Evaluation of Strength Performance of Cement Treated Graded Crushed Stones (GCS) for High Traffic Volume Roads Construction in Kenya

Albert Owuor Ndege; Simpson Nyambane Osano; John Francis Gichaga

Albert Owuor Ndege, Mr. University of Nairobi
Simpson Nyambane Osano, Dr. University of Nairobi
John Francis Gichaga, Prof. University of Nairobi

Keywords: Graded crushed stone, cement, UCS, high traffic volume roads

Abstract

This study evaluates the strength performance of cement-treated Graded Crushed Stone (GCS) of 0/30 mm and 0/40 mm gradations, commonly used in Kenyan for construction of roads carrying over 10 million equivalent standard axles (MESA). While cement is often added to bind GCS fines, its effect on road performance had not been analyzed. This research assessed the Unconfined Compressive Strength (UCS) of GCS from three quarries, treated with 1%–5% cement and cured for 7, 14, and 28 days. Results showed that the 0/40 mm gradation outperformed 0/30 mm in UCS, with strength increasing steadily up to 4% cement content. Greatest UCS development occurred within the first 14 days of curing. A strong correlation (R² = 0.893) was found between UCS and the variables studied. The study recommends using 0/40 mm gradation, extended curing periods, and optimized cement content to meet performance requirements for roads with heavy traffic.

Author Biographies

Albert Owuor Ndege, Mr., University of Nairobi

Department of Civil and Construction Engineering, University of Nairobi

Simpson Nyambane Osano, Dr., University of Nairobi

Senior Lecturer, Chairman, Department of Civil and Construction Engineering, University of Nairobi

John Francis Gichaga, Prof., University of Nairobi

Lecturer, Department of Civil and Construction Engineering, University of Nairobi