Damage to cemented materials

A damage function similar to the one used for fatigue damage of asphalt materials may be used for other cemented materials. It may be based on either the maximum tensile strain or stress at the bottom of the layer. The modulus of the layer is reduced by multiplying the intact modulus by (1 - w), where w is the damage.

where MN is the number of load repetitions in millions,

 resp is the response (horizontal tensile stress or strain at the bottom of the layer),

 respref is a reference response (can be related to strength),

 E is the modulus of the material (adjusted for climate and damage),

 Eref is a reference modulus, and

 A, a, b and g are constants.