千丈岩水电站拱坝坝肩抗滑稳定复核分析

Analysis of the Stability against Sliding for Arch Dam Abutments in Qianzhangyan Hydropower Station

千丈岩水电站坝址呈不对称"V"型地形,原设计推荐初步方案为重力坝。通过对"双曲拱坝+左岸重力墩"方案的两岸坝肩存在的地质断层带及裂隙采取工程措施,坝肩及重力墩的抗滑稳定性均可满足规范要求。对"双曲拱坝+左岸重力墩"与重力坝方案进行经济技术比较表明,拱坝经济效益显著。双曲拱坝于2015年建成蓄水,安全监测数据表明,大坝运行情况良好。

The dam site of the Qianzhangyan Hydropower Station is an asymmetric V-shaped valley. The preliminary recommended scheme is a gravity dam, while the new design scheme is a double curvature arch dam combined with the left bank gravity abutment because of the better economic benefit. The stabilities of the arch dam abutments and the gravity abutment against sliding are analyzed. The results show that the stability requirements are satisfied with effective engineering treatment of the geological faults and fractures in the abutments. Practical monitoring data show that the arch dam operates well since the water impoundment in 2015.