Field load testing and numerical analysis of offshore photovoltaic steel pipe piles

Abstract

Photovoltaic power generation, as an emerging method of energy utilization, has demonstrated unique advantages in resource development. Offshore photovoltaic systems, characterized by their high-power generation capacity, low land occupation, and ease of integration with other industries, have become a highly regarded energy choice. These systems frequently make use of fixed pile foundations, and the crucial aspect of their design lies in the horizontal bearing capacity of these foundations. This study investigates the horizontal load-bearing properties of steel pipe piles used in offshore photovoltaic systems by conducting field tests with single-pile horizontal static loads and performing numerical analysis. The analysis findings indicate a notable increase in the horizontal movement of the pile structure as the load is progressively augmented. The site is topped with a heavy deposit of muddy soil. During the unloading stage, the rebound deformation is incomplete, resulting in significant residual deformation of the pile body after unloading. The simulation results from the numerical analysis closely match the measured values, confirming the accuracy of the mode. Furthermore, the impact of factors such as pile diameter and rock penetration depth on the horizontal bearing capacity of the test piles is analyzed. Under the same horizontal load, increasing the pile diameter and rock penetration depth can effectively reduce the displacement of the single-pile foundation. However, when the rock penetration depth exceeds four times the pile diameter, the resistance of the deep rock mass cannot be fully utilized, and the increase in the horizontal bearing capacity of the pile body slows down. The study's conclusions furnish a comprehensive reference point for evaluating the horizontal load-bearing capabilities of offshore photovoltaic pile foundations, enabling further advancements in design strategies and optimization.