So far, I have only been able to model dry layers as I've only been able to represent the FDR layer with one modulus value.
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Please refer to the Manual of Practice for the Mechanistic-Empirical Pavement Design Guide (MEPDG). The following is an extract from that manual:
Full-Depth Reclamation (In-Place Pulverization of Conventional Flexible Pavements) - Cold in-place recycling of the HMA and existing aggregate base layers, and hot in-place recycling of HMA. Cold in-place recycling as a rehabilitation strategy is considered reconstruction under the MEPDG design/analysis process and would be defined as a new flexible pavement. Hot in place recycling as a rehabilitation strategy is considered mill and fill with an HMA overlay of the existing flexible pavement. The thickness of the hot in-place recycled material is considered part of the HMA overlay, as well as the thickness of the milled material. Full-depth reclamation, however, was not included in the global calibration of AASHTOWare Pavement ME Design.
Mechanistic-Empirical Pavement Design Guide - A Manual of Practice 2015 (AASHTO)
How you treat or simulate the FDR layer is an engineering decision. It depends on how the FDR layer is stabilized and designed.
If you are adding an emulsion to the reclaimed layer, it can be simulated as a conventional asphalt layer and the pavement can then be simulated as new construction. If an emulsion is used and the layer is simulated as an asphalt layer for new construction, you need to determine whether the default or local calibration coefficients for fatigue cracking apply to this FDR layer.
This decision will depend on how that FDR layer with emulsion added is designed and constructed. Some State agencies model the FDR layer as a high strength granular layer with a representative resilient modulus when a low amount of asphalt binder (4 percent or less) is used as the stabilizing material (Virginia for example).