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The Baihetan Hydropower Station reservoir area began impoundment in 2021, triggering the reactivation of ancient landslides and the formation of new ones. This not only caused direct landslide disasters but also significantly increased the likelihood of secondary surge wave disasters. This study takes the Wangjiashan (WJS) landslide in the Baihetan reservoir area as an example and conducts large-scale three-dimensional physical model experiments. Based on the results of the physical model experiments, numerical simulation is used as a comparative verification tool. The results show that the numerical simulation method effectively reproduces the formation and propagation process of the WJS landslide-induced surge waves observed in the physical experiments. At the impoundment water level of 825 m, the surge waves generated by the WJS landslide pose potential threats to the Xiangbiling (XBL) residential area. In this study, the numerical simulation based on computational fluid dynamics confirmed the actual propagation forms of the surge waves, aligning well with the results of the physical experiments at a microscopic scale. However, at a macroscopic scale, there is some discrepancy between the numerical simulation results and the physical experiment outcomes, with a maximum error of 25%, primarily stemming from the three-dimensional numerical source model. This study emphasizes the critical role of physical model experiments in understanding and mitigating surge wave disasters in China. Furthermore, physical experiments remain crucial for accurate disaster prediction and mitigation strategies. The theories and methods used in this study will provide important references for future research related to landslide disasters in reservoir areas. [ABSTRACT FROM AUTHOR]

When excavating the rock foundation of a hydropower station, it will be affected by the phenomenon of unloading and relaxation, which may increase the risk of stability of the dam foundation engineering system. The dam foundation of Baihetan Hydropower is a columnar jointed rock mass (CJRM), which presents strong brittleness and anisotropy compared to traditional dam foundation rocks. Therefore, this type of rock mass is prone to disturbance to the dam body, structure, etc. during excavation, so it is necessary to accurately evaluate the impact of dam foundation excavation. Establishing a rock mass creep models serve as an effective tool for evaluating such stability but often suffer from significant parameter uncertainty. Digital twin technology, a virtual model, is capable of real-time learning from actual monitoring data obtained from the physical entity to enhance the performance of the built-in mechanistic model. In this study, the researchers employ the classical Burgers constitutive equation as the theoretical framework and integrate it with an ensemble smoother with multiple data assimilation (ESMDA) method based on Bayesian principles, along with displacement monitoring data from the Baihetan Dam foundation, to construct a digital twin model. Within this framework, the researchers analyze the uncertainty of rheological parameters at various measurement points in the Baihetan Dam foundation. Subsequently, the most suitable rheological parameters are selected and incorporated into the constitutive model to obtain displacement estimates, which are then compared with on-site monitoring data. The results demonstrate that the proposed method effectively performs probabilistic parameter estimation and model prediction for rheological mechanics. This research integrates data-driven methods with mechanical principles, offering a reliable approach for assessing the uncertainty of unloading rheological parameters and displacement prediction in dam foundations, thereby providing essential support for the evaluation of excavation projects in the CJRM of the Baihetan Dam foundation. [ABSTRACT FROM AUTHOR]

Aim: To compare the efficacy and safety of a fixed‐ratio combination of insulin glargine 100 U/mL plus lixisenatide (iGlarLixi) with premixed insulin, insulin degludec plus insulin aspart (IDegAsp), in Chinese people with type 2 diabetes (T2D) suboptimally controlled with oral antidiabetic drug(s) (OADs). Methods: In Soli‐D, a 24‐week, multicentre, open‐label, study, insulin‐naïve adults were randomized 1:1 to once‐daily injections of iGlarLixi (n = 291) or IDegAsp (n = 291), with continued metformin ± sodium‐glucose co‐transporter‐2 inhibitors. The primary endpoint was non‐inferiority in HbA1c change from baseline to week 24. Key secondary endpoints included superiority in HbA1c change and body weight (BW) change at week 24. Hypoglycaemia rates were also assessed. Results: At week 24, iGlarLixi showed non‐inferiority and superiority over IDegAsp in HbA1c reduction (least squares [LS] mean difference: −0.20 [95% confidence interval {CI}: –0.33, −0.07]; P <.001 for non‐inferiority; [97.5% CI: –0.35, −0.05]; P =.003 for superiority). iGlarLixi decreased BW and IDegAsp increased BW from baseline to week 24, with a statistically significant LS mean difference of −1.49 kg in favour of iGlarLixi (97.5% CI: –2.32, −0.66; P <.001). Event rates (per person‐year) for American Diabetes Association (ADA) Level 1, 2 or 3 hypoglycaemia were lower for iGlarLixi (1.90) versus IDegAsp (2.72) (relative risk: 0.71; 95% CI: 0.52, 0.98). No ADA Level 3 hypoglycaemia or unexpected safety findings were reported. Conclusions: In Chinese people with T2D suboptimally controlled with OADs, once‐daily iGlarLixi provided better glycaemic control with BW benefit and lower hypoglycaemia event rates versus IDegAsp. [ABSTRACT FROM AUTHOR]