Soil Sampling Techniques for Foundations

I’ve been refining my soil sampling techniques for foundation analysis, particularly how different methods affect the results. Recently, I used disturbed and undisturbed sampling on a project in sandy soil, and the discrepancies were quite surprising. How have others approached this, and what tools have you found most reliable?

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It’s funny how soil sampling can feel like a dating app — sometimes you think you’ve found ‘the one,’ only to discover it’s just a bad match when you dig deeper. I usually stick to a combination of split spoon and thin-walled tube sampling for reliable results, especially with sandy soils. Have you tried using a cone penetrometer?

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I’ve had similar surprises with disturbed samples in sandy soil! What’s your go-to tool for undisturbed sampling? Maybe the Shelby tube? :thinking:.

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