Author(s): CO NG Lin, YU Lu, WEI Qiang
Pages: 86-89,94
Year: 2014 Issue:  4
Journal: Highway Engineering
Keyword:  Reflective crack; Waterproof and anti-acrack layer; Stress concentration; Stress in-tensity factor; Three-dimensional finite element;
Abstract: Reflective crack in asphalt pavement is mainly produced by too much stress concentra-tion,which is caused by inevitable temperature and drying shrinkage cracks in the semi-rigid base struc-ture.Besides,vehicle load,the large temperature change and water seepage can become the unfavorable factors of this kind of damage.The waterproof and anti-crack layer between semi-rigid base and flexible layer can effectively alleviate the stress concentration phenomenon and delay the generation and propaga-tion velocity of reflective crack.Finite element method is used to simulate the actual environment that eas-ily results in reflective cracks.The temperature-load coupling force is analyzed and contrasted in pave-ment with and without waterproof and anti-crack layer.It is found that the load stress,temperature stress and stress intensity factor have significantly reduced after the pavement structure improvement.The influ-ence of modulus and thickness of the waterproof and anti-crack layer is also calculated.The results showed that generally the modulus of waterproof and anti-crack layer is smaller,the effect is more obvious;increasing thickness of waterproof and anti-crack layer is very useful to prevent the gen-eration of reflective cracks;appropriate control on foundation modulus can also take effect.