Abstract: The uneven settlement of foundation caused by changes in the surrounding working environment during long-term operation of hydropower station has a significant impact on the safety of the hydro- power structures.Taking a hydropower station project as an example,Midas/GTS NX software is used to establish a three-dimensional finite element model.First,based on actual monitoring data,the forced dis- placement method is used to simulate the uneven settlement of the powerhouse building caused by geological collapse.Second,with the existing settlement,the stress changes of the powerhouse structure under different working conditions are simulated and safety assessment of dangerous components is conducted. Lastly,using uneven settlement as a warning indicator,a safety monitoring and control method is proposed. The research results indicate that the three-dimensional finite element model modified by the forced dis- placement method can meet the safety assessment requirements for hydropower stations with uneven settlement,and can provide reference for the safety analysis and monitoring of hydropower structures

Key words: hydropower station, safety assessment, three-dimensional finite element model, uneven settlement

摘要： 水电站长期运行过程中，周围工作环境改变引起的地基不均匀沉降对水电站结构的安全造成了很大影 响。以某水电站工程为例，利用Midas/GTS NX软件建立三维有限元模型。首先，结合实际监测数据，采用强制位 移法对厂房由于地层塌陷引起的不均匀沉降进行模拟。其次，在该既有沉降的情况下，模拟不同工况水电站厂房 结构的应力变化情况，并对危险构件进行安全评估。最后，以不均匀沉降作为预警指标，提出安全监测控制方 法。研究结果表明：通过强制位移法修正的三维有限元模型可以满足水电站在不均匀沉降下的安全性评估需求， 可为水电站结构安全性分析与监测提供参考。

关键词: 水电站, 安全性评估, 三维有限元模型, 不均匀沉降