You wouldn't want to create range from an earlier range (L5-L7), that doesn't make sense. However, in addition to L1-L3, you may also need L1-L2 and L2-L3. The necessity of these cases depends on what load magnitudes actually make up L1, L2, and L3. The objective is to encompass the extreme displacement stress range.
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Regards,
Richard Ay - Consultant