Sub SolveForSN() Range("A22").GoalSeek Goal:=0, ChangingCell:=Range("A20") MsgBox "Required SN = " & Round(Range("A20").Value, 3) End Sub
| Feature | Benefit | |---------|---------| | | Prevents incorrect m-values | | Seasonal MR adjustment | Computes effective MR from monthly MR values | | Solver add-in automation | One-click SN calculation without circular refs | | Layer thickness rounding | Rounds to nearest 0.5 inch (practical construction) | | Minimum thickness check | Warns if D1 < 2″ (HMA) or D2 < 4″ (base) | | Chart: SN vs. ESALs | Visual sensitivity for design life | | Comparison with 1986/2002 guides | Side-by-side tabs for method validation | aashto flexible pavement design excel spreadsheet