Embankment Construction on Power Blender Cement Mixed Soft Soil Treated Ground for CKE Bypass

Power Blender cement mix soft soil improvement method was adopted for the construction of embankment of the 4-lane bypass of Colombo-Katunayake Expressway for the New Bridge Construction over the Kelani River in Sri Lanka. This treatment method is a rapid construction method, first applied in Sri Lanka. The embankment height varies from 2 m to 5 m and peat/organic clay exists for a depth of about 10 m. Soil cement columns are spaced at 1 m × 2 m rectangular shape and the improvement depth is about 10 m. After completion of the ground treatment for the entire area and confirming the quality of the improvement, the embankment was constructed with 2 layers of geotextiles. During the embankment construction, settlement and lateral movement were measured. The expected settlements and lateral deformations were estimated and compared with field measurements. This paper describes the geological condition, embankment construction sequence, settlement estimate and stability analysis, measurement results and the comparison with the respective estimates.