International Construction Specialty Conference of the Canadian Society for Civil Engineering (ICSC) (5th : 2015)

Optimizing linear schedule : congestion-minimization approach Esfahan, Nazila Roofigari; Razavi, Saiedeh


Space is a strictly limited resource on a construction site. For linear type of construction projects, the importance of effectively managing space is crucial as their schedules is generated with due consideration to both time and space. As a result, spatio-temporal congestions between activities of these projects could substantially hinder the performance of interfering activities and cause deviations from planned schedules. The existence of such congestions decreases work productivity, and causes accidents to occur. The current literature focuses on minimizing the workspace conflicts in order to perform efficient work and increase productivity. However, the other side of this problem, i.e. the changes in productivities which give rise to such spatio-temporal congestions is overlooked. To tackle this limitation, this paper proposes a constraint satisfaction approach to quantify and minimize potential space-time congestions in the schedules of linear projects using space-time floats. The method is able to detect not only potential conflicts between each activity with its immediate successors, but also any possible conflict between resources of any activity with all other project activities’ throughout the life cycle of the project. In order to optimize the potentially congested schedules in the planning stage, either the range of productivities available to activities are narrowed down, or the overlapped activities are rescheduled to minimize the conflict. A numerical example is analyzed to demonstrate the added benefits of the proposed method.

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Attribution-NonCommercial-NoDerivs 2.5 Canada

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