Based on the meteorological and hydrographic and groundwater conditions at the area around Hefei,the paper analyzes the hydraulic connection and running rules of groundwater and surface water at the area;and combining with the current hydrographic data,it also makes analysis of anti-uplift water level during the design of basement and underground structure.

The ground subsidence and water level for prevention of up-floating of Beijing Shahe Higher Education Park is elaborated.

In order to insure the safe of the building,the safe groundwater level height,referred as water level for prevention of up-floating in general,must be confirmed before the design stage.

According to Specification for Geotechnical Investigation of Tall Buidings(JGJ 72—2004),the water level for prevention of up-floating should adopt the highest water level determined during investigation construction.

In-depth analysis about various anti-floating design projects commonly used in concrete water pool design was carried out,and measures against various antifloating in its application conditions and the economy,feasibility were proposed.

This paper analyzes the necessity of theoretical research into building anti-floating design,calculates the buoyancy,illustrates anti-floating measures at construction stages and permanent anti-floating measures,and proposes treatment measures for the building after its floating,in order to help technicians select appropriate and effective treatment methods.

Based on practical projects,the anti-floating design methods of pile foundation and raft of beam are proposed and then the design details,calculation methods and structure formations of prestressed concrete pipe pile are also introduced,effectively solve the problems existed in construction.