The focus of this research is the real-time assessment of drilled shaft capacity based
on the unconfined compressive strength (q(u)) obtained from measuring while drilling
(MWD). Measures of q(u), a function of rock strength commonly used in drilled shaft
design, are provided through five monitored drilling parameters: torque, crowd, rotational
speed, penetration rate, and bit diameter. Monitored shaft installations took place
at three separate locations on drilled shafts, which were subsequently load tested.
Using the q(u) values obtained from MWD, side shear was estimated in portions of each
shaft where instrumented segments indicated the side shear was fully mobilized for
direct comparison. To consider all of the current side shear equations used in Florida
drilled shaft design, the estimation of tensile strength (q(t)) in real time was also
needed. This led to a theoretical approach to establish the q(t)/q(u) relationship
that was later verified empirically and provided new correlations between material
and mechanical properties of Florida geomaterials. A comparative analysis indicated
that the results from multiple established side shear equations, used with q(u) from
MWD, align well with the results obtained from load testing. This suggests that estimating
drilled shaft capacity from MWD is viable to reduce spatial uncertainty.