Reconstruction of a Cement-Stabilized Fly Ash Sub-base

摘要

A 20-year-old cement-stabilized fly ash (CSFA) subbase that had badly disintegrated was rebound by addition of portland cement. Asphalt granulate from the road and sand from the bed below the road were mixed with the old CSFA to improve the grain size distribution. Laboratory tests were performed to determine the required cement content, with the intention to take both civil engineering and environmental properties into account. For this purpose, test specimens with varying cement content were produced that were used for determination of the compressive strength as well as leaching rates. After successfully finishing the laboratory research, the actual reconstruction was performed in a demonstration project.