## 1 Introduction  
With the development of clean energy globally, the new site selection of water conservancy, hydropower, and pumped storage projects faces more complex terrain and geological conditions. At the same time, existing projects are aging and constantly challenge the limit of traditional dam design experience and material safety [1]. Therefore, it is of great significance to accurately and efficiently excavate the hidden information of the uplift pressure monitoring data [2] and clarify the safety state of the concrete dam to reduce the hidden dangers of reservoir dam engineering [3]. In 1959, the Malpasset arch dam in France suffered dam failure due to the sliding of the dam shoulder under the high water level, resulting in 421 deaths and property losses of 30 billion francs. Due to this, many researchers and engineers should attach great importance to the uplift pressure of concrete dams [4]. As an essential load of concrete dams, uplift pressure significantly influences the stress, deformation, and stability of the concrete dam [5]. In the process of concrete dam design, uplift pressure statistical analysis is usually carried out according to the existing dams, and the value and distribution of uplift pressure are determined in combination with design experience [6]. However, due to the complex distribution of cracks in the dam foundation and the concealment of seepage control measures, the real value and distribution of the uplift pressure of the concrete dam are affected by many factors, which are relatively different from the design. [PERSON] et al. [7] studied the influence mechanism of uplift pressure on a concrete gravity dam by model test, and they think the uplift pressures must be considered in the original design. Especially for the concrete gravity dam with crack, the influence of uplift pressure on the stress intensity factor and crack propagation angle was significant through the research by [PERSON] [8]. [PERSON] et al. [9], [PERSON] et al. [10], and [PERSON] et al. [11] analyzed the variation of uplift pressure under an earthquake, which is very unfavorable to the stability of the cracked dam. [PERSON] et al. [12] and [PERSON] et al. [13] proved uplift pressure plays a vital role in the stability analysis of dam abutment by the finite element method (FEM). Furthermore, [PERSON] et al. [14] used the fluid-solid coupling method to analyze the safety and stability of a gravity dam under uplift pressure. [PERSON] et al. [15] discussed different uplift pressure simulation methods, and the equivalent uplift pressure simulation method is feasible under complex situations. [PERSON] et al. [16] research the reason for the abnormal uplift pressure of the Huaguangtan dam using the orehole video tests and numerical simulation. As described in [17], the influence of uplift pressure on dam stress can exceed 30%, and the influence scope can exceed 20%. Excessive uplift pressure leads to instability of underground structures [18]. Thus, practical uplift pressure should be applied when analyzing concrete structures. On the other hand, some scholars have studied the anomaly identification of uplift pressure during the operation period of concrete dams, and the applicability of various anomaly identification methods is compared [19]. The membership cloud method was proposed for identifying abnormal data by [PERSON] et al. [20], and the uplift pressure monitoring data of the Gongzui gravity dam is identified. [PERSON] et al. [21] constructed a time series anomaly identification method, combining dynamic time distortion and local outlier factors, to find out the local uplift of the Xixi dam foundation. Then, [PERSON] et al. [22] integrated statistical analyses, inversion analyses, and field investigations to explain the causes of sudden increases of uplift pressures. A hybrid prediction model and supervised learning method, for outlier identification of dam monitoring data, were built by [PERSON] [23].