost, the payback year is calculated as 10.2. In addition, the building performance is further discussed in terms of weather conditions, utility fee change and energy utilization method.

Energy Analysis of 4625 Office Buildings in South Korea

The purpose of the present study was to investigate the relevance of building thermal performance and characteristics to building energy consumption. This paper reports an energy analysis of 4625 office buildings in Seoul, South Korea, using data from the Korean national building energy database and architectural database. The following four research questions were investigated: (1) Do old buildings consume more energy than new ones? (2) Have strict prescriptive building energy codes contributed to the reduction in energy use intensity (EUI, kWh/m2·year) over the past several decades? (3) What are the characteristics of building energy consumption in terms of season, age, and cooling system (electric chiller vs absorption chiller)? (4) Which factors in the Korean building energy database are relevant to building energy consumption? The analyses revealed that, contrary to common assumptions, new buildings did not always consume less energy than old buildings, and it may be wrong to attribute intensification of prescriptive building energy codes directly to building energy efficiency improvements. In addition, the building characteristics (i.e., district, year built, number of floors, number of elevators, and total floor area) available in the Korean building energy database do not adequately explain building energy consumption, and the existing data collection method needs further improvement.

Development of an energy benchmarking database based on cost-effective energy performance indicators: Case study on public buildings in South Korea

The building sector is the largest energy-consuming sector, accounting for over a third of total global energy consumption. In South Korea, approximately 70% of building stock is more than 15 years old and requires appropriate remodeling and/or retrofitting support. Public buildings in particular are targets of legal control to promote energy conservation and value enhancement as examples of best practices to the private sector. Total energy use intensity (EUI), an energy performance indicator, is commonly used to assess the energy performance of public buildings. However, a considerably negative perception has arisen owing to the shortcomings of EUI itself. This study proposes three cost-effective performance indicators designed to resolve this problem and achieve more objective energy performance benchmarking. The indicators focus more on end uses: “cooling,” “heating,” and “base-load.” They are calculated from monthly energy consumption data using an energy disaggregation technique. Benchmarks for the indicators are made based on the datasets of 4,336 public buildings and a benchmarking database is constructed. The database shows that the most important aspect of energy benchmarking for public buildings is the classification of buildings by their similarity.

Energy and economic potential of a concentrated photovoltaic/thermal (CPV/T) system for buildings in South Korea

ABSTRACT In this study, a point focused concentrating photovoltaic (CPV/T) system is built and tested for building integration applications. The main focus of this research is to evaluate the economic viability of a CPV/T system as a replacement of electricity and natural gas for building heating. The performance of a CPV/T system for the top floor apartment heating was analyzed under very cold winter condition of South Korea. The apartment heating load was calculated via the EnergPlus® simulation software. The results show that for some months the CPV/T system can solely meet apartment heating requirements with zero auxiliary energy consumption. By utilizing a CPV/T system for apartment heating instead of using electricity and natural gas, the life cycle savings (LCS) were 2891 $ and 2370 $, respectively. It is also found that by considering 25 years of expected service life of the CPV/T system, its discounted payback period (DPP) based on electricity and natural gas were 12 and 15 years, respectively. It is concluded that the CPV/T system yield the best higher-energy saving efficiency and building heating performance.

Evaluation of the Floor Impact Sound Insulation Performance of a Voided Slab System Applied to a High-Rise Commercial Residential-Complex Building

Multi-unit dwellings, such as apartment housing, town houses, and flats, are some of the most common housing types in Korea, as well as in other countries. Such multi-unit dwellings are considered an effective means to overcome the housing problems of high-density population in urban areas, owing to their high efficiency of land utilisation. However, interlayer noise complaints, such as footsteps or dragging items in apartment housing, are an inevitable problem in apartment dwelling conditions, because each household in an apartment shares walls and ceilings with other households. This paper presents the results acquired from the field test of the floor impact sound insulation performance of a voided slab system as applied to a commercial residential-complex building in South Korea. The results have shown that adopting the voided slab system for a commercial residential-complex building increased floor impact sound insulation performance. The test results show that the sound insulation performance of the voided slab system applied in the building for lightweight and heavyweight floor impact sound reached (47 and 41) dB, respectively. Based on the results of the field tests, it is expected that the application of the voided slab systems to the slabs of the apartment dwellings would be effective, and offer outstanding sound insulation performance. Moreover, it is expected that the floor impact sound insulation performance would be further improved, if the floor finishing materials, such as carpet or other types of flooring material, would first be installed onto the floor.

Assessment of CO2 Emissions by Replacing an Ordinary Reinforced Concrete Slab with the Void Slab System in a High-Rise Commercial Residential Complex Building in South Korea

The purpose of this study is to verify the environmental performance of the novel Void Deck Slab (VDS) system developed by the authors. The proposed VDS is a void slab system with enhanced design features that improve the constructability of the system through the elimination of additional works required to connect the void formers with the anchoring devices. The Life Cycle Assessment (LCA) technique was adopted to assess the carbon dioxide emissions of the void slab system with reference to the ordinary reinforced concrete slab. The system boundary of this study ranged from raw materials to pre-operation phase, in accordance with ISO 14044. The total CO2 emissions of the ordinary reinforced concrete slab and the void slab system were 204,433.06 and 151,754.75 kg CO2-eq, respectively, which equated to about 34% less emissions for the void slab system. In the case of the ordinary reinforced concrete slab, moulds accounted for approximately 62% of CO2 emission, followed by concrete (~34%). The main source of CO2 emissions for the void slab system was concrete that accounted for ~50%, followed by moulds and deck plates that accounted for roughly 27% and 19%, respectively. In the case of the void slab system, void formers would enable a lower amount of concrete, as well as the self-weight of the slab. Besides, although the void formers filled a significant volume of the slab, the contribution to CO2 emissions was less than 1%.

Lessons from the U.S. Building or Structure Fires: Causes and Responses

고양종합터미널 화재, 의정부 오피스텔 화재, 제천 스포츠센터 화재 등 빈번하게 반복되는 다중이용시설 화재사고의 원인과 대응방안에 대한 다양한 분석 및 논의가 진행되어 왔지만, 한국내 많은 복합구조물, 다중이용시설이 유사한 양상의 화재위험에 여전히 노출되어 있다는 사실은 부인할 수 없다. 이러한 후진국형 화재는 미국 등 선진국에서도 과거에 경험했던 것이며, 최근에도 발생하고 있지만, 이러한 화재에 대한 면밀한 분석을 바탕으로 동일한 피해를 반복하지 않으려는 미국 정부와 시민사회의 노력들이 우리에게 시사하는 바가 크다고 할 수 있다. 본 연구에서는 2000년 이후 발생한 미국내 복합건물 화재 사례 다섯건을 현황, 사고원인, 예방 및 대응과정에서의 주요 문제점, 화재이후 법정책 및 사회인식 변화 등을 중심으로 살펴봄으로써 한국 다중이용시설 화재 예방을 위한 정책적 시사점을 도출하고자 하였다. 사례분석을 통해 화재피해 예방 및 대응과 관련된 법령의 정비보다 더욱 중요한 것은 평상시 노후건물을 중심으로 한 스프링클러 등 소방안전시설 구비에 대한 점검 및 철저한 사후조치임이 파악되었고, 이러한 시사점을 한국상황에 맞게 적용함으로써 반복되는 후진국형 화재의 고리를 끊을 수 있는 기반을 마련해야 함을 파악할 수 있었다.Despite sizable efforts on investigating the causes and issues of several fires in multi-use facilities in South Korea, numerous multi-use facilities are still at risk of large-scale fire contributing to substantial fatalities and property damages. Such fire risk is still present in other countries including U.S., but their efforts to avoid similar incidents in future should provide some lessons to policymakers and professionals in fire prevention and management in South Korea. This study examines five fire cases in multi-use buildings in U.S. since 2000, focusing on the case details, main causes and issues in prevention and responses, and the post-incident changes in law, policies, and social perspectives. The lessons from this study is hoped to be adjusted to Korean contexts and fully implemented to refine the prevention and response strategies in response to a growing fire risk on multi-use facilities and buildings in South Korea.

Liberation or purification? Prostitution, women’s movement and nation building in South Korea under US military occupation, 1945–1948

This article investigates postcolonial South Korea’s prostitution policy as a focal point of sexual politics in the undertaking of nation building under US military occupation (1945–1948). It clarifies that the discourse on prostitution served as a forum for competing visions of a new nation: socialism versus nationalism, and women’s liberation versus national purification. It analyzes the paradoxical process by which the women’s campaign to abolish one colonial legacy of prostitution (‘Authorization-Regulation’) eventually resulted in retaining another legacy (‘Toleration-Regulation’) in a new guise. It conceptualizes the postcolonial prostitution policy that combined regulation and prohibition as a ‘Toleration-Regulation Regime,’ arguing that it was a compromise between the US military government and South Korean elites. Finally, this article demonstrates that building the nation was also a process of making female subalterns, prostitutes.