Project Schedule Control Research Based On Critical Chain

The project in the implementation process, the progress will be affected by many uncertain factors, which will lead to delay of the project. The traditional project schedule management increase much safety time in the process duration to avoid the influence of uncertain factors. This can raise a completion guarantee rate, but can also cause a waste of safety time. The critical chain method is based on the traditional schedule management method, which is considered the resource constraints, and setup the buffer to absorb the uncertainty of process. In order to further consider the influence of various uncertain factors, this paper based on the critical chain method, building a new critical chain schedule management model. This new model makes great progress in the recognition of critical chain, setup of the buffer and the establishment of buffer management mechanism.Specific research work is as follows:(1)The recognition of critical chain. It adopts5.0t as the duration of the process,which can reduce safe time on the premise that given completion guaranteed rate. It considers four objective factors of the tight resource intensity,continuous time, complex procedure, and positional weight and one subjective factor of risk preference level, and analyzes the uncertainty factors of affecting the process. The grey entropy model under resource constraints is established,which can be sorted to balance the resource conflict,and then identify the critical chain.(2)The new setup method of buffer. It includes utilizing consistency standard which is 90% and 50% of the estimated duration’s difference as the safe time,it can ensure that the completion rate of the process in 50%, and the overall project completion rate of 90%. On the basic of RMSE, according to the quantifiable outcomes of uncertainly effective factors, it will revise the safe time so that make sure the initial buffer. The initial FB and the smaller of the last process free float will service as theFeeding Buffer. On the basis of the initial PB,absorbs the remaining buffer of non-critical chain so that it can be make sure the project buffer.(3)The construction of buffer mechanism. According to the effect that consumption will become faster in buffer, it will combine the completion of task chain with the consumption of buffer, ameliorate the traditional tristimulus monitoring method,establish the more realistic buffer management.(4)Case validation. This paper establishes critical chain management model for progress in a middle school project in Langfang, which verifies the feasibility and rationality of the method.On the basis of the original model, this paper establishes the critical chain schedule management model, which can effectively make up some of the defects. It is a powerful tool for project schedule management.