• 제목/요약/키워드: self-construction

검색결과 1,190건 처리시간 0.022초

시멘트계 재료 기반 캡슐을 사용한 자기치유 모르타르의 역학 특성 (Mechanical Properties of Self-Healing Mortar Using Cementitious Material-Based Capsule)

  • 이재인;임수빈;나범수;김채영;윤주호;최세진
    • 한국건축시공학회:학술대회논문집
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    • 한국건축시공학회 2023년도 봄 학술논문 발표대회
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    • pp.149-150
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    • 2023
  • Although concrete is a material widely used in the construction industry, it is very vulnerable to cracking and has a disadvantage in that durability deteriorates when cracks occur. When cracks occur, harmful factors are introduced through the micro-cracks of the structure, reducing durability. Therefore, in this study, as part of a study to alleviate the problems of maintenance and durability deterioration due to cracks in concrete structures, the mechanical properties of self-healing mortar according to the size of the capsule made of cement material were reviewed.

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안전효능감과 산업재해의 관계 분석 (Analysis of the relationship between self-efficacy beliefs and industrial accidents)

  • 이관형;박동현
    • 한국안전학회지
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    • 제14권2호
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    • pp.127-139
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    • 1999
  • Two studies were conducted to examine the relationship between self-efficacy beliefs and industrial accidents. In the preliminary study, focus group interviews were conducted with employees working in manufacturing and construction sector, safety managers, and government officials to understand factors that were associated with industrial accidents. Based on interviews, a questionnaire survey was constructed to assess individual factors (such as self-efficacy beliefs, following safety procedures, life-satisfaction, and stress) that were identified as affecting industrial accidents (such as minor and major accident rates). The questionnaire were administered to a total of 917 respondents (542 employees working in the manufacturing and construction sector, 210 safety managers, and 165 government employee officials overseeing government regulations). The result indicated that three subscales of self-efficacy for employees (self-regulation, enlisting social support, and controlling the environment) were negatively correlated with the company's industrial accident rates. Moreover, those employees with higher self-efficacy were more likely to follow safety procedures and had higher life-satisfaction and lower stress levels. For safety managers, the self-efficacy beliefs were positively correlated with better implementation and higher effectiveness of the educational programs and negatively correlated with their company's accident rates.

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건설업에서 발생하는 근골격계질환 위험요인의 작업자 자가 평가용 체크리스트 개발 (Development of a Self-Administered Checklist for Evaluation of the Musculoskeletal Disorders Risk Factors in Construction Industry)

  • 이윤근;박희석;박정근
    • 대한인간공학회지
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    • 제29권5호
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    • pp.811-818
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    • 2010
  • In this study, a self-administered checklist for evaluation of the musculoskeletal disorders risk factors in construction industry was developed, and its reliability and validity were studied. 10 items of the checklist were determined based on the literature review, and total 2,793 construction workers participated in the analysis of the checklist's applicability. The results from the reliability analysis showed high Cohen's kappa coefficient (0.50~0.77), and high validity was also obtained in terms of relative risk (RR 1.73~9.14). Positive predictability was relatively low (13.0~32.5%), while negative predictability was high (80.1~96.8%). It can be concluded that the checklist would be suitable as a quick filtering tool of the ergonomic risk factors.

자착식 고무화 아스팔트 방수시트의 접착특성에 관한 실험적 연구 (An Experimental Study on the Adhesion Property of Self Adhesive Rubberized Asphalt Waterproofing Sheet)

  • 정현상;강효진;송재영;오상근
    • 한국건축시공학회:학술대회논문집
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    • 한국건축시공학회 2005년도 춘계 학술기술논문발표대회 논문집
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    • pp.1-4
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    • 2005
  • This study is to examine adhesion the characteristics of self adhesive asphalt to minimize of the construction periods and the environmental problems through the performance estimation of materials to reduce waterproof problem and the long durability maintenance of building structures. This study tested the estimation items of self rubberized adhesive asphalt to examine the sheet discovered the most important problem in the construction site and the connection stability in the sheet joint. Besides, this study examined the material characteristics such as tension property, tear property, temperature dependence, heat resistance, adhesion stability and so on. Test results of the separative items satisfied in the reference figure of connection stability and adhesion stability which could confirm adhesion performances and other items also satisfied in the reference.

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Optimization Algorithms for Site Facility Layout Problems Using Self-Organizing Maps

  • Park, U-Yeol;An, Sung-Hoon
    • 한국건축시공학회지
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    • 제12권6호
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    • pp.664-673
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    • 2012
  • Determining the layout of temporary facilities that support construction activities at a site is an important planning activity, as layout can significantly affect cost, quality of work, safety, and other aspects of the project. The construction site layout problem involves difficult combinatorial optimization. Recently, various artificial intelligence(AI)-based algorithms have been applied to solving many complex optimization problems, including neural networks(NN), genetic algorithms(GA), and swarm intelligence(SI) which relates to the collective behavior of social systems such as honey bees and birds. This study proposes a site facility layout optimization algorithm based on self-organizing maps(SOM). Computational experiments are carried out to justify the efficiency of the proposed method and compare it with particle swarm optimization(PSO). The results show that the proposed algorithm can be efficiently employed to solve the problem of site layout.

고강도 Self-Leveling재의 최적 결합재비 (The Optimum Binder Ratio for High-Strength Self-Leveling Material)

  • 김진만
    • 한국건축시공학회:학술대회논문집
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    • 한국건축시공학회 2002년도 학술.기술논문발표회
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    • pp.67-76
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    • 2002
  • Self-leveling material(SLM) is one of the floor finishing materials which make flat surface like as water level by itself in a short time. So it is possible to increase construction speed and enhance economical efficiency. In this study, author intended to develop SLM for the industrial warehouse and factory loading heavy weight machinery and vehicles. The demanded properties for this type of SLM are above 20mm of flow value and above 300kgf/cm2 of 28-days compressive strength. To possess demended strength and fluidity, SLM have to be composed of many types of binders and chemical additives. So it is difficult to decide suitable mixing proportion of composition materials. In this study, author investigated the weight percentage effect of main composition materials for high-strength self-leveling material, by experimental design such as tables of orthogonal arrays and simplex design, and by statistical analysis such as analysis of variance and analysis of response surface. Variables of experiments were ordinary portland cement(OPC), alumina cement(AC), anhydrous gypsum(AG), lime stone(LS) and sand, and properties of tests were fluidity of fresh state and strength of hardened state. Results of this study are showed that suitable mix proportions of binders for the high strength self-leveling materials are two groups. One is 78~85.5% OPC, 7.5~9.5% AC, 9~12.5% AG and the other is 72.5~78% OPC, 9~12.5% AC, 13~l5% AG.

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국가자격증 취득을 위한 효율적 학습요인 연구 - 전공교육과정과 연계한 실내건축기사 국가자격증반 운영을 중심으로 - (Study on Effective Learning Factors to Obtain National Certifications - Focusing on Operation of Interior Architecture Engineers Certifications in Connection with Major Curriculum -)

  • 유용우
    • 한국실내디자인학회논문집
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    • 제23권4호
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    • pp.140-148
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    • 2014
  • The objective of this study is to address Effective Learning Methodology by subjects to acquire National Certification which is an essential requirement to get employed. For this purpose, analysis was completed after conducting a survey on the class to obtain Interior Architecture Engineer Certification. 23 applicants were selected based on effectiveness of each subject, level of difficulty, degree of understanding, mentoring effect, self-driven learning, and group discussion. Results are as below. Upon the first written test, Interior Design Theory and Chromatics showed a high learning effectiveness in self-driven learning and mentoring. Ergonomics showed a high learning effectiveness in mentoring, self-driven learning and group discussion while Building Materials, Architecture Construction presented a high effectiveness only in mentoring and group discussion. Architecture Environment showed average learning effectiveness in mentoring and group discussion and showed a low effectiveness in self-driven learning. Upon the second practice test, Interior Architecture Construction and Planning/Management of Construction Materials presented an average learning effectiveness in mentoring and group discussion. Process Control and Adding Up(Supply Calculation) showed a low learning effectiveness in self-driven learning and presented an average to below average learning effectiveness in mentoring and group discussion. Lastly, Interior Design Plan, Interior Design Drawings presented average learning effectiveness in mentoring and group discussion however they showed a high effectiveness in self-driven learning.

글라스 버블을 사용한 자기 충전 콘크리트의 레올로지 특성에 관한 연구 (Study on Rheological Characteristics of Self-Compacting Concrete using Glass Bubble)

  • 이한용;윤섭;서태석
    • 한국건축시공학회:학술대회논문집
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    • 한국건축시공학회 2017년도 추계 학술논문 발표대회
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    • pp.73-74
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    • 2017
  • In this study, unlike high flowing concrete, using glass bubble to develop self-compacting concrete(hereinafter referred to as "SCC") with excellent filler performance by evaluating both flowability and yield stress, viscosity An experiment was conducted. Experimental results show that when 1 kg of glass bubbles are used, it is effective in stabilizing the physical properties of concrete, reducing the yield stress and viscosity.

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비정질금속섬유 보강 자기치유 모르타르의 역학 및 내구특성 (Mechanical and Durability Characteristics of Amorphous Metallic Fiber Reinforced Self-Healing Mortar)

  • 윤주호;이민욱;김채영;이재인;최세진
    • 한국건축시공학회:학술대회논문집
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    • 한국건축시공학회 2023년도 가을학술발표대회논문집
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    • pp.27-28
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    • 2023
  • This study compared and analyzed the fluidity, compressive strength, and carbonation resistacne of amorphous metal fiber reinforced mortar according to the PCC mixing ratio as part of a study to improve the self-healing performance and tensile performance of concrete structures.

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Job Training and Safety Education for Modular Construction using Virtual Reality

  • Choi, Hyeongho;Chae, Jeonghyeun;Kang, Youngcheol
    • 한국건설관리학회논문집
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    • 제24권5호
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    • pp.63-72
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    • 2023
  • This study investigates the virtual reality (VR) simulation to train construction workers for modular construction. Recently, the construction industry has been experiencing a growing demand for modular construction due to a shortage of labors and an increasing social need for safety. While the demand for modular construction has been increasing, construction labors suffer a basic knowledge regarding modular construction. The users of the simulation, developed by Unity program and Oculus Quest 2, experience the removal of hazardous elements at the location whether the modular unit suspended by a crane is lowered, the lowering and assembly of units through crane operation, and the fall from the roof which is the most frequent accidents in modular construction. The simulation was tested by 15 subjects. The effectiveness of the education was measured through a survey on self-efficacy, perceived usefulness, usability, and presence. It was found that the VR training is suitable for educating on the modular construction activities and safety issues related to them. This study also found that perceived usefulness is the factor that has the greatest impact on self-efficacy. This study can contribute to resolving the labor education issues for the deployment of modular construction.