Reflection Cracking Parameters

The following controls, located on the Input -> Simulation Parameters Page, are used to specify the reflection cracking parameters associated with the Mechanistic-Empirical simulation.

The reflection of cracks through overlying layers maybe included in the simulation by selecting the radio buttons shown below. The default is None. These radio buttons will be enabled if the structure has certain layer material types: HMA (or RHMA) over HMA and HMA over PCC or CTB, otherwise they will be disabled.

Reflection Cracking Controls:

•None - this is the default selection

•AC on AC - There needs to be multiple layers of HMA (AC) or RHMA over HMA for this control to be enabled.

•AC on Cemented Base - this radio button becomes enabled if there is HMA over a cemented base

•Existing Cracking - specifies the amount of existing wheel path cracking (longitudinal and transverse), in percent. This control becomes enabled when the Reflection Cracking is set to "AC on AC". The are five ranges of Existing Cracking:

•0 - 5

•6 -  15

•16 - 25

•26 - 35

•>35

•Cracked layers(s) from - If the cracking is not reflecting from layer number 2 through an overlay, but from a deeper layer, the number of this layer must be entered in "Cracked layer" (if Cracked layer is 0 CalME assumes that cracks reflect from layer number 2).

•Find Them - this button assists in locating the layers for cracking

The question mark in the blue circle in the upper-right of the control group allows you to get help on the controls (this topic).