As instrumentation and computing technologies have advanced, it has become possible to measure stresses, pressures, deflections, moisture, temperature, and wheel wander in pavements using embedded instrumentation instead of utilizing computer programs to estimate them (7). When actual measurements from pavement structures are used in transfer functions, the results are threefold.
First, the design life of the pavement structure will be more accurately quantified. Second, the transfer functions used to estimate design life can be calibrated and validated using actual field data to improve the design procedure. Last, and perhaps most importantly, field measurements can aid in the refinement and development of theoretical models.