• Proceedings of the Korean Institute of Building Construction Conference
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• 2023.05a
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• pp.197-198
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• 2023

This study was conducted as part of research and development of high-strength grout. Accordingly, dolomite aggregate was used as a filler incorporated into the high-strength grout. Dolomite aggregate has a disadvantage of increasing the viscosity of the grout due to higher generation of fine powder than other aggregates. Accordingly, in this experiment, it was confirmed that the viscosity, flow time, and flow of high-strength grout change according to the volume composition ratio of dolomite aggregate and cement-based material. All experiments were conducted based on the Korean Industrial Standard KS F 4044, and the mixing factor was applied according to the composition ratio of the binder and the filler. In the experiment, the amount of fine powder contained in the dolomite aggregate rather than the silica sand used in the past is grasped, and after mixing with the grout accordingly, the mixture is proceeded to measure the viscosity in an unhardened state. In addition, the flow and flow time of the grout are evaluated according to the viscosity. As a result of the experiment, it was confirmed that the viscosity and flow time decreased and the flow increased as the volume composition ratio of the dolomite aggregate to the cement-based material increased.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2023.05a
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• pp.311-312
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• 2023

In this study, porous concrete with improved functionality was developed by using superabsorbent polymer (SAP) to provide rooting space for plants. The depth of settlement and mass change according to the substitution and addition rate of SAP were determined by investigating the functional performance of SAP and the volume change upon saturation. Test results indicated the depth of penetration settlement increased as the substitution rate of SAP increased, but the mass change could not be confirmed as the addition rate of SAP increased. The instability of the specimens due to the excessive volume change of SAP, as well as the osmotic pressure phenomenon according to the pH concentration, were identified as the cause. Therefore, future studies are needed to investigate the appropriate substitution and addition rate of SAP, as well as to reduce the osmotic pressure phenomenon according to the pH concentration, which would contribute to the improvement of the functional performance of vegetation concrete.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.30 no.3C
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• pp.167-174
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• 2010

In this study, numerical analysis has been performed to compare the ground movements in a single ground layer and multiple ground layers due to nearby tunnel excavation. The numerical analysis has been conducted in the different ground layer conditions considering different construction conditions (volume loss at excavation face), and the results of the maximum surface settlement and horizontal displacement have been compared considering the ground layer and construction conditions. In addition, the maximum surface settlement from the numerical analysis has been compared with the maximum settlement at tunnel crown considering the ground layer and construction conditions, and the maximum surface settlement has been also compared with the maximum horizontal displacement with the ground layer conditions. Besides, the volume loss($V_L$) at tunnel excavation face has been compared with the total surface settlement volume($V_s$) with the variation of ground layer condition. The results from the numerical analysis have been compared with field measurements and by this comparison it is believed that the numerical results in this study can be utilized practically in analyzing the nearby ground behavior in different ground layer and construction conditions due to tunnel excavation.

• Proceedings of the Korean Institute Of Construction Engineering and Management
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• autumn
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• pp.88-95
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• 2003

A firm's business composition and the sales volume of each business segment are subject to change depending, to a considerable extent, on the firm's business strategy. These changes were weighted and represented as a single index, referred to by scholars in strategic management and industrial organization research fields as 'firm entropy' then its impact on firms' profitability was assessed over twelve years. The performance differences between contractor and non-contractor firms, as well as focused and diversified firms, were compared through a Longitudinal Data Analysis Technique within a Hierarchical Linear Modeling framework. Hypothesis was formulated based on firm diversification theories and previous research findings. The hypothesis was tested according to the modeling outcomes, and implications are presented. The research findings indicate that the level of firms' long-term profitability supports the argument that the construction industry is highly competitive and mature.

• Journal of Fashion Business
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• v.18 no.1
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• pp.164-181
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• 2014

As the boundary between fashion and architecture is getting blurred, the interactions of the two fields are turning out abundant as well as essential. This study investigates the tectonic strategies in architectural fashion design as a novel aesthetic in the 21st century by combining literary survey and case analysis on architecture and contemporary fashion. The tectonic strategies in the works of architectural fashion designers were categorized as follows: organic geometry, technological garment construction, and independent space. Organic geometry transforms basic geometric shapes into subtle organic forms after being thrown on the body. Technological garment construction explores the garment structure and volume by applying the structural principle of suspension and fractal geometry. Independent space refers to maintaining the firm three-dimensionality of garment structure which keeps the distance from the body, assuming the similarity to architecture.

• Journal of Fashion Business
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• v.21 no.3
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• pp.1-13
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• 2017

Ralph Rucci, the first American designer who presented official collections at Paris Couture since Mainbocher, is known for his innovative dressmaking techniques and sculptural forms. Accompanied by literature survey, this study examines the aesthetics of Ralph Rucci's designs by content analysis of his works, Rucci's designs since his debut collection of 1994 until he left the Chado Ralph Rucci label in 2014 and his returning collection under the new label, RR331, in 2016. Ralph Rucci developed his creative designs by the following strategies: First, he reinvents the couture tradition of Balenciaga and $Gr{\grave{e}}s$ into progressive and functional American couture in that he gives consideration to a wearer's movements and comforts. Second, Rucci constructs architectural volume based on human anatomy and architectonic strategies, with the attention to three-dimensional quality of the space built between the body and a garment. Third, he conducts engineered construction summarized by his original 'suspension' techniques, which function as both ornamentation and construction.

• Journal of Korean Society for Atmospheric Environment
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• v.29 no.6
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• pp.773-779
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• 2013

This study was performed to provide the basic data for the function of BTEX removal for compact electrostatic precipitator which are applicable to indoor environment (or closed spaces). For this purpose, the adsorption equilibrium test was conducted for BTEX of activated carbon sheet (ACS) and activated carbon (AC), and the adsorption characteristics of AC and ACS were evaluated using the Langmuir constant which was obtained from the adsorption characteristics, adsorption capacity and regression calculation. The surface area and adsorption pore volume of ACS reduced by 70% and 86%, respectively, as compared to those of AC, and the adsorption capacities of BTEX also showed a similar level. Thus, it is considered that ACS applied electrostatic precipitator is able to remove dust and BTEX simultaneously.

• Computers and Concrete
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• v.22 no.1
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• pp.117-122
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• 2018

The use of nanotechnology materials and applications in the construction industry should be considered for enhancing material properties. However, in this paper, the technical and economical assessment of applying silica nanoparticles for construction of concrete structure is studied. In order to obtain the equivalent material properties of the structure, the Mori-Tanaka model is used considering agglomeration of nanoparticles. The effect of using these nanoparticles on mechanical properties of concrete, such as the modulus of elasticity, compressive strength, as well as its indirect effect on armature percentage is investigated. Finally, the price of silica nanoparticles and its effect on the price increase of concrete structure is investigated. The results show that increasing the volume percent of silica nanoparticles up to 10% improves elastic modulus 111% and reduces amateur percentage up to 72%.

• Proceedings of the Korea Concrete Institute Conference
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• 2003.05a
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• pp.65-68
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• 2003

This study is intended to look into the influence of environment and construction factor on bleeding of concrete. According to the results, as wind is light, relative humidity is high and temperature is low, the amount of bleeding increases greatly, and evaporation speed is influenced greatly by order of wind, temperature and humidity. As the properties of bleeding by construction factor, the amount of bleeding increases with an increase of placing thickness, but the bleeding ratio, the amount of bleeding per unit volume, increases with a decrease of the placing thickness. Bleeding speed is fastest at about 90 minute after placing concrete. Also, as wind is light, relative humidity is high, temperature is low and the placing thickness is thick, bleeding speed grow faster.

• Journal of the Korea Institute of Building Construction
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• v.8 no.3
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• pp.119-125
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• 2008

The volume of material and number of workers mobilized has been on the rise in line with the domestic projects getting higher, larger and complex currently. Particularly for the project in downtown, delivering the resources in timely manner is very crucial in carrying out the overall project as scheduled. Inappropriate lifting plan often causes inefficiency over the entire project, resulting in increase in schedule and cost. Despite of such importance of lifting plan for architectural work, lifting plans at the most of domestic projects, except a few cases for large scale high-rise buildings, have been heavily dependent on engineer's personal experience and intuition alone. To deal with such problems, the study was intended to develop and suggest a systematic and objective process for determining the lift, categorizing the lifting equipment into the two types, one for workers and another for material.