The design of pile foundations for photovoltaic power stations in cold, high-altitude pastoral regions lacks standardized guidelines. Investigating the optimization of uplift performance is therefore essential for ensuring engineering quality and promoting sustainable construction. In this study, the Kela photovoltaic power station was taken as the engineering background, and a combined approach of full-scale field uplift tests and numerical simulations was adopted. The effects of pile type, backfilling method, web plate configuration, and predrilled hole diameter on the uplift bearing capacity of pile foundations were systematically investigated. The results indicate that the uplift bearing capacity of H-section steel piles is significantly higher than that of steel pipe piles. The use of cement-improved backfill further enhances the bearing performance. As the cement mortar content increases from 0% to 90%, the uplift capacity of a single pile increases from 21.258 kN to 23.762 kN. Installing a single web plate at 0.3 m above the pile tip yields the optimal configuration, increasing the uplift capacity from 19.557 kN to 22.448 kN, while additional web plates exhibit a clear diminishing marginal effect. As the predrilled hole diameter increases from φ152 mm to φ164 mm, the uplift capacity increases from 18.025 kN to 21.784 kN, although the rate of increase gradually decreases. After optimizing the web plate configuration and hole diameter, the required minimum embedment depth ranges from 1.45 m to 2.03 m under different ground conditions, and increases progressively with deteriorating foundation conditions. This study fills the gap in the optimal design of photovoltaic pile foundations in cold, high-altitude pastoral regions, and provides theoretical guidance and design parameters for engineering applications in western Sichuan and similar regions.
Wu et al. (Wed,) studied this question.