using Fig. 3.12 and entered in column 5. The corrected k value is then used in Fig. 3.13
to determine the seasonal or relative damage factor, which is entered in column 6. The sum
of relative damage is divided by the total number of periods to determine the average relative
damage factor. This value is entered in Fig. 3.13 to determine the average composite
modulus of subgrade reaction for the year. Many concrete pavements fail as a result of
pumping or loss of support under the slab. Figure 3.14 is provided to correct the effective
modulus of subgrade reaction for loss of support. This figure lowers the k so that the