Comparative evaluation of mitigation methods for traffic-induced reflective cracking in airport composite pavement

Abstract

Composite pavement provides an effective and quick solution to restore structural and functional capacity of airfield pavement. However, discontinuities of concrete slabs cause initiation and propagation of reflective cracking in asphalt overlay. This study aims to evaluate and compare the effectiveness of mitigation methods for traffic-induced reflective cracking in airport composite pavements. Finite element (FE) models were developed and validated to predict pavement responses under heavy weight deflectometer (HWD) and aircraft tire loading. The load transfer efficiency (LTE) of existing rigid pavement were evaluated under common deterioration scenarios like base erosion and concrete damage. The crack potential was indicated by pseudo J-integral considering stress intensity factors (SIFs) of different fracture modes. The results show that thicker asphalt overlay, stress absorbing interlayer, and increase of LTE can help mitigate reflective cracking. Increasing 51-mm overlay (from 76 mm to 127 mm) and applying 25-mm interlayer show the similar reduction in reflective cracking fracture potential by about 35% at early crack stage. However, applying interlayer has more benefit on cost effectiveness and pavement elevation control. On the other hand, dowel bar retrofit and base treatment can improve LTE and thus reduce the crack potential at early crack stage of 76-mm overlay by 40% on doweled pavement and 60% on un-doweled pavement, respectively.