This paper proposes probabilistic damage and collapse models for reinforced concrete poles in electric power distribution networks and investigates the damage and collapse pattern of poles under earthquake excitations. To this end, detailed finite element models of the H-type reinforced concrete poles are developed and verified using past experimental studies as well as the observed damage in previous earthquakes. The models are then subjected to nonlinear static analyses to study the effect of the loading pattern, loading direction, concrete strength, and failure criteria on the capacity and the collapse pattern of the pole. Next, incremental dynamic analysis is carried out to investigate the sensitivity of the seismic response and collapse pattern of the pole to the direction of ground motion, record-to-record variability, and concrete strength. The results show that the damage pattern under static pull tests, which are the only type of the test conducted on such poles, poorly represent the seismic collapse pattern of the pole. The results also reveal that the most vulnerable segment of the pole is the first 0.5 m of the pole above the ground, which can guide the future retrofit strategies. The results of the incremental dynamic analysis are subsequently employed to develop damage and collapse fragility models for 9, 12, and 15 m long poles using the maximum likelihood method. The analysis accounts for the uncertainty not only in the ground motion but also in the material properties of poles. The proposed models make it possible to account for the damage incurred by the power distribution lines in the seismic risk analysis of the power distribution networks as well as the seismic resilience analysis of electrified communities.

本文提出了配电网络中钢筋混凝土杆的概率损坏和倒塌模型，并研究了地震激发下电线杆的损坏和倒塌模式。为此，使用过去的实验研究以及以前地震中观察到的损坏，开发和验证了 H 型钢筋混凝土杆的详细有限元模型。然后对模型进行非线性静态分析，以研究加载模式、加载方向、混凝土强度和破坏标准对杆的容量和倒塌模式的影响。接下来，进行增量动力分析以研究电杆的地震响应和倒塌模式对地震动方向、记录间变化和混凝土强度的敏感性。结果表明，静拉试验下的损坏模式是在此类杆上进行的唯一测试类型，不能很好地代表杆的地震倒塌模式。结果还表明，杆子最脆弱的部分是杆子离地面的前 0.5 m，这可以指导未来的改造策略。增量动态分析的结果随后用于使用最大似然法开发 9、12 和 15 m 长杆的损坏和倒塌脆性模型。该分析不仅考虑了地面运动的不确定性，还考虑了杆的材料特性。