A construction project composed of a series unique events is a group of given goals set which should be achieved by the limited resources during a certain period. These characteristics of the construction project put forward a number of requirements to project managers, especially in the control of construction time and cost. Fortunately, the network graph provides a reasonable method of project plan to managers. It can display the project activities graphically and describe the priority relationships between activities, which put a great effort for project managers to pay more attentions to the most critical activities. But, there are many uncertain factors affecting the cost and the construction time of the project, which will destroy the normal execution of the original network planning. Therefore, during the actual construction managers have to revise the original network graph repeatedly. Even in some medium scale projects, the production and rapid renewal of project network graph are also very complex, at the same time the time-cost equilibrium has been the most important problem for managers to solve during renewing. To make a rational decision fast, modern computer simulation technology and Nash equilibrium principle are used for analysis and a example demonstrates that this method is feasible.

Time, cost, quality, and safety, with mutual influence, are the four major control items for project management. The best solution for a project is to achieve high quality with low cost in a proper time limit and without safe accident. Based on the comprehensive limitations above, an integrated optimization model is build up, which can balance the construction time-cost-quality-safety systematically in different risk level in order to archive the most satisfactory goals or several approximately perfect plans as alternatives. Through the optimizing the overall economic benefit of construction project is enhanced. Finally an instance, office building project, is carried out to show the validity of the model.