水电站厂房的自振频率关乎到其在动力荷载下的安全，在设计阶段加以预测和控制具有重要意义。运用ANSYS有限元软件对水电站厂房进行模态分析，得到厂房结构在一期、二期混凝土及地基的不同材料参数（弹模与容重）下的自振频率，采用基于灰色关联度的系统分析法，确定了水电站厂房自振频率与各主要影响因子的关联性及密切程度。结果表明：只考虑材料弹性模量时，地基弹模对厂房自振频率的影响度最大，其次为厂房一期混凝土弹模和二期混凝土弹模；只考虑混凝土容重时，二期混凝土容重对厂房自振频率的影响度略大于一期混凝土容重；同时考虑厂房混凝土弹模和容重时，结构容重对其自振频率的影响度大于弹模，二者与水电站厂房自振频率的关联度相差甚微。研究成果对控制类似结构的自振频率具有参考意义。

Natural vibration frequency is related to the safety of hydropower stations under dynamic loads. It is significant to predict and control the frequency during the design phase. We performed modal analysis on the hydropower house using the ANSYS finite element software. Thus, we obtained the natural vibration frequency of the structure under the different material parameters (elasticity modulus and bulk density) of the first- and second-stage concrete and the foundation. We estimated the correlation between the structure's natural vibration frequency and the main material parameters using the systematical analysis method based on grey relational grade. The following conclusions were reached. When only the elasticity modulus was considered, the elasticity modulus of the foundation had the largest influence on the natural vibration frequency, followed by the first-stage concrete and the second-stage concrete of the hydropower house. When only the concrete bulk density was considered, the influence of the second-stage concrete bulk density was slightly larger than that of the first-stage concrete. When both elasticity modulus and concrete bulk density were considered, the concrete bulk density had a greater influence than elasticity modulus on the natural vibration frequency of the hydropower station, and their correlations with the natural vibration frequency showed little difference. The research results can provide reference for controlling the natural vibration frequency of similar structures.

国家自然科学基金项目（51579208，51409207，51309190）；中央财政支持地方高校发展专项（106-5X1205）