Study On Simplified Calculation Methods For Multi-dependency Network

Network planning technique is always playing an important role in the field of construction engineering. With the projects people facing becoming more and more difficult, the network planning technique has also in unceasingly the evolvement and the improvement. Particularly, dealing with different types of network is convenient with the improvement of computer technology for people. In multi-dependency network, the types of relationship between the front closely activity and the back closely activity were not only finish-to-start relationship with0time difference, but developed finish-to-start relationship with0or more time difference, finish-to-finish, start-to-start, start-to-finish, and mixed logic relationships. The scheduling process for multi-dependency network was similar to that for traditional network. But it had specialness because of time difference.The time differences contain the minimum time difference and the maximum time difference. The minimum time difference means the scheduled time difference between the activity and the back closely activity can not be less than the planned time difference. The maximum time difference means the scheduled time difference between the activity and the front closely activity can not be more than the planned time difference. In real projects, there were many concurrent activities with maximum time differences.This paper introduced the scheduling process and the check rules for multi-dependency network with maximum time difference with examples illustrating. We changed the original network structure by increasing activity amount. We converted multi-dependency network into the traditional network with introducing a new concept—the dummy time difference activity. And then we calculated the time parameters by the equations of schedule calculations for the traditional network and the check rules for the maximum time differences. We found that the time parameters and the critical path was the same as the results by the equations of schedule calculations for the traditional network. In view of this, we can write computer programs to identify the critical path through the network for PERT analysis with this new approach, because it will cost less time for reducing the judgment process of logic relationships, and make a strategic decision for greater efficiency. This simplified method enriched the AON multi-dependency network.