Abbas Al-Hdabi - PhD Graduate from Liverpool John Moores University, Liverpool, UK
Mohammed K. Fakhraldin - Lecturer, Department of Civil Engineering, Faculty of Engineering, University of Kufa, Al-Najaf, Iraq
Rasha A. Al-Fatlawy - Assistance Lecturer, Department of Civil Engineering, Faculty of Engineering, University of Kufa, Al-Najaf, Iraq,

industrial by product materials which are generated from cement manufacturing must be managed responsibly, such as the other industries, to insure a clean and safe environment. Cement Kiln Dust (CKD) is a significant by product material of the cement manufacturing process. The majority of CKD is recycled back into the cement kiln as a raw feed. Other beneficial applications were then adopted such as agricultural soil enhancement, base stabilization for pavements, wastewater treatment and waste remediation.This research introduces a new method to upgrade the performance of the granular materials which are normally used in subbase courses. The proposed method can be characterized by adding CKD lining within this layer. CKD lining was with 0.1H (0.1 of the total thickness of granular material samples) and posted in different locations from the top of the specimen i.e. 0.1, 0.15, 0.2, 0.25 and 0.5H. The mechanical properties, by means of California Bearing Ratio (CBR) test, has been improved significantly as it increased almost three times when 0.1H of CKD lining placed on 0.2H in comparison with untreated material. Also, this improvement can reduce the total asphalt concrete layers by almost 30% in accordance to the pavement structural analysis which is conducted in the present study.

CKD, granular materials, CBR, subbase course, soil stabilization