Cracking resistance of thin-bonded overlays using fracture test, numerical simulations and early field performance

Thin-bonded bituminous overlays are becoming an increasingly popular pavement maintenance treatment, which can be used to restore smoothness, seal and renew the pavement surface and increase skid resistance. Thin-bonded overlays (TBOs) are constructed using a specialised type of paving equipment called a ‘spray paver’. A spray paver combines the operation of applying a tack coat and laying down asphalt concrete in a single pass. This allows for the application of a high rate of polymer-modified asphalt emulsion tack coat. Due to reduced thickness, cracking distress is more of a concern in this type of system. This paper describes a new approach for the evaluation of the cracking performance of TBO systems through fracture mechanics-based testing of laboratory and field specimens. Computer simulations and early field performance data are also used in the evaluation. This study is conducted in the context of three field projects which encompass seven different pavement test sections. The test sections allowed a number of variables to be studied, including type and application rate of tack coat emulsion and type of hot-mix asphalt gradation structure (gap graded vs. dense graded). Comparisons are also made between overlays constructed using spray paver and conventional paving process. All seven sections were computationally simulated to evaluate their performance in the context of thermal and reflective cracking potential. Fairly good agreement is observed between laboratory tests, computer simulations and field performance data. The results indicate that good thermal and reflective cracking resistance are expected from TBOs. Furthermore, it was observed that the cracking performance of TBOs depends on the type of gradation for the overlay mixture and the tack coat emulsion type and its application rate.

[1]  Judith B. Corley-Lay,et al.  Ultrathin Bonded Wearing Course as Pavement Preservation Treatment for Jointed Concrete Pavements , 2007 .

[2]  Joseph F Labuz,et al.  Observation of Crack Propagation in Asphalt Mixtures with Acoustic Emission , 2006 .

[3]  Imad L. Al-Qadi,et al.  Finite Element Method Modeling of Reflective Cracking Initiation and Propagation: Investigation of the Effect of Steel Reinforcement Interlayer on Retarding Reflective Cracking in Hot-Mix Asphalt Overlay , 2006 .

[4]  William G. Buttlar,et al.  Low Temperature Cracking Prediction with Consideration of Temperature Dependent Bulk and Fracture Properties , 2010 .

[5]  James S. Moulthrop,et al.  Selecting a Preventive Maintenance Treatment for Flexible Pavements , 1999 .

[6]  Barry J. Dempsey,et al.  Enhanced Integrated Climatic Model Version 2.0 , 1997 .

[7]  Glaucio H. Paulino,et al.  A bilinear cohesive zone model tailored for fracture of asphalt concrete considering viscoelastic bulk material , 2006 .

[8]  W. Buttlar,et al.  Thermal reflective cracking of asphalt concrete overlays , 2010 .

[9]  P. J.,et al.  NEW TYPE OF ULTRATHIN FRICTION COURSE , 1991 .

[10]  W. Buttlar,et al.  Compact tension test for fracture characterization of thin bonded asphalt overlay systems at low temperature , 2012 .

[11]  E V Dave Integration of laboratory testing, field performance and numerical simulations for the study of low-temperature cracking , 2008 .

[12]  Jorge Barbosa Soares,et al.  Model for Predicting Damage Evolution in Heterogeneous Viscoelastic Asphaltic Mixtures , 2004 .

[13]  Y Brosseaud,et al.  THINNER AND THINNER ASPHALT LAYERS FOR MAINTENANCE OF FRENCH ROADS , 1992 .

[14]  Sarfraz Ahmed,et al.  Fracture characterization of thin bonded asphalt concrete overlay systems , 2011 .

[15]  Douglas I Hanson Construction and Performance of an Ultrathin Bonded Hot-Mix Asphalt Wearing Course , 2001 .

[16]  I. Al-Qadi,et al.  A fracture-based constitutive model for pavement interface characterization , 2008 .

[17]  G. H. Paulino,et al.  Disk-shaped compact tension test for asphalt concrete fracture , 2005 .

[18]  Prithvi S. Kandhal,et al.  CONSTRUCTION AND PERFORMANCE OF ULTRATHIN ASPHALT FRICTION COURSE , 1997 .

[19]  G. H. Paulino,et al.  Reflective and thermal cracking modeling of asphalt concrete overlays , 2007 .

[20]  Cindy K Estakhri,et al.  EVALUATION OF ULTRATHIN FRICTION COURSE , 1994 .

[21]  Jerry Geib,et al.  Performance of Ultra-Thin Bounded Wearing Course (UTBWC) Surface Treatment on US-169 Princeton, MN , 2007 .