Accounting of Damage of Asphalt Concrete in the Criteria for Calculating the Pavement

The aim of the article is to develop a general method for accounting for the accumulation of damage in asphalt concrete when calculating pavement according to strength criteria. The article analyzes the methods of calculating pavement according to the criteria: elastic deflection, resistance of the asphalt concrete to tensile bending, and shear resistance in the soil of subgrade. It is established that at present the fatigue of materials is taken into account by mathematical functions that connect the strength parameters of asphalt concrete with the number of applied loads. However, there is no single solution that take into account the effect of damage of asphalt concrete in the pavement on stresses and deformations that occur in the pavement and other layers of pavement. It is proposed to use the principle of equivalent deformation of a damaged and undamaged body to calculate the damage of asphalt concrete. In accordance with the formula of this principle, the elastic modulus decreases with increasing damage. The resulting formula allows to calculate the modulus of elasticity of the upper layer of a two-layer system when calculating pavement according to the criteria of coating resistance to tensile from bending and shear in the soil of subgrade. The same formula allows us to calculate the equivalent elastic modulus of a two-layer system. Thus, the proposed calculation method contains one general approach to accounting for damage accumulation in all three criteria for calculating pavement on strength.