为防止直流输电线路在接地极附近发生挖孔桩基础电腐蚀，探讨挖孔桩绝缘施工方法。依托溪洛渡—广东±500 kV同塔双回直流线路工程，对挖孔桩基础对地绝缘和杆塔对基础绝缘的施工工艺做了研究，其中基础对地绝缘施工包括清理基础护壁及垫层、刷底子油、定位弹线试铺、刮油铺玻璃纤维布、浇制2 cm厚砂浆绝缘保护等工艺。同时对基础绝缘施工前的准备工作、施工机具配备、施工材料要求、施工注意事项、施工过程中问题的处理做了较为详细的说明。应用此方法完成基础绝缘施工后，现场检测表明绝缘性能良好。本工艺可以为其他直流输电工程挖孔桩基础绝缘的设计和施工提供参考。

In order to avoid the electric corrosion of digging pile foundation near the grounding electrode of HVDC power transmission line, the insulation construction method for digging pile is researched. According to the requirement of Xiluodu-Guangdong ±500 kv double-circuit DC transmission line project, the insulation construction process between the foundation and the transmission tower, also between the earth and the digging pile foundation are introduced. Then, the reparation work of insulating foundation construction, the construction machines and tools, the requirements of construction material, the matters demanding attentions and the problems solved in the course of construction are introduced in detail. When the insulation construction is completed, the field detection results show that the foundation has been well insulated. The insulation construction technology can be a reference to the insulation design and construction of digging pile foundation of other DC power transmission projects.