Theoretical analysis of overlay resisting crack propagation in old cement concrete pavement

The main purpose of this study is to determine the effect of overlay on the crack propagation. To simplify the problem, a cement concrete pavement is modelled as an elastic plate on Winkler foundation. To drive the singular integral equations, the Fourier transform and dislocation density function are used. Lobatto–Chebyshev integration formula, as a numerical method, is used to solve the singular integral equations. The numerical solution of the stress intensity factor at the crack tip is derived. To examine the effect of overlay for resisting the crack propagation, numerical analyses are carried out on a cement concrete pavement with embedded crack and a concrete pavement with an asphalt overlay. Results show that the thickness and the shear modulus are two significant factors influencing the crack propagation.