TABLE 2
THE ASSHTO FLEXIBLE EQUATION IS AS FOLLOWS:
 
   (-0.089)   
Log (10220 x trucks/day) = 9.36 Log (SN+1) – 0.20 +
0.40 + 1094   
+0.372 (S.S.V. - 3.0)
(SN +1) 5.19
VARIABLES:
Assumed:   20-year life, 1.4-18 kips per truck
S.S.V. =   Soil Support Value
      3.4 for most Strongsville’s subsoils
      S. S. V. may be increased upon soil testing results
      S. S. V. shall be decreased for poor support soils such as clays, topsoil, shale, some silty clays, etc.
SN =   Structural Number
O.D.O.T.   Item    404   SN = .035 x thickness (inches)
   402   SN = 0.35 x thickness (inches)
   301   SN = .035 x thickness (inches)
   304   SN = 0.14 x thickness (inches)
   310   SN = 0.11 x thickness (inches)