Effect of cross anisotropy of pavement materials on flexible pavement response subjected to various subgrade modulus

Generally, layered elastic theory (LET) based pavement models considers the pavement layers to be linear elastic, homogenous and isotropic. But in reality, pavement materials exhibit cross-anisotropic behavior. Hence a study was undertaken to investigate the effect of anisotropy of pavement materials on fatigue strain and rutting strain which governs the fatigue and rutting life respectively. From the study it was observed that rutting is very sensitive to California Bearing Ratio value of subgrade. Hence, enhancement of subgrade CBR either by using lightly stabilized soil or good quality compacted granular materials should be used instead of higher thickness of base and subbase layer. Fatigue life has no sensitivity with the variation of subgrade CBR or subgrade modulus. The effect of degree of cross anisotropy (DOA) is not significant on fatigue life.