AASHTO PP 112-21

This practice describes a method to assess the capability of a surrogate test to be used as a substitute for a standard test. The surrogate tests must demonstrate the capability to provide test results similar to the standard test method with a minimum of additional variability. The test results from the standard and the surrogate are compared and the error in their relationship is quantified.
It may be desirable to use a surrogate test to monitor material quality during construction or production, especially if the standard test method uses complex/expensive equipment, requires time-consuming sample preparation and testing techniques, uses hazardous materials, or involves destroying a portion of the material. This standard practice is intended to be applied for construction quality control but may also be used for acceptance if specifically approved by the Agency.
The procedure in this standard should be followed in the evaluation of potential surrogate test methods and to set parameters for their use.