Numerical analysis of rehabilitated concrete pavement using crack-and-seating technique

Abstract

ABSTRACT Crack-and-seating is a Portland cement concrete (PCC) pavement rehabilitation technique that has been practically used to mitigate reflective cracking, however, the mechanism is not well understood. This study applied the coupling discrete-continuum modelling method to a field project, which is aimed to evaluating the effect of hammer-introduced crack on the stress at the tip of joint and at the tip of crack that control the reflective cracking of a rehabilitated PCC pavement with asphalt concrete (AC) layer. Particle Flow Code (PFC) was used for modelling asphalt overlay and the fractured PCC pavement while Fast Lagrangian Analysis of Continuum (FLAC) was used for modelling base and subgrade soil. The numerical simulation and analysis has validated that crack-and-seating can effectively reduce the shear stress at the tip of joint. Reducing the distance from the location where the hammer-introduced crack is introduced to the joint can effectively reduce the shear stress, and such distance is recommended to be 0.1–0.2 m. When the hammer-introduced crack’s length is 0.225 m, that is, the tip of crack is 1/10 of the thickness of PCC slab distant from the PCC slab surface, reflective cracking that would ultimately occur in the AC overlay can be effectively mitigated.