• Advances in concrete construction
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• 제15권5호
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• pp.333-348
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• 2023

Fast infrastructure development boosts the demand for shotcrete. Despite sand and stone being the most common coarse and fine aggregates for shotcrete, excessive exploration of these materials challenges the ecological environment. This study utilized an industrial solid waste, high-titanium heavy slag, blended with steel fibers to form Wet Shotcrete of Steel Fiber-reinforced High-Titanium Heavy Slag (WSSFHTHS). It investigated its workability, shotcrete performance and mechanical properties under different water-to-cement ratios, fly ash content, superplasticizer dosage, and steel fiber content. The tunnel excavation and support were investigated by conducting finite element numerical simulation analysis and was used in 3 tunnel lining pipes in Zhonggouwan tailing pond. The major findings are as follows: (1) The water-to-cement ratio (w/c ratio) significantly impacted the compressive strength of WSSFHTHS. The highest 28-day compressive strength of 60 MPa was achieved when the w/c ratio was 0.38; (2) Adding fly ash improved the workability and shotcrete performance and strength development of WSSFHTHS. The best anti-permeability performance was achieved when the fly ash constituted 15%, with the lowest permeability coefficient of 4.596 × 10-11 cm/s; (3) The optimum superplasticizer dosage for WSSFHTHS is 0.8%. It provided the best workability and shotcrete performance. Excessive dosage resulted in water bleeding and poor aggregate encapsulation, while insufficient dosage decreased flowability and adversely affected shotcrete performance; (4) The dosage of steel fibers significantly impacted the flexural and tensile strength of WSSFHTHS. When the steel fiber dosage was 45 kg/m³, the 28-day flexural and tensile strengths were 8.95 MPa and 6.15 MPa, respectively; (5) By integrating existing shotcrete techniques, the optimal lining thickness was 80 mm for WSSFHTHS per simulation. The results revealed that after using WSSFHTHS, the displacement of the tunnel surrounding the rock significantly improved, with no cracks or hollows, similar to the simulation results.

• Journal of Construction Engineering and Project Management
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• 제3권3호
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• pp.23-34
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• 2013

As climate change and environmental pollution become one of the biggest global issues today, new renewable energy, especially solar photovoltaic (PV) system, is getting great attention as a sustainable energy source. However, initial investment cost of PV system is considerable, and thus, it is crucial to predict electricity generation accurately before installation of the system. This study analyzes the loss ratio of solar photovoltaic electricity generation from the actual PV system monitoring data to predict electricity generation more accurately in advance. This study is carried out with the following five steps: (i) Data collection of actual electricity generation from PV system and the related information; (ii) Calculation of simulation-based electricity generation; (iii) Comparative analysis between actual electricity generation and simulation-based electricity generation based on the seasonality; (iv) Stochastic approach by defining probability distribution of loss ratio between actual electricity generation and simulation-based electricity generation ; and (v) Case study by conducting Monte-Carlo Simulation (MCS) based on the probability distribution function of loss ratio. The results of this study could be used (i) to estimate electricity generation from PV system more accurately before installation of the system, (ii) to establish the optimal maintenance strategy for the different application fields and the different season, and (iii) to conduct feasibility study on investment at the level of life cycle.

• 국제학술발표논문집
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• The 5th International Conference on Construction Engineering and Project Management
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• pp.375-385
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• 2013

As climate change and environmental pollution become one of the biggest global issues today, new renewable energy, especially solar photovoltaic (PV) system, is getting great attention as a sustainable energy source. However, initial investment cost of PV system is considerable, and thus, it is crucial to predict electricity generation accurately before installation of the system. This study analyzes the loss ratio of solar photovoltaic electricity generation from the actual PV system monitoring data to predict electricity generation more accurately in advance. This study is carried out with the following five steps: (i) Data collection of actual electricity generation from PV system and the related information; (ii) Calculation of simulation-based electricity generation; (iii) Comparative analysis between actual electricity generation and simulation-based electricity generation based on the seasonality; (iv) Stochastic approach by defining probability distribution of loss ratio between actual electricity generation and simulation-based electricity generation ; and (v) Case study by conducting Monte-Carlo Simulation (MCS) based on the probability distribution function of loss ratio. The results of this study could be used (i) to estimate electricity generation from PV system more accurately before installation of the system, (ii) to establish the optimal maintenance strategy for the different application fields and the different season, and (iii) to conduct feasibility study on investment at the level of life cycle.

• 한국강구조학회 논문집
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• 제25권6호
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• pp.649-658
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• 2013

최근 건축 분야에서도 친환경, 순환형 패러다임으로 전환되어지고 있다. 이 연구에서는 사용자의 요구에 따라 구조체의 해체에 의해 재사용이 가능한 구조시스템을 도입하여 건설자재의 절감 및 재활용, 구조체의 장수명화를 통해 친환경 및 $LCCO_2$를 저감할 수 있는 강구조 시스템을 구현하고자 한다. 부재의 재조합이나 재사용을 가능하게 하기 위하여 탈착이 가능한 바닥슬래브와 강재보 접합상세를 제안하고 구조성능 및 진동 등과 같은 동적 특성에 의해 사용성을 파악하고 평가하였다.

• KIEAE Journal
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• 제15권5호
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• pp.67-74
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• 2015

This study aimed to develop a design manual to be used during the initial stage of the nearly Zero Energy Building (nZEB) design process. Recently, with the increased demand for nZEBs, there are many architects and architectural firms who are becoming interested in nZEB design. However, since the nZEB design process requires a different approach to the conventional building design process, architects have difficulties with application of the nZEB design process in their projects. Therefore, a design manual which can be used in the nZEB design process was developed in this study. Based on an intensive literature review, energy-saving strategies and their performance levels, which affect heating and cooling energy consumptions were established for a reference building. To analyze the sensitivity of each energy strategy to the overall performance, computer simulations using EnergyPlus were performed. At the same time, an Analysis of Variance assessment was conducted to estimate the relative importance of each energy factor. The energy sensitivity and priority of the energy factors was developed into a set of design guidelines.

• 의료ㆍ복지 건축 : 한국의료복지건축학회 논문집
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• 제15권2호
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• pp.59-66
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• 2009

The purpose of this study is to define the concept of sustainability, to understand the traditional belief system, to comprehend user-focused healing environment, to understand the current status of Korean Hospitals, to analyze the selected case studies, and to point the way toward enhanced architectural solutions for healing environment in hospitals. The research results indicate that the design of healthcare facilities with healing effects depend on the considerations of 5 senses of patients. In other words, the sustainable design approach to create a healthy healing environment is very important, and architects must be aware of diverse sensory needs of the patients. In addition, the following factors affection healthcare facilities must be considered to create healing environment for users: - "Emphasis on sustainable Design" for harmony among nature, man, and building. - Creation of user Focused Healing Environment reflecting the suers' senses. - Search for New Hospital Forms through various design experiments to create the most suitable healing environment. - "Perception of Paradigm Shift" form a focus on sickness-oriented to wellness-oriented healthcare facility design. - "Awareness of Creating User-Friendly Environment" covering the entire age group form youth to elderly.

• Smart Structures and Systems
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• 제24권6호
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• pp.783-791
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• 2019

Prefabricated reinforced-concrete shear walls are used extensively in building structures because they are convenient to construct and environmentally sustainable. To make large walls easier to transport, they are divided into smaller segments and then assembled at the construction site using a variety of connection methods. The present paper proposes a precast shear wall assembled using steel shear keys, wherein the shear keys are fixed on the embedded steel plates of adjacent wall segments by combined plug and fillet welding. The anchoring strength of shear keys is known to affect the mechanical properties of the wall segments. Loading tests were therefore performed to observe the behavior of precast shear wall specimens with different anchoring components for shear keys. The specimen with insufficient strength of anchoring components was found to have reduced stiffness and lateral resistance. Conversely, an extremely high anchoring strength led to a short-column effect at the base of the wall segments and low deformation ability. Finally, for practical engineering purposes, a design approach involving the safety coefficient of anchoring components for steel shear keys is suggested.

• 국제학술발표논문집
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• The 3th International Conference on Construction Engineering and Project Management
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• pp.276-284
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• 2009

As an on-going research project, Zero Net Energy Test Home (ZNETH) project investigates effective approaches to achieve whole-house environmental and energy goals. The main research objectives are (1) to identify energy saving solutions for designs, materials, and construction methods for the ZNETH house and (2) to verify whether ZNETH house can produce more energy than the house uses by utilizing Building Information Modeling (BIM) and energy analysis tools. The initial project analysis is conducted using building information modeling (BIM) and energy analysis tools. The BIM-driven research approach incorporates architectural and construction engineering methods for improving whole-building performance while minimizing increases in overall building cost. This paper discusses about advantages/disadvantages of using BIM integrated energy analysis, related interoperability issues between BIM software and energy analysis software, and results of energy analysis for ZNETH. Although this investigation is in its early stage, several dramatic outcomes have already been observed. Utilizing BIM for energy analysis is an obvious benefit because of the ease by which the 3D model is transferred, and the speed that an energy model can be analyzed and interpreted to improve design. The research will continue to use the ZNETH project as a testing bed for the integration of sustainable design into the BIM process.

• 국제학술발표논문집
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• The 5th International Conference on Construction Engineering and Project Management
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• pp.437-443
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• 2013

Recently, sustainable building design, a growing field within architectural design, has been emerged in the construction industry as the practice of designing, constructing, and operating facilities in such a manner that their environmental impact, which has become a great concern of construction professionals, can be minimized. A number of different green rating systems have been developed to help assess that a building project is designed and built using strategies intended to minimize or eliminate its impact on the environment. In the United States, the widely accepted national standards for sustainable building design are known as the LEED (Leadership in Energy and Environmental Design) Green Building Rating System. The assessment of sustainability using the LEED green rating system is a challenging and time-consuming work due to its complicated process. In effect, the LEED green rating system awards points for satisfying specified green building criteria into five major categories: sustainable sites, water efficiency, energy and atmosphere, materials and resources, and indoor environmental quality; and sustainability of a project is rated by accumulating scores (100 points maximum) from these five major categories. The sustainability rating process could be accelerated and facilitated by using computer technology such as BIM (Building Information Modeling), an innovative new approach to building design, engineering, and construction management that has been widely used in the construction industry. BIM is defined as a model-based technology linked with a database of project information, which can be accessed, manipulated, and retrieved for construction estimating, scheduling, project management, as well as sustainability rating. This paper will present a framework representing the building knowledge contained in the LEED green building criteria. The proposed building knowledge framework will be implemented into a BIM platform (e.g. Autodesk Revit Architecture) in which sustainability rating of a building design can be automatically performed. The development of the automated sustainability rating system and the results of its implementation will be discussed.

• 의료ㆍ복지 건축 : 한국의료복지건축학회 논문집
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• 제24권4호
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• pp.59-67
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• 2018

Purpose: The concept of the Barrier-Free Design has steadily expanded into a basic principle of design, which can provide safe and convenient lives not only limited to the disables, elders, and pregnant women, but also to all members of the society. This is what we now know as the Universal Design. In other words, Barrier-Free Design for all is Architectural Approach of Universal Design. Thus, as a future-oriented alternative to school facilities according to social change, this study suggests basic direction of school building planning and concept of universal design considering school facilities characteristics. Methods: The characteristics of school facilities are understood from the perspective of Universal Design. In addition, a survey is conducted to identify the current state of school facilities. Result: Findings from this study are as follows. First, Universal Design of School Building is an integrated characteristic. Integration is intended to create and manage an integrated environment instead of an individual and one-time approach to installation and maintenance of convenience facilities. Second, It is a flexible characteristic to be sustainable. In other words, they aim to be selectable to respond to change. Third, It is a characteristic of accumulation of outstanding cases. This means that not only individual schools but also entire school spaces will be applied to Universal Design to form a virtuous circle of environment improvement. Implications: The results of this study may serve as a basic concept in the design of school buildings.