• 제목/요약/키워드: Construction quality control

검색결과 868건 처리시간 0.256초

마이크로웨이브를 이용한 콘크리트 잔골재 표면수율 측정 자동화 (Microwave Moisture Measurement of Fine Aggregate in RMC Industry)

  • 최영철;이봉춘;문규돈;손영정
    • 한국안전학회지
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    • 제27권1호
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    • pp.63-69
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    • 2012
  • Ready-mixed concrete(RMC) has been a major construction materials for infrastructures. However, RMC with poor quality is reported to be social issue since it directly user's safety and convenience. Because the properties of concrete as a construction material are greatly influenced by the variation of water content, to control water accurately is the most efficient method for the quality control in RMC industry. In this study, the automatic measurement technology of fine aggregate was developed by using the microwave moisture measurement. For the various conditions of fine aggregate such as moisture, temperature and pressure, the calibration curve of moisture measurement was obtained by using oven-dry method. From the infield and outfield test, it can be obtained that the accuracy of microwave moisture measurement is very high and the automatic system of microwave moisture measurement is very convenient and useful for quality control in RMC Industry.

트랙터 자동변속기 되먹임 변속 제어기 설계 (Feedback Shift Controller Design of Automatic Transmission for Tractors)

  • 정규홍;정창도;박세하
    • 드라이브 ㆍ 컨트롤
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    • 제13권1호
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    • pp.1-9
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    • 2016
  • Nowadays automatic transmission equipped vehicles prevail in construction and agricultural equipment due to their convenience in driving and operation. Though domestic vehicle manufacturers install imported electronic controlled transmissions at present, overseas products will be replaced by domestic ones in the near future owing to development efforts over the past 10 years. For passenger cars, there are many kinds of shift control algorithms that enhance the shift quality such as feedback and learning control. However, since shift control technologies for heavy duty vehicles are not highly developed, it is possible to improve the shift quality with an organized control method. A feedback control algorithm for neutral-into-gear shift, which is enabled during the inertia phase for the master clutch slip speed to track the slip speed reference, is proposed based on the power transmission structure of TH100. The performance of the feedback shift control is verified by a vehicle test which is implemented with firmware embedded TCU. As the master clutch engages along the predetermined speed trajectory, it can be concluded that the shift quality can be managed by a shift time control parameter. By extending the proposed feedback algorithm for neutral-into-gear shift to gear change and shuttle shift, it is expected that the quality of the shift can be improved.

음용수질 기준과 관리방안 (Recent Development of Drinking Water Quality Standard and its Application)

  • 권숙표
    • 환경위생공학
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    • 제7권2호
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    • pp.83-94
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    • 1992
  • Recently water demand is increasing as the industry prospers. The increase of water demand is followed by the increase of wastewater discharge which pollutes rivers and ground water extensively. These rivers, reservoirs and ground water are sources for drinking water and their contamination affects the quality of water supply and other potable water. In Korea there are 776 water treatment plants which supply drinking water from main rivers or reservoirs. Rivers are the biggest water source for drinking water is being contaminated, the innovation of treatment process is needed. The construction and operation of water supply facilities is under the control of the Ministry of Construction and the water supply offices of cities and provinces. However, drinking water quality is under the control of the bureau of sanitation in the Ministry of Health and Social Affairs. There are 33 items in drinking water quality standards of Korea. Trihalomethanes, Selenium, Diazinone and other three of pesticides have been included lately, The Ministry of Health and Social Affairs is planning to enhance. the level of $VOC_S$(Vola-tile Organic Compounds) standard. Drinking water quality standard is the goal to protect the quality of supply water and ground water. In order to protect the source water from domestic or industrial water, technological improvement and adequate investment should be urgently made. The ultimate goal of drinking water quality is safety and health of consumers. The more stringent the standard are, the better the water quality will be. As the drinking water quality standards become more stringent this year, various and positive solutions by the authorities concerned must be prepared.

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저진동 모래다짐말뚝(LVSCP)의 지반개량효과 분석 (Analysis of Ground Improvement Effect of Low Vibration Sand Compaction Pile Method)

  • 김종국;차준태;이재창;채영수
    • 한국지반공학회:학술대회논문집
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    • 한국지반공학회 2010년도 춘계 학술발표회
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    • pp.1234-1242
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    • 2010
  • In this study, the effect of noise and vibration, and influence of ground improvement are evaluated and its application is analyzed through the example of SCP designed at ground improvement in Song-Do international city. consequently, it showes even comfortable result that it is about 5.0m of inner space, when the LVSCP method is applied, rather than that it is about 30m of inner space when the existing SCP is applied in vibration control standards 2.0mm/sec. In the noise, now that the many differences according to environmental factors like other equipment noise, limited space and so on at the time of the construction by LVSCP method are coming out, so we think that appro itate measures are needed according to surroundings. By the way, when it comes to the estimation of the ground improvement work before and after an improvement of LVSCP method, its result shows that it is satisfacttion to all the standards of compaction control in dregded and reclaimed ground and sedimentary clay layer.

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초고층 주상복합건물의 품질관리 효율성에 관한 연구 (A Study on the Quality Control Effectiveness in the High-rise residential-commercial Complex Building Project)

  • 김석회;임칠순
    • 한국공간구조학회논문집
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    • 제7권4호
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    • pp.79-87
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    • 2007
  • 본 연구의 목적은 초고층 주상복합건물의 품질관리를 통한 시공 분야의 효율성의 특성을 파악하는데 있다. 기존연구에서 시공관련 품질개선요소들이 정리되었으며 규격화된 설문서를 통하여 시공 분야에 있어서 개선요소를 대학원생을 포함한 건축 관련 대학교, 건설회사, 설계사무소등의 실무자들의 의견을 조합하였다. 설문조사 결과와 기존현장 기술자들의 품질관리 인식도를 비교하여 현장별 품질관리의 정량적, 정성적 성과척도를 파악하고 분석하였다.

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중요도-성취도 분석을 이용한 모듈러 건축프로젝트 현장설치 및 양중 단계의 품질 관리방안에 관한 연구 (Assessment of Quality Assurance in the Lifting and Assembly Phase of Modular Construction: An Importance-Performance Analysis Approach)

  • 이정훈
    • 한국건축시공학회지
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    • 제23권5호
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    • pp.595-605
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    • 2023
  • 모듈러 건축 사례가 많아지면서 모듈러 건축에 관한 관심이 높아지고 적용 대상 범위가 확대되고 있다. 모듈러 건축의 장점 중 하나는 공장제작을 통한 우수한 품질의 건축물을 안정적으로 공급할 수 있는 것이다. 이를 위해, 현장 양중 및 설치 단계까지 품질관리를 위한 노력과 방법 적용이 필수적이다. 본 연구는 현재 현장 양중 및 설치 단계에서 품질유지 및 관리에 적용하고 있는 방안들의 중요도와 예방효과를 프로젝트 참여자들을 대상으로 설문조사를 실시하고, 이를 IPA 방법으로 분석하였다. 그 결과, 대부분의 품질 유지 및 관리 방법이 잘 적용되고 있으나, 프로젝트 참여자들간 일부 항목들에 대한 인식 차이가 있음을 확인하였고, 이에 대한 개선방안을 제시하였다. 본 연구 결과는 추후 프로제트 참여자들의 현장설치단계 품질관리 인식개선을 위한 연구에 활용할 수 있다.

공동주택용 외단열 동시타설 공법 적용을 위한 리스크 요인 평가 (Assessment of Risk Factors for Application of Exterior Insulation Board in Cast-in-place Concrete Form System for Apartment)

  • ;김태훈;임현수;조훈희;강경인
    • 한국건축시공학회:학술대회논문집
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    • 한국건축시공학회 2015년도 춘계 학술논문 발표대회
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    • pp.204-205
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    • 2015
  • Exterior insulation board in cast-in-place concrete form system could reduce construction period and improve quality in apartment construction. However, the method is progressed with insulation and concrete frame works at the same time, then risk is increased in duration control and quality management. Therefore, this paper analyzed risk factors through FMEA method. We found that the key risk factors delaying schedule was insulation material that soaked in the rain and quality defects on the insulation material joint. Based on this research, the risk management approach should be developed for improvement of method activation.

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안전사고 예방을 위한 건설업 공정 안전 정보 관리 시스템 개발 (Development of Construction Process Safety Information Management System for Safety Accident Prevention)

  • 전현정;양광모;강경식
    • 대한안전경영과학회지
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    • 제7권1호
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    • pp.11-23
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    • 2005
  • It is difficult to put it into practice in that it requires bearing too much burden to draw out the planning itself in a case of large construction work. Consequently in this paper we select evaluation criteria by construction progress, classify into several categories, and regard potential danger which often occurs, as a evaluation criterion. Further step is to allow workers or collaborated companies to express their expert opinions or experiences and to encourage quality and process control and autonomous safety control by applying PSM(Process Safety Management) method using AHP(Analytic Hierarchy Process) and to development of PSIM(Process Safety Information Management) evaluation method in the construction. The reason why PSIM method should be quantitative and substantial progress is because it contributes Korean constructing companies to enhancing their safety control ability and to taking an equal stance just like developed countries, thereby strengthening their competitive edges.

A MODEL OF CONSTRUCTION WORKER'S PERCEPTIONS ON ELECTRONIC MONITORING

  • Bill L.P. Lee;Stephen Mak
    • 국제학술발표논문집
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    • The 3th International Conference on Construction Engineering and Project Management
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    • pp.190-195
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    • 2009
  • With the growth of information and communication technologies adoption in construction projects, it could be anticipated that more property owners and construction firms will attempt to use electronic gears and gadgets for site monitoring or surveillance purposes. As the construction workers may be the major group of project team members being monitored, from managerial perspectives and for ethical reasons, it is essential to investigate their degree of acceptance on site monitoring systems. Indeed studies on office workplace monitoring suggest that a monitoring system could shape or control the behaviors of employees. With adequate refinements, their research models could be applicable in the construction industry. This paper presents a model for analyzing the antecedences that affect workers' acceptance level on electronic monitoring, and investigating if there is any behavioral change.

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3성분계 중유동 콘크리트의 공학적 특성에 관한 실험적 연구 (An Experimental Study on the Engineering Properties of the Three Components Middle Fluidity Concrete)

  • 김갑수;조봉석;윤종기;윤문기;장종호;김무한
    • 한국건축시공학회:학술대회논문집
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    • 한국건축시공학회 2003년도 학술.기술논문발표회
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    • pp.9-12
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    • 2003
  • High flowing concrete has not spread whole in the normal concrete structure, because it requires special quality control technique. And recently owing to the lack of natural resources and reinforcement of environmental standard, the construction cost of cement is increased rapidly. Also remicon industry has gone through various economical difficulty as the manufacture cost of concrete is increased. So, the purpose of this study is to evaluate the qualities of middle fluidity concrete using the fly-ash and portland blast-furnace slag cement in order to decrease the amount of cement and resolve the problem of the quality control of high flowing concrete and the manufacture cost. The results of this study show that it reduce the amount of addition of superplasticizer and develope properties of concrete to the use the fly-ash and portland blast-furnace slag cement.

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