For a single pile, they observed the variation of subgrade modulus with respect to depth and the effect of cyclic loading on deflection.
The ultimate lateral soil resistance and subgrade modulus were investigated and discussed.
If mat footings are recommended, evaluation of soil capacities, including subgrade modulus
and an opinion to the anticipated settlement.
backcalculation equations: regression equations have been developed to predict subgrade modulus
using the deflection testing data (Newcomb 1987).
Also, in the wet season, subgrade modulus will be lower.
Back calculation process on the uncorrected FWD deflection bowl data is mainly intended to estimate subgrade modulus as is (not corrected), since this value is not significantly influenced by the survey load.
Back calculation process on the corrected FWD deflection bowl data is performed by maintaining the subgrade modulus the same.
bar] = horizontal subgrade modulus
of soil given in force/(length)3
Soil spring coefficients are calculated using a soil subgrade modulus
of 250 kip/sf/foot of deflection and projecting element areas in both the x and y directions.