• Structural Engineering and Mechanics
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• v.84 no.5
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• pp.699-706
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• 2022

Settlement control techniques are critical for the safety of shield tunnel constructions, especially for facing complex situations. In this study, the shield tunnel structure from Huaita east road station to Heping Road station in Xuzhou metro No.3 line (China) is taken as engineering background, which has various complex problems of the upper-soft and lower-hard composite stratum conditions, twin curve shield tunnels, and underpass the foundation of the piled raft. The deformation characteristics of shield tunnelling passing through buildings are explored. Subsequently, comprehensive research methods of numerical simulation and field measurement are adopted to analyzing the effectiveness of settlement control by using the top grouting technique. The results show that the settlement of the buildings has obvious spatial characteristics, and the hysteresis effect can be obviously observed in soil deformation caused by shield construction. Meanwhile, the two shield constructions can cause repeated disturbances, reducing the soil deformation's hysteresis effect. Moreover, the shield tunnel's differential settlement is too large when a single line passes through, and the shield construction of the outer curve can cause more significant disturbance in the tunnel than the inside curve. Notably, the proposed process control parameters and secondary topgrouting method can effectively control the deformation of the shield tunnel, especially for the long-term deformation.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2021.05a
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• pp.85-86
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• 2021

KPI, an indicator that measures the performance of factors that contribute to achieving strategies of individuals or organizations, is used a lot to analyze the performance of construction work. Construction work consists of individual construction types with different characteristics such as progress method, scale, and input resources, but currently, KPIs for performance analysis of individual construction types are lacking. Therefore, this study aims to obtain and analyze data for establishing construction performance analysis KPIs during construction work to prepare the basis for the creation of future construction KPIs. Preliminary KPIs for earthwork performance analysis selected through this study are expected to be the basis for deriving preliminary KPIs for other individual construction types.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2023.05a
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• pp.407-408
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• 2023

This article proposes a method to assess construction safety risk during the construction phase based on accident loss costs. Risk assessments for hazardous construction work are required by law, but they lack quantitative criteria. To address this, a survey estimated loss costs due to fatalities in the construction industry, finding labor loss cost and delay reimbursement cost to be the largest factors. The proposed method uses algorithm to calculate expected accidents and risk levels based on project characteristics, work methods, personnel, and environment data. This method is expected to enhance the reliability and usability of risk assessments during the construction phase of construction projects.

• Journal of the Korea Furniture Society
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• v.20 no.1
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• pp.21-30
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• 2009

This research is conducted on temporary street furniture, which is one of the significant factors that comprise the street landscape in modem cities. The primary purpose of this research is to present the guidance on direction of planning by examining the design and installation types of construction and screen fences usually established at construction sites for buildings, roads, parks and etc. The results are as follows: 1. The construction and screen fences at construction sites of urban areas used to be a mere tentative facility to prevent noise and safety accidents but have now incremented their roles to serve not only as a functional but also as an aesthetic element with a city view and harmonization with other elements taken into consideration. In particular, it is noticeable that, based on its unique feature of tentativeness, its role has developed to serve as street furniture that adds variability to the modem city. 2. There are two different types of screen fences: blackout type and transparent type. The transparent screen turns out to be used a lot at the construction site of building a skyscraper or differentiated building in downtown city area or in places where there are buildings of similar types and shapes located along the street in the vicinity of the construction site. 3. The actual cases of adopting the tentative construction and screen fences all at the same time as a single unit have been found in historically and culturally significant architectures with the screen design used to demonstrate the view after completion of construction or the characteristics of the architecture.

• Journal of the Korea Institute of Building Construction
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• v.21 no.2
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• pp.157-163
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• 2021

The accident rate is obtained by dividing the number of accidents by the number of regular workers. In the case off construction work, however, the accident rates are not accurately figured out, because they use the approximate number of regular workers, which is estimated based on the amount of construction work and the labor ratio. In addition, the current accident rate estimation method does not reflect the characteristics of construction types, such as building, civil, plant, etc. This study is conducted with the aim of presenting a supplementary method of accident rate assessment that incorporates the characteristics of type of construction. For the purpose of this, correlation and regression analysis are executed to verify the relationships between number of accidents and the amount of construction contract, and several equations are derived which shows the relationship between the number of accidents by accident types and amount of constract by construction types. The result shows that the non-residential work amount and the number of accidents showed a proportional relationship, while the civil work amount and the number of accidents showed an inversely proportional relationship. The results of this research are expected to calibrate the construction accident rates and to be used as an auxiliary indicator to determine the trend of annual accident rates by comparing the values with usual years.

• Journal of Korean Society of Occupational and Environmental Hygiene
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• v.32 no.4
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• pp.456-464
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• 2022

Objectives: The Purpose of this study is to improve work environment measurement in construction industry by survey. Especially, this study focused on the defferences between construction staffs(safety manger, health manager) and work environment measurement institution workers. Methods: Survey targets are construction staffs(safety manger, health manager) and work environment measurement institution workers. Respondent was selected by respective councils and conferences. A questionnaire consisting of items on general characteristics and the improvement of work environment measurement in construction industry. Results: Total of 134 people(39 safety managers, 27 health managers, 68 work environment measurement institution workers) responded to survey. Overall, current work environment measurement was deemed unsuitable for construction industry. There was a significant difference between construction staff and work environment institution workers in some question. On the other hand, there was no noticeable significant difference in general characteristics. Conclusions: As a result of survey, current work environment measurement was deemed unsuitable for construction industry in terms of measurement method, measurement timing, and actual site improvement. In addition, there is a statistically significant differences in response between construction staff and work environment measurement institution workers, so it is necessary to reflect both opinions in order to improve work environment measurement in construction industry.

• Journal of Korean Society of Environmental Engineers
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• v.28 no.1
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• pp.104-110
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• 2006

Growth in population and urbanization has progressively increased the loadings of pollutants from non-point sources as well as point sources. Accordingly, release of contaminants from non-point sources, released with surface runoff of rainwater, is influenced by atmospheric phenomena, geology, and topography. This makes the control of non-point source difficult. Therefore, this study intends to reveal the characteristics of runoff and particle size distribution to observe the fundamental characteristics of runoff. Experiments were carried out at inner road of research center. Average concentration of runoff ranged from 26.8 to 126.4 mg/L for SS and $COD_{Cr}\;15.3{\sim}117.7mg/L,\;TN\;0.07{\sim}5.16mg/L,\;TP\;0.06{\sim}0.49mg/L$ and heavy metals $0.00{\sim}0.29mg/L$. First flush, indicated wash off of pollutant at first rain, was observed for all types of pollutants. Most pollutants revealed a very close correlation with SS ($R^2=0.93{\sim}0.99$). After analyzing characteristics of particle, particle was finer than that from previously examined data.

• International conference on construction engineering and project management
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• 2005.10a
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• pp.768-773
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• 2005

Among various joint ventures, International Construction Joint Ventures (ICJVs) have emerged as a popular approach worldwide to developing large scale projects through international participation. A model, based on economic analysis and represented by several hypotheses obtained from the analysis, will be developed. Furthermore, we will empirically test the hypotheses/model using Structural Equation Model (SEM). This research is expected to explain why there exist different organizational forms for ICJVs, and to develop a framework for choosing appropriate forms with respect to various characteristics of ICJVs.

• Proceedings of the Korean Institute Of Construction Engineering and Management
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• 2006.11a
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• pp.181-186
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• 2006

Estimation based on current data of construction performances have become one of the critical subjects which many researchers have been interested in for the past decades. In order to accomplish accurate measurement and estimation of construction performances, the method of data collection stands the highest priority. However, there are many difficulties in data collection from construction jobsite due to the characteristics of the construction industry. With developments of new technologies in other industries, several technologies has recently initiated to be applied to construction field. Electronic tags based on the identification technology, automatic volume measurement based on laser scanning technology, and Global Positioning System (GPS) have been represented the technologies which show the high opportunity for being used in construction. This study reviews specific aspects of these technologies focused on the utilization in construction jobsite. Also, the challenges which these technologies need to overcome are discussed.

• Journal of the Korea Construction Safety Engineering Association
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• s.36
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• pp.73-81
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• 2006

Construction fall accidents have been investigated by many researchers. Construction workers are prone to fall when elevations of the construction site is high. And falls are the most fatal accidents: it can be directly linked to the death. Construction fall accidents might be reduced by predetermining several areas which are highly probable to have fall accidents and by controlling such areas until the completion of the building construction. In this paper, a fall prevention system is suggested which can identify the areas where the focus on fall protection is perhaps most needed from the process characteristics. Main methodologies for this research are summarized as follows: 1. A data base on elements and types of falls is constructed from the data analysis of last 10 years fall accidents history. 2. Guideline is derived by identifying the highly probable areas of fall accidents with respect to the specific construction process. 3. Developed system is verified by applying the system to construction sites. 4. Finally a fall prevention system is suggested by utilizing the fall accidents data.