The decision-making modeling for concurrent planning of construction projects

Concurrent construction, in which multiple construction activities are carried out concurrently or overlapping, is a method developed to reduce time-to-market and increase the value of the project to the owner or user. When overlapping activities, the additional cost for overlap is affected by the interaction between overlapped activities which is affected by the construction work methods used. Thus concurrent planning of construction projects can lead to a benefit for the owner through investigating the interactions between work methods under overlap and finding the best degrees of overlap. However, the determination of the best solution from all the possible combinations of multiple methods and degrees of overlap is affected by the decision-making approach: by a centralized decision-maker (e.g., the project manager) with less accurate information about cost estimates or by a decentralized decision-maker(s) (e.g., subcontractors) with a myopic viewpoint. The objective of this dissertation is to compare the solutions from the two decision-making approaches and to identify the conditions in which one approach is preferred to the other. Thus project owners can benefit from choosing a better approach for concurrent planning under their own conditions. A Monte Carlo simulation model for each decision-making approach was developed: an algorithm for finding the best solution was developed by heuristic methods. Several parameters were incorporated into the models to reflect different conditions for the decision-making approaches: number of activities, number of methods, the project manager’s solution capacity, the uncertainty in the project manager’s knowledge and attitudes towards risk. The comparison of the two approaches was implemented with random cost under different conditions. Furthermore, the model was applied to a hypothetical construction project. From the simulations the major conclusions include: (1) The decentralized approach becomes preferred with more activities; (2) Considering more methods provides more potential for higher benefit to the owner in the decentralized approach; (3) The decentralized approach is recommended under risk-averse attitude and high uncertainty in the project manager’s knowledge.