Abstract：Current situation of construction stabilizing fluid for underground diaphragm wall is analyzed. Characteristic property of polymer solution is fully discussed. Optimum seeking method is used to study a new kind of construction stabilizing fluid for underground diaphragm wall-polymer solution. This solution is compared with slurry solution and displays its superiority-can meet the requirements of extremely loose floating sand layers，soft soil layers，and construction sections where slurry can¢t resist collapse，or collapsed construction section. Finally，the mechanism of protecting hole wall of polymer solution is discussed. It provides academic basis for the development of this new kind of construction stabilizing fluid for underground diaphragm wall.
