Development of a grey critical path method for construction planning

A grey critical path method has been developed and applied to a hypothetical case study of construction project planning. The developed method allows uncertain information, presented as interval numbers, to be effectively communicated into the model formulation and the resulting solutions. Thus, construction alternatives can be generated through the interpretation of the solutions (presented as stable intervals) according to projected construction conditions. The output results are capable of reflecting potential system condition variations caused by the existence of input uncertainties. Results from the hypothetical application indicate that reasonable solutions have been generated. A sensitivity analysis of the effects of project completion time variation on system cost has been provided to show the trade-off between time and cost objectives.