Solutions for technological and economic problems of construction in the case of uncertainty ; Technologinių ir ekonominių statybos uždavinių sprendimas neapibrėžtumo sąlygomis
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2010
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2010
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01 janvier 2010
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VILNIUS GEDIMINAS TECHNICAL UNIVERSITY Darius MIGILINSKAS SOLUTIONS FOR TECHNOLOGICAL AND ECONOMIC PROBLEMS OF CONSTRUCTION IN THE CASE OF UNCERTAINTY SUMMARY OF DOCTORAL DISSERTATION TECHNOLOGICAL SCIENCES, CIVIL ENGINEERING (02T) VILNIUS 2010 Doctoral dissertation was prepared at Vilnius Gediminas Technical University in 2003–2010. The dissertation is defended as an external work. Scientific Consultant Prof Dr Habil Leonas USTINOVI IUS (Vilnius Gediminas Technical University, Technological Sciences, Civil Engineering – 02T). The dissertation is being defended at the Council of Scientific Field of Civil Engineering at Vilnius Gediminas Technical University: Chairman Prof Dr Marija BURINSKIENĖ (Vilnius Gediminas Technical University, Technological Sciences, Civil Engineering – 02T). Members: Associated Prof Dr Stasys Albinas GIRDZIJAUSKAS (Vilnius University Kaunas Faculty of Humanities, Social Sciences, Economics – 04S), Prof Dr Habil Jonas Gediminas MAR IUKAITIS (Vilnius Gediminas Technical University, Technological Sciences, Civil Engineering – 02T), Prof Dr. Habil Friedel PELDSCHUS (Leipzig University of Applied Sciences, Technological Sciences, Civil Engineering – 02T), Dr Zenonas TURSKIS (Vilnius Gediminas Technical University, Technological Sciences, Civil Engineering – 02T).
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Publié par
Publié le
01 janvier 2010
Nombre de lectures
57
Langue
English
VILNIUS GEDIMINAS TECHNICAL UNIVERSITY
Darius MIGILINSKAS
SOLUTIONS FOR TECHNOLOGICAL AND ECONOMIC PROBLEMS OF CONSTRUCTION IN THE CASE OF UNCERTAINTY
SUMMARY OF DOCTORAL DISSERTATION TECHNOLOGICAL SCIENCES, CIVIL ENGINEERING (02T)
VILNIUS
2010
Doctoral dissertation was prepared at Vilnius Gediminas Technical University in 20032010. The dissertation is defended as an external work. Scientific Consultant Prof Dr Habil Leonas USTINOVIČIUS(Vilnius Gediminas Technical University, Technological Sciences, Civil Engineering 02T). The dissertation is being defended at the Council of Scientific Field of Civil Engineering at Vilnius Gediminas Technical University: Chairman Prof Dr Marija BURINSKIENĖ (Vilnius Gediminas Technical University, Technological Sciences, Civil Engineering 02T). Members: Associated Prof Dr Stasys Albinas GIRDZIJAUSKAS (Vilnius University Kaunas Faculty of Humanities, Social Sciences, Economics 04S), Prof Dr Habil Jonas Gediminas MARČIUKAITIS(Vilnius Gediminas Technical University, Technological Sciences, Civil Engineering 02T) , Prof Dr. Habil Friedel PELDSCHUS (Leipzig University of Applied Sciences, Technological Sciences, Civil Engineering 02T), Dr Zenonas TURSKIS Gediminas Technical University, (Vilnius Technological Sciences, Civil Engineering 02T) . Opponents: Prof Dr Birutė GALINIENĖ University, Social Sciences, (Vilnius Economics 04S) , Prof Dr Habil Artūras KAKLAUSKAS(Vilnius Gediminas Technical University, Technological Sciences, Civil Engineering 02T) . The dissertation will be defended at the public meeting of the Council of Scientific Field of Civil Engineering in the Senate Hall of Vilnius Gediminas Technical University at 10 a. m. on 22 September 2010. Address: Saulėtekio al. 11, LT-10223 Vilnius, Lithuania. Tel.: +370 5 274 4952, +370 5 274 4956; fax +370 5 270 0112; e-mail: doktor@vgtu.lt The summary of the doctoral dissertation was distributed on 20 August 2010. A copy of the doctoral dissertation is available for review at the Library of Vilnius Gediminas Technical University (Saulėtekio al. 14, LT-10223 Vilnius, Lithuania). © Darius Migilinskas, 2010
VILNIAUS GEDIMINO TECHNIKOS UNIVERSITETAS
Darius MIGILINSKAS
TECHNOLOGINIŲIR EKONOMINIŲ STATYBOS UŽDAVINIŲSPRENDIMAS NEAPIBRĖŽTUMO SĄLYGOMIS
DAKTARO DISERTACIJOS SANTRAUKA TECHNOLOGIJOS MOKSLAI, STATYBOS INŽINERIJA (02T)
VILNIUS
2010
Disertacija rengta 20032010 metais Vilniaus Gedimino technikos universitete. Disertacija ginama eksternu. Mokslinis konsultantas prof. habil. dr. Leonas USTINOVIČIUS(Vilniaus Gedimino technikos universitetas, technologijos mokslai, statybos inžinerija 02T). Disertacija ginama Vilniaus Gedimino technikos universiteto Statybos inžinerijos mokslo krypties taryboje: Pirmininkas prof. dr. Marija BURINSKIENĖ (Vilniaus Gedimino technikos universitetas, technologijos mokslai, statybos inžinerija 02T) . Nariai: doc. dr. Stasys Albinas GIRDZIJAUSKAS universitetas (Vilniaus Kauno humanitarinis fakultetas, socialiniai mokslai, ekonomika 04S) , prof. habil. dr. Jonas Gediminas MARČIUKAITIS(Vilniaus Gedimino technikos universitetas, technologijos mokslai, statybos inžinerija 02T) , prof. habil. dr. Friedel PELDSCHUS (Leipcigo taikomųjų mokslų universitetas, technologijos mokslai, statybos inžinerija 02T) , dr. Zenonas TURSKIS (Vilniaus Gedimino technikos universitetas, technologijos mokslai, statybos inžinerija 02T). Oponentai: prof. dr. Birutė GALINIENĖ (Vilniaus universitetas, socialiniai mokslai, ekonomika 04S) , prof. habil. dr. Artūras KAKLAUSKAS(Vilniaus Gedimino technikos universitetas, statybos inžinerija 02T). Disertacija bus ginama viešame Statybos inžinerijos mokslo krypties tarybos posėdyje 2010 m. rugsėd. 10 val. Vilniaus Gedimino technikosjo 22 universiteto senato posėdžiųsalėje. Adresas: Saulėtekio al. 11, LT-10223 Vilnius, Lietuva. Tel.: (8 5) 274 4952, (8 5) 274 4956; faksas (8 5) 270 0112; el. paštas doktor@vgtu.lt Disertacijos santrauka išsiuntinėta 2010 m. rugpjūčio 20 d. Disertaciją galima peržiūrėti Vilniaus Gedimino technikos universiteto bibliotekoje (Saulėtekio al. 14, LT-10223 Vilnius, Lietuva). VGTU leidyklos Technika“ 1793-M mokslo literatūros knyga. © Darius Migilinskas, 2010
Introduction Topicality of the problem Inaccuracies, mistakes, unforeseeable circumstances, insufficient (wrong) data management, superficial or inaccurately performed design work, improper management of resources and other issues, which affect the implementation of the project directly or indirectly, can be considered uncertainties in a construction process. A set of such problems may ruin a construction project. To control uncertainties, participants in construction processes apply specialised tools, means and systems such as: automated three-dimensional design, calculation of estimates and resources, management of time planning (scheduling) and resource flows, analysis of implementation and probable risk factors, comparison of alternatives by means of decision support systems. The origins and application of such tools stimulated their continuous improvement and development in construction industry. For instance, a three-dimensional (3D) modelling as a spatial-visual means could have been used as a mere opportunity of imaging; nevertheless, the process of its continuous development turned it into a tool of design and modelling granting the possibility of precise data acquisition. Another example is an estimate providing calculation of preliminary quantities, which indicates an approximate price of a construction project, though it could also be calculated on the basis of precise data from the 3D-model and used for the evaluation and comparison of actual scope of the works accomplished. A timetable serves as another example: it may be treated as a timescale of construction project implementation but it can more effectively be used as a tool of management of construction processes, work organisation and virtual simulation. The analysis of alternatives and probable risks makes up another important example, which can be employed to assess the application of possible alternative solutions prior to the project or in the process of its implementation and to achieve the goals of the project in a more rational, efficient, economic and faster way. The application of the afore-mentioned tools to solve technological and economic problems of construction has to be understood as a particularly relevant issue of construction process management. It is important to join such solutions into a single system and to apply the algorithm of implementation to the solution of construction problems in the case of uncertainty. The object and methodology of the research The object of the research is a set of factors that affect the construction process, its stages and participants, causing uncertainties in dealing with technological and economic construction problems (from theoretical and practical point of view). The data for the research paper and its conclusions was
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obtained by means of expert and comparative methods as well as the analysis of the collected research data such as: publications, textbooks and monographs of Lithuanian and foreign scientists (including the author of the dissertation), manuals, statistical data and information from the Internet, analytical studies conducted in the fields of construction industry and applied mathematics. The thesis assesses and applies the methods of determination of optimal solution and normalisation; it also takes advantage of the major propositions of game theory. Aim and tasks of the work The main aim of this work is to develop a model and methodology of automated management for construction project, which would allow to collect and correct data in the project’ stages, to analyse probable alternatives for reduction of impact from uncertainties and risk factors on the final solution and result of the project. To achieve this aim, the following tasks were set: 1. To analyse the procedures of construction process from the concept stage to facility management and to determine the impact of participants and factors. 2. To analyse and to assess the impact of data accuracy both with variation on different stages of a construction process. 3. and economic problems in construction; toTo analyse technological determine the conditions and situations that cause uncertainty. 4. To find out the dependence between uncertainties and risk. 5. analyse the accuracy of multi-criteria evaluation systems and theTo results of used optimal solutions finding methods with the data processing bias impact on the final solution. 6. model of automated management of a constructionTo develop the project and to evaluate the accuracy of data and benefit from computer-aided (automated) design. 7. To develop a methodology, which would help to reduce and manage uncertainties in technological and economic problems of construction. The scientific novelty and significance The following up-to-date results of the science of engineering were obtained in the process of the thesis: 1. A theoretical model of automated management of a construction project throughout the lifetime of a project (4D PLM), which enables the accumulation and correction of data in the consistent implementation of individual stages of a construction project and the analysis of possible alternatives (by selecting and developing the best alternative) was developed and described.
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2. International survey of professional participants in a construction project was carried out as a part of participation in the international educational Leonardo da Vinci project. The most relevant parts of construction project management and the solutions of improvement of professional competences were determined on the basis of the results of the survey. 3. A unique methodology as a system of products and tools designed for the identification and management of uncertainties in construction activities was developed by means of automated design (modelling) and process simulation. 4. along with examples on uncertainty and riskSpecific proposals management were provided for the solution of technological and economic tasks of construction in order to improve the management of construction project information and to reduce the demand for resources in the implementation of a project. 5. accuracy of indicator values and theThe impact of calculation applied methods of normalisation on the final comparison of alternatives was identified. 6. Analytical model (algorithm) for the analysis of individual alternatives of the stages in a construction project was developed. Defended propositions 1. risk management by means of classification,Uncertainty and identification of sources, assessment of consequences and implementation of systematic means to reduce their impact and costs. 2. Developed complex management of technological and economic problems of construction integrated into the automated design and management system of a building throughout the project life cycle. 3. Automated management model and methodology for a construction project used to accumulate and correct data in the implementation of individual stages of a construction project and to analyse the alternatives of reducing the impact of uncertainties and risk on the final solution and results of a construction project developed. Theoretical and practical use of scientific work 22 scientific articles were published on the topic of the dissertation: one article was published in scientific journals included into theThomson ISI Master Journal List; two articles were published inThomson ISI Proceedings; four in scientific journals cited inISI Proceedingsand IRBdirect, ICONDA
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databases; six articles were published on the international databases approved by the Research Council of Lithuania. The research results of the thesis were published in fifteen scientific conferences in Lithuania, Poland, Latvia, Estonia and Spain. The research data was used in the international educationalLeonardo da Vinciproject. The model developed in the process of research enables other users to conduct the analysis of a construction project throughout its lifetime, provides the opportunity to compare alternatives as well as to select, develop and manage the best of them. The practical sample of application of the proposed methodology and its results is provided in the thesis. Size and structure of the dissertation thesis The thesis consists of the following parts: introduction, 4 chapters, conclusions and proposals, references and annexes. The scope of the dissertation accounts for 160 pages. Chapter I give a general review of global literature on the topic of the thesis and theoretical concepts of uncertainties. Technological and economic problems of construction and the issues of their solution under the conditions of uncertainty are described as the research object of the thesis. Chapter II provides the analysis of the impact of uncertainties on a construction process and the need for their management. Chapter III discusses the means designed for the management of uncertainties in the process of construction. The methodology designed for the solution of technological and economic problems of construction in the case of uncertainty is provided. The implementation stages are presented in great detail. Chapter IV gives a practical example of uncertainty management, it identifies the differences acquired in the comparison of estimate calculations conducted by means of a usual manual way and by means of automated design. Conclusions and recommendations are provided at the end of the thesis. 1. Solutions for problems in the case of uncertainty as the object of research The first chapter describes the research on the experience of the uncertainty management assessment both with economical situations in Lithuanian and other EU countries. It also summarizes the theoretical concepts of risk and uncertainty. It presents a detailed overview of the basic game theory from the definition of matrix games to the description of equilibrium conditions and the saddle points. It provides the description of the calculation of optimal
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strategies according to simple and extended min-max strategy, Wald's, Savage-Niehaus's, Hurwicz's, Bayes-Laplace's, Bernoulli-Laplace's, Hodges-Lehman's and other rules. It also gives the initial presentation of the value’s normalization methods with fully described formulas and assumptions. The impact of information and its management for construction technological and economic problems in the case of uncertainty is also presented. 2. Uncertainty conditions in construction process The second chapter describes the analysis of uncertainty and risk due to implementation of a construction project. The theoretical part describes various definitions of uncertainty and risk both with their sources as calculation bias, information ambiguity and data inaccuracy in construction projects (Fig. 1.). In general, the project's risk or reserve are foreseen in the cost and included into estimate as percentile expression. This decision is not the best solution because the money spent in the beginning of the project design as early problem-solving is 5-10 times more effective than the money spent for actual problem solving in the end (presented in Fig. 1). The main analysis is connected with the project’s appraisal phase and its stages, where the detailed information is the crucial factor for correct decision-making procedures under uncertainty and risk.
Fig. 1.Influence of changes to project cost
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Consequently, different types of risk are presented, which are undistinguishable from uncertainty circumstances in construction. After the description of risk and uncertainty, a list of solutions was prepared. Application of the suggested risk and uncertainty reducing techniques in practise was shown as analysis of precision and bias dependence with available information at different stages of construction project. 3. Uncertainty management in construction This chapter analyzes the uncertainties and possible consequences of the construction project, an attempt to explain the risk management processes and related decisions of the proposals for action to facilitate the construction of the project decision-making under uncertainty. Description of risk and uncertainties can be used as initial tool for uncertainty management. Continuous management leads to preparation of methodology and solutions to ensure acceptable uncertainty management during the entire project life cycle. By summarising all the sources of uncertainties mentioned in the thesis it is advisable to use the following uncertainty management steps as uncertainty management methodology to reduce and control the uncertainties: 1. All decisions must be based on strictly defined by communication procedures, Project language“ requirements with unified working procedures and rules (team collaboration in real and virtual space); 2. Before the initiation of construction works it is advisable to precisely calculate the amounts of works (quantities) by using well prepared 3D models; it will help to avoid consequences due to unestimated work amounts in proposed tendering price, it will reduce the uncertainties that can arise due to unfinished desgn (lack of solutions and detail); 3. Prepared 3D model of building can be used to simulate construction process before the actual start of construction works with possibility to face problems virtually and check the proper planning of works. In construction, it can help to evaluate any changes of the project and to determine possible problems before the consequences occur. 4. The client must choose the contractors with adequate level of knowledge, good experience, sufficient financial-resource capabilities and effectively working software, hardware and machinery. 5. Limits of responsibility must be defined by means of strict contractual obligations. Common problems related with solutions or consequences must be included into a construction contract. It is advisable for a contractor to have long-term contracts with manufacturers, suppliers and subcontractors.
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