초록 ▼

A hollow, cylindrical pier foundation is constructed of cementitious material poured in situ between inner and outer cylindrical corrugated metal pipe shells. The foundation is formed within a ground pit and externally and internally back filled. The lower end of the foundation has a circumferential

A hollow, cylindrical pier foundation is constructed of cementitious material poured in situ between inner and outer cylindrical corrugated metal pipe shells. The foundation is formed within a ground pit and externally and internally back filled. The lower end of the foundation has a circumferential ring fully embedded therein and sets of inner and outer circumferentially spaced bolts have their lower ends anchored to the anchor ring, their upper ends projecting up outwardly of the top of the foundation and a majority of the midportions thereof free of connection with the cementitious material of which the foundation is constructed. The base flange of a tubular tower is positioned downwardly upon the upper end of the foundation with the upper ends of the inner and outer sets of bolts projecting upwardly through holes provided therefor in the base flange and nuts are threaded downwardly upon the upper ends of the bolts and against the base flange. The nuts are highly torqued in order to place the bolts in heavy tension and to thus place substantially the entire length of the cylindrical foundation in heavy axial compression.

대표청구항 ▼

A pier foundation subject to high upset forces which comprises a hollow, upright cylindrical structure of heavy post-compressed cementitious material under high compressive loading from the upper end thereof downwardly to a level adjacent the lower end thereof and having open top and bottom ends, a

A pier foundation subject to high upset forces which comprises a hollow, upright cylindrical structure of heavy post-compressed cementitious material under high compressive loading from the upper end thereof downwardly to a level adjacent the lower end thereof and having open top and bottom ends, a plurality of metal rods and shield means surrounding said rods spaced about said cylindrical structure and extending generally vertically in said cementitious material from said level to said upper end, and tension adjusting structure operatively connected between said rods and said cylindrical structure for tensioning of said rods, said shield means shielding said rods from said cementitious material and permitting said rods to elongate relative to said cementitious material during tensioning, said rods each being heavily tensioned between said level and said upper end to post-compress said cementitious material, and said shield means continuously shielding said rods from said cementitious material to permit said rods to be retenioned as necessary.