Analytic pavement modelling with a fragmented layer

Layered elastic theory is a familiar and commonly accepted framework for modelling and analysis of pavement systems. In actuality however, the suitability of the theory is challenged whenever the system includes a fragmented layer – which violates the inherent layer continuity assumption. This paper addressed the modelling challenge in these situations by introducing a fragmented layer into the accepted framework. A new formulation was proposed, based on the hypothesis that the thickness of the fragmented layer can be incorporated as part of its governing parameters. Doing so allowed for treating the fragmented layer as a new kind of interface. Subsequently, the work focused on formulation development and clear step-by-step presentation of new derived expressions applicable to the case of a stratified half-space containing a fragmented layer. Several synthetic cases were generated and interrogated to verify the correctness of underlying equations and to demonstrate capabilities. Based on this interrogation the proposed formulation is deemed rich of prospective utility, especially for modelling pavements surfaced with concrete paving blocks, pavement systems that contain cracked-and-seated (or rubblised) Portland cement concrete, and aged or rehabilitated pavement systems that contain fatigued (multi-fractured) asphalt concrete layers.