Solar Farm Foundations

Dr. Richard Kelly

The solar industry has boomed over the past few years and will continue to grow at a rapid pace into the future. Typically solar farms are placed where there is sun, where there is space and relatively near to existing transmission lines. Typically solar farms are supported on posts driven a relatively short distance into the ground in order to resist lateral and vertical wind loads and accommodate ground movements. This near surface construction requires geotechnical engineers to consider different issues than historically has been required in foundation design. In particular, effects of wetting and drying on the strength, stiffness and structure of the soil need to be considered. Some questions are: to what extent should unsaturated behaviour be considered? Does dessication and cracking matter? Do cycles of shrinking and swelling continually jack piles out of the ground? What happens when it floods? Do floods and high winds occur concurrently? What is an appropriate probability of movement exceeding design criteria? How to quantify corrosion rates of galvanised steel? What is an appropriate probability of structural failure? Many of these questions are unresolved and require an engineer to use judgement based on science, testing and experience. Some thoughts on these issues will be discussed.

About the speaker

Dr. Richard Kelly Chief Technical Principal for Geotechnical Engineering & General Manager for Technical Excellence, SMEC

Dr Richard Kelly is Chief Technical Principal for Geotechnical Engineering and General Manager for Technical Excellence at SMEC. He has over 25 years experience, mainly in infrastructure and has worked in academia for 9 years. Richard is involved in a large number of renewable energy projects including many solar farms across Australia.

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