A $9-$inch concrete slab is placed on a $8-$inch subbase course. There is a rigid foundation

$8-$feet below the subgrade. The monthly resilient modulus values for the subgrade and

subbase from January through December are as follows:

There is also a potential for loss of support due to subbase erosion. Check the

adequacy of the design using the following given parameters: ESAL$=6$ million; concrete

compressive strength $=6000$; concrete modulus of rupture $=700$; drainage is

excellent, but the area has heavy rainfall; load transfer coefficient, $J=3\mathrm{.}5.$