• 제목/요약/키워드: Rework

검색결과 137건 처리시간 0.03초

Identification of Factors Influencing the Operability of Precast Concrete Construction Shipment Request Forms

  • Jeong, Eunbeen;Jang, Junyoung;Kim, Tae Wan
    • 국제학술발표논문집
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    • The 9th International Conference on Construction Engineering and Project Management
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    • pp.145-152
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    • 2022
  • Recently, interest in the precast concrete (PC) construction method has been increasing. The PC construction process consists of i) design, ii) production, iii) transportation, and iv) installation. A PC field manager at the site submits a shipment request form to the factory one to three days before the installation of the PC component. Numerous matters should be considered in writing a shipment request form. Incorrect shipment request forms may cause standby resources, waste of resources, premature work conclusion, or excessive work. These issues can lead to an increase in construction costs, replanning of PC component installation, or rework. In order to prevent such problems, PC component installation should be simulated based on the shipment request form. Accordingly, this study aims to identify factors influencing the operability of shipment request forms for PC construction. To this end, this study derived factors influencing i) initiation of the activity, ii) addition or deletion of activities, and iii) an increase or decrease in the activity execution time. As a result, this study identified flow, the features of PC components, condition of PC components, unloading location, installation location, input equipment and labor, number of anchors, number of supports, weather, strike, and accident. Further studies should verify the factors derived in this study based on focus group interviews.

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Integrating a Machine Learning-based Space Classification Model with an Automated Interior Finishing System in BIM Models

  • Ha, Daemok;Yu, Youngsu;Choi, Jiwon;Kim, Sihyun;Koo, Bonsang
    • 한국건설관리학회논문집
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    • 제24권4호
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    • pp.60-73
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    • 2023
  • The need for adopting automation technologies to improve inefficiencies in interior finishing modeling work is increasing during the Building Information Modeling (BIM) design stage. As a result, the use of visual programming languages (VPL) for practical applications is growing. However, undefined or incorrect space designations in BIM models can hinder the development of automated finishing modeling processes, resulting in erroneous corrections and rework. To address this challenge, this study first developed a rule-based automated interior finishing detailing module for floors, walls, and ceilings. In addition, an automated space integrity checking module with 86.69% ACC using the Multi-Layer Perceptron (MLP) model was developed. These modules were integrated into a design automation module for interior finishing, which was then verified for practical utility. The results showed that the automation module reduced the time required for modeling and integrity checking by 97.6% compared to manual work, confirming its utility in assisting BIM model development for interior finishing works.

NON-VALUE ADDING ACTIVITIES IN SOUTH AFRICAN CONSTRUCTION: A RESEARCH AGENDA

  • Fidelis Emuze;John Smallwood
    • 국제학술발표논문집
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    • The 4th International Conference on Construction Engineering and Project Management Organized by the University of New South Wales
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    • pp.453-458
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    • 2011
  • The construction industry's importance to nation building, economic empowerment, and contributions to global commerce cannot be over emphasised. However, poor productivity, accidents, rework, time and cost overruns, and client dissatisfaction have characterised the industry performance in a multi-dimensional way. The central issue in this particular research is the seemingly inadequate achievement of optimum performance in the construction process, either with respect to value for money for the client and the entire construction supply chain or value in terms of the utility derived from built assets in spite of efforts by government and governmental bodies such as the Construction Industry Development Board (cidb) to increase industry performance. Therefore, based upon an extensive review of related literature, the paper reports on effects and causes of non-value adding activities in the construction industry in general, and South African construction in particular. The research findings indicate that activities that can be referred to as non-value activities are not only prevalent, but they can also be held responsible for performance related issues in terms of cost, time, quality and health and safety (H&S) in construction; and the exploration of pluralism in the research methodology may result in a robust model based upon the system dynamics approach. Therefore, the study suggests that there is major scope for value optimisation in the construction process especially in terms of availability and implementation of interventions, which have not only proven successful in other industries, but are also adaptable in the construction industry context.

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Applying Lean, Green, and Six-Sigma Framework to Improve Exterior Construction Process in Saudi Arabia

  • Banawi, Abdul-Aziz;Bilec, Melissa
    • Journal of Construction Engineering and Project Management
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    • 제4권2호
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    • pp.12-22
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    • 2014
  • Over the last decade, Saudi Arabia has experienced significant economic increases as evidenced by the 30% growth in its gross domestic product; furthermore, the construction industry has increased 10% in the same time period. Due to this significant growth, the construction industry is encountering issues related to construction quality resulting in significant waste and associated environmental impacts. In this research, we applied our previously developed framework that integrates three different methods-Lean, Green, and Six-sigma - to a residential construction complex in Saudi Arabia. Our aim of this case study was to explore the application of the framework in practice to glean quantitative results and further validate the framework. In the case study, we used the developed framework to identify a significant issue related to quality and delays - final completion of 53 residential units was delayed because of failed exterior buildings surfaces. We then used the framework to define the causes behind the defects via a field investigation of the 53 units. Of the defect, construction execution was responsible for 43% of the defect, 31% untrained workers, 19% unfavorable construction weather condition, with 7% accounting for other issues. A procedure was developed in concert with the construction manager and overall developer reducing the amount of rework and waste causes revealed by the field examination and the framework. Although two steps were added to the original construction process to overcome waste causes, still save a lot of resources and reduces environmental impact. In summary, we found that the Lean, Green, Six-sigma framework increased productivity, quality, and reduced waste.

비정형구조의 3차원 좌표제어를 위한 CNC Twisted Tube 공법 적용 -대구 대표물문화관(The ARC)를 중심으로- (CNC Twisted Tube Method for 3D Coordinate Control Technology for Freeform Structure -Focused on The ARC in DaeGu-)

  • 류한국;김성진
    • 한국건축시공학회지
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    • 제13권5호
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    • pp.434-440
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    • 2013
  • 최근 건축은 정형의 건축물의 외관과 설계 범위를 벗어난 비정형의 설계, 시각화, 3차원 모델 구현이 이루어지고 있다. 일반 정형건축물과는 달리 비정형건축물의 지붕과 외벽은 디자인 중심의 외벽시스템과 배수, 방수의 성능을 지닌 지붕마감시스템으로 설계되고 시공되었다. 그러나 비정형 건축물은 외벽과 지붕의 구분이 없어지고 외피로의 개념으로 통합된다. 또한 건축설계의 디자인 트렌드가 정형에서 비정형의 자유로운 형태로 급변하고 있어 각종 현상설계 및 턴키 등 설계경기의 당선을 위하여 비정형의 건축물이 자주 등장하고 있다. 기존 비정형 건축구조물의 곡면외피를 시공하기 위해서는 스틸 각파이프나 C형강으로 비정형 형태를 만들고 거기에 외장을 시공한다. 그러나 이는 공사 기간 지연과 높은 공사비용이 소요되는 문제점이 있다. 제작, 설치, 검측 후 비정형 패널의 부착 오류, 줄눈의 불일치, 곡면의 직선 시공 등의 오류가 매우 빈번히 발생하고 있다. 이에 본 연구는 3차원 좌표제어 기술의 하나인 CNC Twisted Tube 공법을 적용한 구조체의 시공과정을 면밀히 검토하여 3차원 좌표제어 기술로 비정형 건축물의 구현 방안을 제시한다.

설계협업 프로세스의 개선을 위한 CMMI 도입 방안에 대한 연구 (A Study of Introduction of CMMI on Design Process for Improving Collaboration)

  • 전준기;이준성
    • 한국건설관리학회:학술대회논문집
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    • 한국건설관리학회 2008년도 정기학술발표대회 논문집
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    • pp.436-440
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    • 2008
  • 프로젝트 수행시 명확한 업무 프로세스를 정립하고 이의 운영을 평가해 보는 것은 조직의 업무 효율성 향상을 위해 필요하다. 설계사무소 역시 프로젝트 규모의 대형화에 따라 효율적인 프로세스를 적용하여 높은 품질의 성과물을 산출하고 생산성 향상을 추구하는 것이 필요하게 되었다. 이를 위한 한 방안으로 본 논문에서는 설계업무 프로세스 성숙도 평가 체계를 제안한다. SW 개발업체의 역량 성숙도를 평가하기 위해 개발된 CMMI의 프로세스 평가체계를 벤치마킹하여, 설계 프로젝트에 있어서 업무 프로세스 성숙도 평가 체계 구축 방안을 제시하였다. 향후 설계 업무 수행 프로세스 성숙도 평가 체계가 확립된다면, 설계프로젝트의 역량을 높여 설계사무소에는 업무 효율성을, 발주자에게는 만족할만한 품질의 설계 성과물을 가져다 줄 수 있을 것이다.

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Study on System Support for Offshore Plant Piping Process Using 3D Simulator

  • Kim, Hyun-Cheol;Lee, Gyu-Hong
    • 한국해양공학회지
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    • 제34권3호
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    • pp.217-226
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    • 2020
  • An offshore plant is an offshore platform that can process oil and gas resources in rough seas with a poor working environment. Moreover, it is a complex structure with different types of offshore facilities and a large amount of outfitting that connects different offshore installations. In particular, an enormous amount of various piping materials is installed in a relatively narrow space, and thus, the difficulty of working is relatively high compared to working in ships or ground plants. Generally, when the 3D detailed design is completed, an offshore plant piping process is carried out at the shipyard with ISO 2D fabrication drawings and ISO 2D installation drawings. If a worker wants to understand the three-dimensional piping composition in the working area, he can only use three-dimensional viewers that provide limited functionality. As offshore plant construction progresses, correlating work with predecessors becomes more complicated and rework occurs because of frequent design changes. This viewer function makes it difficult to identify the 3D piping structure of the urgently needed part. This study deals with the process support method based on a system using a 3D simulator to improve the efficiency of the piping process. The 3D simulator is based on the Unity3D engine and can be simulated by considering the classification and priority of 3D models by the piping process in the system. Further, it makes it possible to visualize progress information of the process. In addition, the punch content can be displayed on the 3D model after the pipe inspection. Finally, in supporting the data in relation to the piping process, it is considered that 3D-simulator-supported piping installing could improve the work efficiency by more than 99% compared to the existing method.

3D 작업자 시뮬레이션을 이용한 굴삭기 생산공정 작업자 자세분석 (Posture Analysis of Workers in an Excavator Factory Using 3D Human Simulation)

  • 문덕희;백승근;장병림;이준석
    • 한국시뮬레이션학회논문지
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    • 제15권3호
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    • pp.93-101
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    • 2006
  • 근래에 작업자의 근골격계 질환이 산업현장의 주요한 논제로 등장하였다. 이러한 문제를 줄이기 위하여 다양한 방법들이 사용되고 있는데 그 중의 하나가 제품설계, 치구설계, 작업장 설계를 할 때 작업자의 안전을 최대한 확보하도록 설계단계에서 개선을 하는 것이다. 최근에 급속히 발전하고 있는 3D 시뮬레이션 기술을 사용하면 작업장을 설계하는 단계에서 제품 및 치구의 3D 도면을 이용하여 가상의 작업공간을 구축한 후 작업자의 작업 자세를 사전에 검증해 볼 수 있기 때문에 작업장 구축 후 발생할 수 있는 많은 문제점들을 사전에 검증하여 설계실패비용을 최소화할 수 있다. 본 논문은 3D 작업자 시뮬레이션을 이용하여 굴삭기 공장의 특정한 공정을 대상으로 개선 및 최적화를 하기위한 연구다. 먼저 CATIA를 이용하여 제품과 치구 등 작업장 구축을 위한 3D 모델을 개발하였다. 그리고 IGRIP, DPM. Human 등의 개발도구를 복합적으로 이용하여 작업장에서의 작업내용을 시뮬레이션 할 수 있는 모델을 개발한 후 작업 자세에 대한 분석을 수행하였다. 분석결과는 작업장을 개선하는데 이용하였다.

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선체설계와 의장설계간의 정보인터페이스 기법 연구 (Establishment of Information Interface Technology between Hull and Outfitting Designs)

  • 최영태;서흥원;이순섭
    • 대한조선학회논문집
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    • 제50권6호
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    • pp.458-465
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    • 2013
  • Ship design engineering refers to the development and design of shipbuilding architectures in a drawing which reflects all relevant manufacturing processes. This paper provides analysis methods for model-information interfaces between hull structure design and outfitting design, and a technical application for manufacturing phases reflecting the pipe support pad and angle item automatically. The existing information procedure of pipe support pad and angle system processes information using drawing without model specification. Outfitting design team directly distributes drawings to the shop floor then manual-based marking and installation work are conducted refer to the distributed drawings. As a result, this process has become time consuming and causes problems in the productivity and quality improvement due to the rework caused by omitted or incorrect marking. The pipe support pad and angle marking is a method that automatically updates model information to hull structure design using sets of data that analyse the generated model in outfitting design processes. Therefore, this approach provides an efficient solution through design references without manual activities such as a reflection of hull structure design, cutting process, numerical control work, and dimension measurement and marking. The conversion of a method from the existing procedure based on manual marking to the reflective and automatic approach would have enabled to proceed installation work without manual activities for the measurement. Therefore, this research study proposes an efficient approach using pre-data analysis of model information interfaces between design and manufacturing phases to improve productivity during construction for shipbuilding.

곡가공 공정에서 기하학적 접근법에 의한 2차원 성형에 관한 연구 (A Study on Two-Dimensional Forming of Ship Hull Plate by Geometrical Approach)

  • 성우제;안준수;김현욱;나석주
    • Journal of Welding and Joining
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    • 제27권2호
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    • pp.32-37
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    • 2009
  • In shipyard, plate forming is widely used to form the ship hull plate in various shapes. Line heating method by using a flame torch is one of the major shipbuilding processes carried out by skilled workers. Since the forming characteristics depend upon their experiences in manual forming, there are much variations between products and difficulties in communication between engineers and workers. Hence, it needs to develop an automatic forming system which can not only reduce the working time and rework costs but also improve the working environment and hull forming productivity. One of the final goals of plate forming automation is to form a target shape from the initial plate automatically. For automated plate forming, it is required to determine where and how to heat on the plate. To realize this procedure, the inverse problem should be first solved and the effect of curvature shape formed at the heating path should be investigated. In this study, the inverse problem was solved by geometrical approach using the relationship between bending angle and radius of curvature of the curved shape. In addition, experiments of two-dimensional plate forming were performed with the distance-based method considering the curved bending with curvature. The result of the formed shape agreed considerably well with the target shape.