• Title/Summary/Keyword: 철근공사

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Determinants of Efficiency of Specialty Construction Companies Using DEA and Tobit Regression Models (DEA와 토빗회귀 모형을 이용한 전문건설기업 효율성 결정요인 분석)

  • Jung, Dae-Woon;Son, Young-Hoon;Kim, Kyung-Rai
    • Korean Journal of Construction Engineering and Management
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    • v.25 no.2
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    • pp.45-55
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    • 2024
  • This study analyzed the efficiency determinants of specialty construction companies by industry using the DEA model and the Tobit model. The analysis targets are 394 specialty construction companies as of 2022. As a result of analysis of efficiency determinants using 12 company characteristics as independent variables, the biggest problem for specialty construction companies was overall efficiency reduction due to rising labor costs. In addition, in a situation where construction companies' loan regulations are severe, the debt ratio was found to have a positive effect on efficiency. Company size had a different impact by industry, and the number of businesses held, credit score, and total capital turnover had an effect only on some industries. This study presents results that are an advance on existing research in that it strategically analyzes factors for improving the efficiency of specialty construction companies. However, it has limitations such as limiting the analysis to only specialty construction companies subject to external audit, insufficient number of companies subject to analysis by industry, and analyzing relative efficiency in the same category for each industry.

Study on Discovery of Vulnerable Factors in Road Tunnels through AHP Analysis (AHP분석을 통한 도로터널의 취약요소 발굴에 관한 연구)

  • Seong-Kyu Yun;Gichun Kang
    • Land and Housing Review
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    • v.15 no.3
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    • pp.177-188
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    • 2024
  • This study aims to identify vulnerability factors through comprehensive safety diagnosis and to seek improvement measures for the safety and maintenance of facilities. In this study, the results of road tunnel inspections and diagnostics were converted into a database (DB). Using this data, we explored to identify vulnerable elements (NATM, ASSM) based on structural types and to develop efficient improvement measures. In this study, we analyzed 76 detailed safety diagnosis reports covering 45 different types of road tunnel facilities. In the detailed guidelines for comprehensive safety diagnosis, the database (DB) items for identifying vulnerable factors were selected by categorizing the basic information, such as the year of completion and damage items. In addition, AHP analysis was conducted separately through experts in related fields to analyze the correlation between damages. As a result, the primary vulnerability factors for NATM and ASSM were identified as cracks, leaks, insufficient lining thickness, and joint rear. ASSM was identified as relatively more susceptible to network cracks and material separation compared to NATM. In contrast, flaking and rebar exposure were interpreted as more significant vulnerabilities for NATM than for ASSM. In addition, the correlation between elements in NATM was found to be low, whereas in ASSM, the correlation between elements was high, indicating a more organic relationship.

A Study on Risk Factor Identification by Specialty Construction Industry Sector through Construction Accident Cases : Focused on the Insurance Data of Specialty Construction Worker (건설재해사례 분석에 의한 전문건설업종별 위험요인 탐색 : 전문건설업 근로자 공제자료를 중심으로)

  • Lee, Young Jai;Kang, Seong Kyung;Yu, Hwan
    • Journal of Korea Society of Industrial Information Systems
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    • v.24 no.1
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    • pp.45-63
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    • 2019
  • The number of domestic construction company is expanding every year while the construction workers' exposure to disaster risk is increasing due to technological advancements and popularity of high-rise buildings. In particular, the industry faces greater fatalities and severe large scale accidents because of construction industry characteristics including influx of foreign workers with different language and culture, large number of aged workers, outsourcing, high place work, heavy machine construction. The construction industry is labor-intensive, which is to be completed under given timeline and consists of unique working environment with a lot of night shifts. In addition, when a fixed construction budget is not secured, there is less investment in safety management resulting in poor risk management at the construction site. Taking account that the construction industry has higher accident risk rate and fatality rate, risky and unique working environment, and various labor pool from foreign to aged workers, preemptive safety management through risk factor identification is a mandatory requirement for the construction industry and site. The study analyzes about 8,500 cases of construction accidents that occurred over the past 10 years and identified risk factor by construction industry sector to secure a systematic insight for risk management. Based on interrelation analysis between accident types, work types, original cause materials and assailing materials, there is correlation between each analysis factor and work industry. Especially for work types, there is great correlation between work tasks and industry type. For reinforced concrete and earthwork are among the most frequent types of accidents, and they are not only high in frequency of accidents, but also have a high risk in categories of occurrence.