Evaluating the Effect of Base Course Material Modification on Pavement Performance

Authors

Mohamed Ragab

Abstract

In pavement construction, the mechanical properties of pavement layers have been a crucial concern. Additions such as lime, organic polymer, and sodium chloride have been used as modifier for enhancing the California Bearing Ratio (CBR) value of the natural dolomite soil. This paper proposed regression models relating the CBR values and percentages increase of CBR to dosages of the used additives. Furthermore, the paper tested the performance of the Generalized Concentration Addition (GCA) analytical modelling of CBR enhancement related to using different mixes of additives. Lime-organic polymers mix has utilized to upgrade the CBR. Percentages of enhancement were measured and employed to assess the GCA model results. Results indicated that the highest CBR value of 136% was noticed at 30% of organic polymer. On the other hand, the lowest value of CBR value of 50.2% was noticed at 3% of lime. Furthermore, percentages of 9% lime, 5% sodium chloride, and 10% organic polymer were recommended to improve the CBR value of the base layer. Regression models showed high representativeness owing factors of correlation of determination (R2) higher than 90%. Moreover, GCA results showed good fit to laboratory measured percentage increase of CBR as R2 higher than 80% is gained with acceptable values of Root Mean Square Error (RMSE), Frictional Biases (FB) and Global Mean Biases (MB). Finally, percentages of 9% lime, 5% sodium chloride, and 10% organic polymer saved about 43.6%, 28.5% and 50% of the base layer thickness for the same materials respectively.

Recommended Citation

Ragab, Mohamed (2023) "Evaluating the Effect of Base Course Material Modification on Pavement Performance," Journal of Engineering Research: Vol. 7: Iss. 1, Article 3.
Available at: https://digitalcommons.aaru.edu.jo/erjeng/vol7/iss1/3