Research On Uncertainty Of Duration Based On Connection Number

With the rapid growth of the construction and techniques, to strengthen theduration control has become an important work of project management, as well as thequality and cost control. However, duration control is often neglected when constructionproject management focuses on strengthening quality control. Such current situationleads to schedule delays in the actual construction projects prevalently. Not onlyduration control, quality control and investment control of the project could be affectedseriously, but also the unnecessary economic disputes may be caused by poor durationcontrol. Therefore, the change of project duration under the influence of uncertainfactors should be analyzed, and an effective computing models and systems should beestablished to control the project duration better.The duration of project is studied in this paper. Based on the factors that affect theduration and calculate probability of completion of existing achivements, thecategories,the method that using Monte Carlo to simulate the network planning basedon Connect Number is established, which provides the effect weight values, andcalculation methods of various uncertain affects of the duration are studied deeply. Animportant theoretical basis of the duration of uncertainty analysis is proposed. The mainwork is as follow:First, two methods of network planning, those are traditional critical path methodand classic PERT, are summarized, and their principles, advantages and disadvantagesare analyzed. Second, Set Pair Analysis and Connect Number are used to expressuncertainty about the duration. Then Fuzzy Analytic Hierarchy Process is used tocalculated weights for the uncertain factors of the duration. According to theMomentum theory of the Connect Number, the network planning can be judgeddetermined or not. Furthermore, according to the study of the influence of the major uncertainties of duration, the complete probability of network planning under a specificduration, the critical path, the key processes and critical degree could be obtained, andthe transformation process of the critical path can also be explicated. The two methods,Monte Carlo simulation based on Connect Number network planning and Monte Carlosimulation based on traditional PERT network planning, are compared by examples.The result shows that the traditional PERT is improved by the approach with goodreliability. Finally, a construction in progress in Chongqing is chosen as an example totestify the application value of the method in this paper.