Abstract:In this paper, as the platform of geotechnical engineering projects, structure, application principles, characteristics, applicable scope as well as the regarding problems of petrol tank raft during the process of building and construction have been introduced. Through contrast between two drilling examples, it is regarded that good economic and social benefits can be gained through petrol tank raft. It can test the feasibility, security, flexibility and effectiveness through the theory. It is worth to be popularized for the simple water drilling projects because of its strong operability and good practicability.