Quantifying resilience in design reviews

When you can’t full-scale test, how do you convincingly demonstrate material resilience and structural safety in a review? I’m revising a bolted shear connection that passes FEA but shows low Charpy V-notch at -20 C on the specified plate; I’m leaning on fracture mechanics parameters and a targeted UT schedule, but I’d like to hear what’s worked for you without adding 15–20% mass.

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