水利水电施工搭接网络进度风险计算

搭接进度网络可替代双代号和单代号进度网络而得到广泛应用，但PERT方法并不适用于搭接进度网络，因此搭接进度网络风险计算有待探讨。本文将搭接进度网络相邻两工序的时距假设为工序，并称其为时距工序，然后使其转化为广义PERT网络。在此基础上，首先提出了用MC(Monte Carlo)方法计算施工搭接网络进度风险的步骤和方法。其次针对MC(Monte Carlo)方法和经典PERT计算进度风险的不足，提出了修正PERT计算施工搭接网络进度风险的方法。将MC方法和修正PERT方法应用于工程实例，取得了满意的结果。

Risk calculation of precedence network schedule for hydraulic projects

The Precedence Network (PN) can substitute the Activity-on-Arrow Network and the Activity-on-Node Network. Because PERT is not suitable for PN, so the schedule risk calculation of PN is to be discussed. In this article, the lag between two adjacent working procedures in PN was hypothesized as the Working Procedure, named as Lag Procedure. Then, PN can be transformed into the general PERT. On this basis, the steps and method of calculating schedule risk of PN by MC (Monte Carlo) method was put forward. The modified method PERT in calculation schedule risk of PN was put forward. Satisfactory results will be obtained when the MC method and the modified PERT method are put into practice.