Abstract: To solve problems caused by large-scale deep soft soil foundation of Chaoshan Airport, the preloading method which takes plastic drainage board and sand drain as vertical drainage channels was systemically studied and was applied to the project. The preloading scheme was selected based on analysis of geological conditions of the construction site, and then the details of sand cushion laying, plastic drainage board and sand drain construction, problems and their solutions during construction were discussed. Finally the result of soil foundation treatment was verified by monitoring data. The results show that the method taken in this project is reliable, effective and suitable for the treatment of deep soft soil foundation.

Key words: soft soil foundation, drainage and consolidation, preloading method, foundation treatment, settlement