Buffer sizing model with fuzzy assessment on concrete gravity dam and HEPP projects /

Balta, Şemsettin
Timely completion of dam and HEPP projects is indispensable for the country, they are constructed due to economical, political and social consequences of them. Since various uncertainties and variations existed on the construction of dam and HEPP projects because of their complex nature, robust and stable schedules should be created in the beginning of the projects in order to eliminate or minimize the negative effects of them. Among the various techniques; usage of time buffer is considered as one of the most effective methods for the robust and stable scheduling; however, traditional time buffer sizing methods prone from the several deficiencies. The study introduces improved buffer sizing model with fuzzy assessment in order to calculate the sizes of the time buffers more accurately for the concrete gravity dam and HEPP projects by considering the activities’ durations, activities’ characteristics, activities’ interdependencies and project’s characteristics. Fuzzy logic concepts form the main part of the study and Fuzzy Logic ToolboxTM, built on MATLAB, is used in order to develop the model. 89 causes of delay were found for the concrete gravity dam and HEPP projects by making detailed literature review and brainstorming with the experts. Frequency of occurrence and severity values of them were taken into account as inputs for the model. Applicability of the methodology proposed in this study was illustrated in the hypothetical project. Also, by following the methodology proposed in this study; sizes of the time buffers can be calculated for the other types of the projects.


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Citation Formats
Ş. Balta, “Buffer sizing model with fuzzy assessment on concrete gravity dam and HEPP projects /,” M.S. - Master of Science, Middle East Technical University, 2014.