Abstract: This paper presents a case history of the ground improvement monitoring results in the mountain area of Guangdong Province. The expressway embankment over the soft soils was improved by the pipe piles. When the embankment height was only 4.97 meters, the observed maximum vertical settlement was 443 millimeters and the maximum lateral deflection was 168 millimeters. Additional geotechnical investigations by the cone penetrometer testing were performed and the stability of the embankment was reevaluated. The ultimate vertical settlement and lateral movement were predicted. The results indicate that, the ultimate vertical and lateral deformations are within the controllable range. From the monitored data, the embankment deformation rate have the characterization of rapid in the initial stage and would gradually reduce the rate.

Key words: Soft Soils in Mountain Areas, Pipe pile Treated Soft Soils, Stability Analysis