EN
Scheduling projects of linear or repetitive character (roads, pipelines, high-rise buildings) involves harmonizing a number of continuous construction processes to be conducted by specialized crews or machine sets executed at the same time in a number of work sections. Such projects are often modeled by time-distance diagrams that are represented graphically as an X-Y plot where one axis represents location, and the other time. Project planning involves allowing for construction-specific risks and is aimed at providing reliable schedules. These are to help the manager to assure that the project is completed by the predefined due date and, at the same time, that interruptions in work flow are avoided. In the case of repetitive processes, schedule robustness can be improved by providing time buffers between consecutive activities. The paper proposes an analytic method of sizing these buffers that assumes (as in PERT) that activity durations are stochastic variables whose distribution parameters can be defined on the basis of optimistic, pessimistic and most likely estimates. The method was used to construct a casestudy schedule, and the schedule quality was tested by means of simulation.