Influence of construction factors on pullout resistance of strip from cement-treated soil in reinforced earth wall

摘要

In the reinforced earth wall method, sandy soil, which exhibits highly frictional resistance, is generally applied as the backfill material. Recently, however, there have been cases where soil at a site containing lots of fine fraction was applied as the backfill material after conducting cement stabilization. In the process of construction using cement stabilization, the pullout resistance characteristics of the strip are influenced by various factors, including the time span from the cement stabilization at the plant to the compaction of the backfill material, the times of the surface compaction of the cement-stabilized backfill material, the strength difference between the upper and lower layers of the strip caused by the construction interruption, and the leaving time between the last loading and next loading in the phased construction. We attempted to clarify the influence of these factors by performing pullout tests in the laboratory. The results indicated that the pullout resistance of the strip in the cemented soil layer was affected by the time span from mixing to the filling, while the strength difference between the upper and lower layers of the strip and the leaving time until the next loading of vertical stress hardly influenced the resistance.