Project scheduling using fuzzy set concepts

Bilal M. Ayyub, Achintya Haldar

Research output: Contribution to journalArticle

75 Scopus citations


Probabilistic methods are being used increasingly in construction engineering. However, when a parameter is expressed in linguistic rather than mathematical terms, classical probability theory fails to incorporate the information. The linguistic variables can be translated into mathematical measures using fuzzy set and system theory. A construction management problem, i.e., estimation of the duration of an activity, is solved using this theory. In order to implement the proposed technique, various membership functions need to be estimated using judgment or with the assistance of experts. The proposed technique is not sensitive to small variations in the membership values. This is a very desirable property. However, the method is sensitive to the choice of the fuzzy relations. The uncertainty in the fuzzy relations can be modeled along with other sources of uncertainty. The mean and variance of the parameters involved in the problem under consideration are estimated here using a new method. The method maximizes the product of the sum of the membership associations for a certain frequency of occurrence and the corresponding frequency of occurrence. One of the main advantages of the proposed technique is that it can be easily implemented in existing computer programs for project scheduling.

Original languageEnglish (US)
Pages (from-to)189-204
Number of pages16
JournalJournal of Construction Engineering and Management
Issue number2
Publication statusPublished - 1984
Externally publishedYes


ASJC Scopus subject areas

  • Strategy and Management
  • Industrial relations
  • Civil and Structural Engineering
  • Building and Construction
  • Industrial and Manufacturing Engineering

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