• 대한건축학회논문집:구조계
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• 제34권3호
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• pp.95-102
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• 2018

In order to understand interaction between building users' occupant performance and building maintenance performance of maintenance management personnel, actual data from maintenance activities of buildings were analyzed. Also, using building defect customer complaint data reported by building user, satisfaction data on building maintenance services of building users and service response time of maintenance management personnel, a method for evaluating interaction of buildings with the same purpose and same size was proposed. Throughout analysis, average number of occurrences per unit area per year for the mechanical complaints in complex building were presented. In addition, using building users' satisfaction with facility management services, attitude of responding to business obstacles, number of occurrences per unit area per year of mechanical complaints and complaint processing speed, interaction was comprehensively identified and compared.

• 한국신뢰성학회지:신뢰성응용연구
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• 제15권2호
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• pp.90-100
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• 2015

Reliability growth rate (or reliability growth curve slope) have the two cases of trend as a constant or changing one during the reliability growth testing. The changing case is very common situation. The reasons of reliability growth rate changing are that the failures to follow the NHPP (None-Homogeneous Poisson Process), and the solutions implemented during test to break out other problems or not to take out all of the root cause permanently. If the changing were big, the "Goodness of Fit (GOF)" of reliability growth curve to test data would be very low and then reduce the accuracy of assessing result with test data. In this research, we are using Duane model and AMSAA model for assessing test data and projecting the reliability level of complex and repairable system as like construction equipment and vehicle. In case of no changing in reliability growth rate, it is reasonable for reliability engineer to implement the original Duane model (1964) and Crow-AMSAA model (1975) for the assessment and projection activity. However, in case of reliability growth rate changing, it is necessary to find the method to increase the "GOF" of reliability growth curves to test data. To increase GOF of reliability growth curves, it is necessary to find the proper parameter calculation method of interesting reliability growth models that are applicable to the situation of reliability growth rate changing. Since the Duane and AMSAA models have a characteristic to get more strong influence from the initial test (or failure) data than the latest one, the both models have a limitation to contain the latest test data information that is more important and better to assess test data in view of accuracy, especially when the reliability growth rate changing. The main objective of this research is to find the parameter calculation method to reflect the latest test data in the case of reliability growth rate changing. According to my experience in vehicle and construction equipment developments over 18 years, over the 90% in the total development cases are with such changing during the developing test. The objective of this research was to develop the newly assessing method and the process for GOF level increasing in case of reliability growth rate changing that would contribute to achieve more accurate assessing and projecting result. We also developed the new evaluation method for GOF that are applicable to the both models as Duane and AMSAA, so it is possible to compare it between models and check the effectiveness of new parameter calculation methods in any interesting situation. These research results can reduce the decision error for development process and business control with the accurately assessing and projecting result.

• Steel and Composite Structures
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• 제35권1호
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• pp.93-109
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• 2020

Developed from conventional concrete filled steel tubular (CFST) members, concrete-encased CFST has attracted growing attention in building and bridge practices. In actual construction, the inner CFST is erected prior to the casting of the outer reinforced concrete part to support the construction preload, after which the whole composite member is under sustained service load. The complex loading sequence leads to highly nonlinear material interaction and consequently complicated structural performance. This paper studies the full-range behaviour of concrete-encased CFST columns with initial preload on inner CFST followed by sustained service load over the whole composite section. Validated against the reported data obtained from specifically designed tests, a finite element analysis model is developed to investigate the detailed structural behaviour in terms of ultimate strength, load distribution, material interaction and strain development. Parametric analysis is then carried out to evaluate the impact of significant factors on the structural behaviour of the composite columns. Finally, a simplified design method for estimating the sectional capacity of concrete-encased CFST is proposed, with the combined influences of construction preload and sustained service load being taken into account. The feasibility of the developed method is validated against both the test data and the simulation results.

• 한국측량학회지
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• 제30권6_2호
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• pp.623-629
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• 2012

During the construction of crossing engineering one of the important measures to ensure the safety of subway operation is the implementation of deformation surveying to the existing subway tunnel. Guangzhou new subway line 2 engineering which crosses the existing tunnel is taken as the background. How to achieve intelligent and automatic deformation surveying forecast during the subway tunnel construction process is studied. Because large amount of surveying data exists in the subway construction, deformation analysis is difficult and prediction has low accuracy, a subway intelligent deformation prediction model based on the PBIL and support vector machine is proposed. The PBIL algorithm is used to optimize the exact key parameters combination of support vector machine though probability analysis and thereby the predictive ability of the model deformation is greatly improved. Through applications on the Guangzhou subway across deformation surveying deformation engineering the prediction method's predictive ability has high accuracy and the method has high practicality. It can support effective solution to the implementation of the comprehensive and accurate surveying and early warning under subway operation conditions with the environmental interference and complex deformation.

• 국제학술발표논문집
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• The 5th International Conference on Construction Engineering and Project Management
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• pp.87-93
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• 2013

In this research, a new methodology to perform building energy analysis using Industry Foundation Classes (IFC) standard has been studied. With the help of Archicad 14 modeling software, a 3D test model is generated and then exported to IFCXML format. A ruby code program retrieves the building information from the resulting IFCXML file using Nokogiri library. An INP file is created and gets ready for next energy analysis step. DOE 2.2 program analyzes the INP file and gives a detailed report of the energy cost of the building. Case study shows when using the IFC standard method, the Interoperability of the energy analysis is greatly improved. The main stream 3D building modeling software supports IFC standard. DOE 2.2 is able to read the INP file generated by IFC file. This means almost any 3D model created by main stream modeling software can be analyze in terms of energy cost Thus, IFC based energy analysis method has a promising future. With the development and application of IFC standard, designers can do more complex and easy-to-run energy analysis in a more efficient way.

• 한국건설관리학회:학술대회논문집
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• 한국건설관리학회 2008년도 정기학술발표대회 논문집
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• pp.725-728
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• 2008

플랜트 건설공사의 경우 최근 매우 복잡화, 전문화, 대형화되고 있고, 이에 따라 지속적으로 첨단기술접목과 함께 고부가가치 창출이 예상되고 있어 더욱 고도화된 사업관리계획과 더불어 전문인력 양성, 지식정보의 공유가 필수적으로 성장의 기본 요건으로 자리매김하고 있는 추세이다. 이에 따라 본 연구는 플랜트 건설산업의 경쟁력 강화를 위하여 관련 현황을 분석하고, 기업의 특성에 맞춘 유연한 Knowledge Management System(KMS) prototype을 구축, 웹 환경기반의 Portal에 연동한 시스템을 제시하고자 한다.

• 한국건설관리학회:학술대회논문집
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• 한국건설관리학회 2007년도 정기학술발표대회 논문집
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• pp.682-686
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• 2007

건설사업은 다양한 시대적 요구를 충족시키기 위해 매우 다변화되었고, 그에 따라 참여주체들이 많아지고 복잡성이 증가하게 되었으며, 사업의 규모 측면에 있어서도 날로 대형화되어 가고 있는 실정이다. 하지만 현재의 건설 프로젝트 공정관리 수준은 1950년대에 만들어진 PERT나 CPM을 반세기가 지난 지금까지 그대로 사용하고 있을 정도로 후진성을 면치 못하고 있다. 또한 현재의 공정관리는 결과위주의 방식으로 건설사업 과정에서 나타나는 작업 간의 정보의 흐름과 변이요소의 발생을 충분히 고려하지 못하고 있다. 따라서 본 연구에서는 기존의 공정관리도구들의 단점을 개선하고 공정관리기술의 한계를 극복하기 위하여, 국내에는 잘 알려지지 않은 설계관리기법인 DSM(Dependency Structure Matrix)를 도입하여 건설사업 공정관리에 대한 적용성을 고찰해보고자 한다.

• 한국건축시공학회:학술대회논문집
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• 한국건축시공학회 2017년도 춘계 학술논문 발표대회
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• pp.77-78
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• 2017

Although many waterproofing materials and techniques have been developed and applied, there is still a leakage in concrete structures. The main reason for the failure of waterproofing is due to the lack of consideration of the environmental conditions and the inconsistent performance requirement of the waterproofing materials in response to the complexity of the environmental conditions., and materials that are unsuitable to the environment are still being selected for usage due to their low price. Moreover, there is no valid test assessment for waterproofing materials to be used prior to actual application in the construction site. The development of a testing method and apparatus that can evaluate the composite waterproofing method is proposed in this paper and an interpretation method that can analyze the results of the evaluation.

• 한국건설관리학회:학술대회논문집
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• 한국건설관리학회 2004년도 제5회 정기학술발표대회 논문집
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• pp.174-181
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• 2004

국내 최고 높이를 자랑하는 초고층 건물인 타워팰리스 III에 적용된 슈퍼블럭 유닛 커튼월 시공 공법에 대해서 소개한다. 타워팰리스 III는 공기 단축을 위하여, 벨트월 구간의 외주 커튼월을 별도로 후시공하는 Up-Up 공법을 적용하였다. 벨트월 구간의 커튼월을 후시공하는 과정에서 3개층 분량에 해당되는 대형의 커튼월 블럭을 지상에서 선조립한 후에, 타워크레인을 사용하여 한 번에 시공하는 슈퍼블럭 유닛 커튼월 공법을 개발하고 적용하였다. 이 공법의 실현을 위하여 전용의 양중틀을 개발하여 활용하였고, 슈퍼블럭 유닛 커튼월의 시공을 위하여 비워둔 벨트월 상부층의 커튼월을 시공하기 위한 역시공 장비를 개발 적용하였다. 이러한 신공법의 적용을 통하여, 커튼월 시공용 가설 비계의 설치를 생략하였으며, 공기단축과 경비 절감과 같은 경제적 효과 외에도, 안전 확보와 생산성 향상 등의 효과를 얻을 수 있었다.

• Structural Engineering and Mechanics
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• 제55권6호
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• pp.1121-1137
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• 2015

High powered computers and engineering computer systems allow designers to routinely simulate complex physical phenomena. The presented work deals with the analysis of two finite element method optimization techniques (First Order Method-FOM and Subproblem Approximation Method-SAM) implemented in the individual Design Optimization module in the Ansys software to analyze the behavior of real problems. A design optimization is a difficult mathematical process, intended to find the minimum or maximum of an objective function, which is mostly based on iterative procedure. Using optimization techniques in engineering designs requires detailed knowledge of the analyzed problem but also an ability to select the appropriate optimization method. The methods embedded in advanced computer software are based on different optimization techniques and their efficiency is significantly influenced by the specific character of a problem. The efficiency, robustness and accuracy of the methods are studied through strictly convex two-dimensional optimization problem, which is represented by volume minimization of two bars' plane frame structure subjected to maximal vertical displacement limit. Advantages and disadvantages of the methods are described and some practical tips provided which could be beneficial in any efficient engineering design by using an optimization method.