Effect of the contact structure characteristics on rutting performance in asphalt mixtures using 2D imaging analysis

Abstract The contact structure of asphalt mixtures has been considered as an important micromechanical mixture property related to the rutting performance. In this study, a two-dimensional (2D) image acquisition and processing procedure was utilized to acquire the contact structure of asphalt mixtures with varying compactness, gradation types, nominal maximum aggregate sizes (NMAS) and binder types. New indices for contact structure of different asphalt mixtures were developed based on three aspects: contact distance distribution, contact length distribution and contact orientation, including average contact distance (d ave ), proportion for contact distance no more than 0.5 mm (P d⩽0.5mm ), proportion for contact distance no more than 1 mm (P d⩽1mm ), total contact length (L sum ), number of contact (No. contact), average contact length (L ave ), the average contact angle of inclination θ and the vector magnitude Δ. Flow number and strain rate from dynamic creep test were determined to be the rutting indicators for varying asphalt mixtures. A linear regression model was used to investigate the relationship between new contact indices and rutting indicators. The results indicated that the contact structure of varying mixtures could be successfully differed by the new indices proposed. New indices, such as L sum , L ave and d ave , could be ranked in a similar trend as the flow number. Furthermore, a more comprehensive index represented the contact structure of asphalt mixtures was developed to better uncover the mechanism of rutting in micromechanical perspective.

[1]  Andreas Loizos,et al.  Evaluation of the effects of gyratory and field compaction on asphalt mix internal structure , 2016 .

[2]  J. Boone,et al.  A micromechanical approach to investigate asphalt concrete rutting mechanisms , 2012 .

[3]  Jing Hu,et al.  High-temperature failure in asphalt mixtures using micro-structural investigation and image analysis , 2015 .

[4]  Susan L. Tighe,et al.  A novel method for evaluating hot mix asphalt fatigue damage: X-ray computed tomography , 2016 .

[6]  Hainian Wang,et al.  Evaluation of Coarse Aggregate in Cold Recycling Mixes Using X-Ray CT Scanner and Image Analysis , 2016 .

[7]  Han Zhu,et al.  Contact based analysis of asphalt pavement with the effect of aggregate angularity , 2000 .

[8]  Joe W Button,et al.  Implications of Experimental Measurements and Analyses of the Internal Structure of Hot-Mix Asphalt , 2004 .

[9]  Richard M. Leahy,et al.  Determination of Internal Deformation Field in Asphalt Cores Using X-Ray Computer Tomography , 1996 .

[10]  M. R. Hainin,et al.  Characterisation of micro-structural damage in asphalt mixtures using image analysis , 2014 .

[11]  Hussain U Bahia,et al.  Internal structure characterization of asphalt mixtures for rutting performance using imaging analysis , 2012 .

[12]  Hussain U. Bahia,et al.  Effect of compaction conditions on aggregate packing using 2-dimensional image analysis and the relation to performance of HMA , 2014 .

[13]  N. Otsu.  A threshold selection method from gray level histograms , 1979 .

[14]  Fujian Ni,et al.  Evaluation of microstructure and damage evolution for asphalt pavements in an advanced repeated load permanent deformation test using X-ray computed tomography , 2017 .

[15]  Hussain U Bahia,et al.  Aggregate structure characterisation of asphalt mixtures using two-dimensional image analysis , 2012 .

[17]  Andy Collop,et al.  Aggregate Orientation and Segregation in Laboratory-Compacted Asphalt Samples , 2004 .