Predicting productivity of one or two elevators for construction of high-rise buildings

PREFACE: Examples of material handling systems that require vertical transportation are numerous on construction projects. One such example is that of vertical transportation systems used to transfer materials during the construction of high rise buildings. The optimal design of material handling systems requires careful consideration of the associated waiting and interference problems. The construction manager can schedule and expedite materials and subcontractors on a project, but he cannot altogether prevent waiting since delays can usually be attributed to a series of chance occurrences beyond his control. It is the responsibility of the construction manager who designs the vertical transportation system to evaluate properly the demand for lifting service, to establish the appropriate level of lifting service, to estimate the various costs associated with the satisfaction of demand, and to determine the optimum combination of equipment for the system. It is the purpose of this research to develop mathematical models and analytical procedures which can be useful as the basis for making such decisions.