Pre-stressed concrete structures
AssigneeSimonbuild Limited
InventorWalter Thorpe
Life of this patent
Estimating the term…
Abstract
A method of installing a tendon in a duct in a slip-formed concrete structure including the steps of providing a tubular member which forms the uppermost part of the duct and whose upper end terminates at the level where the upper end of the tendon is to be anchored, said tubular member having outwardly extending abutment means at or adjacent its lower end, said abutment means being of such size and at such depth below the upper end of the tubular member as to enable the forces necessary to instal and support a tendon in the duct, at the time when the concrete structure reaches a height in the vicinity of the upper end of said tubular member, to be transmitted through the tubular member and distributed to the concrete structure by the abutment means at a level where the concrete has gained adequate strength for this purpose.
Claims8
A method of installing a tendon in a longitudinally extending duct in an elongated generally vertical concrete structure while said structure is being slip-formed comprising the steps of providing a tubular member to form the uppermost part of said duct, said member having a laterally outwardly extending abutment at or near its lower end and being of such length that its upper end terminates at the level where the upper end of a tendon is to be anchored with said abutment so spaced below said upper end of the tubular member that, a the time the upwardly growing concrete structure reaches a height in the vicinity of said upper end, said abutment is located within the structure at an operative level where the concrete has sufficiently hardened and developed sufficient strength to enable forces necessary to install and support a tendon in the duct to be transmitted through the tubular member and abutment to be distributed in the developed concrete structure at that operative level.
Equipment for installing a tendon in a longitudinally extending duct in an elongated generally vertical concrete structure while said structure is being slip-formed comprising a tubular member adapted to be inserted to form the uppermost part of said duct, said member having outwardly extending abutment means at or near its lower end and being of such length that its upper end terminates at the level where the upper end of a tendon is to be anchored with said abutment means so spaced below said upper end of the tubular member that, at the time the upwardly growing concrete structure reaches a height in the vicinity of said upper end, said abutment means is located within the structure at an operative level where the concrete has sufficiently hardened and developed sufficient strength to enable forces necessary to install and support a tendon in the duct to be transmitted through the tubular member and abutment means to be distributed in the developed concrete structure at that operative level, said member having a bearing plate for a prestressing tendon at its said upper end.
Dependencies are inferred from the claim text.