State Key Laboratory of Hydrology-Water Resources and Hydraulic Engineering, Hohai University, Nanjing, 210098, China.
College of Water Conservancy and Hydropower Engineering, Hohai University, Nanjing, 210098, China.
Sci Rep. 2022 May 26;12(1):8913. doi: 10.1038/s41598-022-13073-9.
The Foziling multi-arch dam, one of the few multi-arch dams in the world, was built on the bedrock with complicated geological conditions. It has undergone several reinforcements since it was put into service in the 1950s. In this study, the dam safety is evaluated by analyzing the measured displacements and simulating stresses in the concrete. Firstly, the multiple linear stepwise regression (MLSR) is used to train and test the relationships between the loads and displacement based on the hydrostatic-temperature-time (HTT) model. Subsequently, the contributions of water level, temperature, and time to displacements are determined, and the influence characteristics of water level and temperature on displacements are interpreted. Finally, the dam stress state is evaluated by establishing a dam finite element model and simulating the stress distribution in various operating conditions. The results indicate that (1) the dam is currently in an elastic state after the last reinforcement; (2) temperature contributes the most to the displacement, and the drastic fluctuation of temperature is the disadvantage factor for multi-arch dam safety; (3) the stresses generally can meet the requirements of code; and (4) the ideas and methods of the study can provide references for the safety evaluation of other concrete dams.
佛子岭连拱坝是世界上少数几座连拱坝之一，建在地质条件复杂的基岩上。自 20 世纪 50 年代投入使用以来，该坝经历了多次加固。本研究通过分析实测位移和模拟混凝土中的应力，对大坝的安全性进行评估。首先，基于静水-温度-时间（HTT）模型，采用多元线性逐步回归（MLSR）方法训练和测试了荷载与位移之间的关系。然后，确定了水位、温度和时间对位移的贡献，并解释了水位和温度对位移的影响特征。最后，通过建立大坝有限元模型并模拟各种运行条件下的应力分布，评估了大坝的应力状态。结果表明：（1）最后一次加固后，大坝目前处于弹性状态；（2）温度对位移的贡献最大，温度的剧烈波动是多拱坝安全的不利因素；（3）应力通常能满足规范要求；（4）研究的思路和方法可为其他混凝土坝的安全评估提供参考。
