METHOD OF REMOVING NEGATIVE FRICTIONAL FORCE FOR CAST-IN-PLACE PILE

摘要

PURPOSE:To simply place concrete and securely remove a frictional force, by applying direct current so as for the electric conductive member side to become anode between the electric conductive member attached to the external peripheral of an excavated hole filled with mud water and the steel frame. CONSTITUTION:A circular steel net 16 of an electric conductive member is arranged at the external periphery of an excavated hole 10 formed with suspended mud water 12 of bentonite or the like and a steel frame cage 14 is installed so that the steel frame of the external peripheral does not contact the steel net 16. And direct current is applied between the steel frame cage 14 and the steel net 16 so as for the steel frame 16 to become anode. Then solid particles of bentonite or the like suspended in mud water 12 transfer to the anode steel net 16 side to form a lubricating layer 18 by an electrophoresis phenomenon. When concrete 20 is placed into the excavated hole 10 to bury the steel nets 16, it removes a negative frictional force of a cast-in-place pile due to te lubricating layer 18 between the cast-in-place pile and the inner wall of the excavated hole 10.