Maximum pressure is a crucial factor in pipe break events. In this paper, a field data-based methodology is proposed to statistically investigate the relationship between operating pressures and pipe break rates in water distribution networks. The objective is to develop the pipe break rate functions (BRFs) where a maximum pressure indicator (MPI) is associated with an average level of pipe break rates. The methodology uses measured pressure values at the average zone point to calculate MPIs along with recorded pipe breaks to establish BRFs for different pipe materials. The Bayes theorem is then applied to identify the maximum pressure thresholds on the BRFs by means of the unconditional and break- conditioned cumulative distribution functions of the MPIs. The methodology is applied to a large zone of the water distribution network of Tehran (Iran). The results showed that the annual average of the MPI is the best indicator to develop BRFs. The obtained pressure thresholds confirm that the break rates increase rapidly for specific maximum pressure ranges, which can be used to implement effective pressure management.

最大压力是发生管道破裂事件的关键因素。在本文中，提出了一种基于现场数据的方法来统计研究配水管网中的工作压力和管道破裂率之间的关系。目的是开发管道破裂率函数（BRF），其中最大压力指示器（MPI）与管道破裂率的平均水平相关。该方法使用在平均区域点处测得的压力值来计算MPI以及记录的管道断裂，以建立不同管道材料的BRF。然后，借助MPI的无条件和破坏条件累积分布函数，将贝叶斯定理应用于识别BRF上的最大压力阈值。该方法适用于德黑兰（伊朗）的供水网络的大区域。结果表明，MPI的年平均值是发展BRF的最佳指标。所获得的压力阈值证实了在特定的最大压力范围内，破裂率迅速增加，可用于实施有效的压力管理。