US3579931A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Method for post-tensioning tendons
Assignee: EIDP Inc
•
Filing: 1969-09-18
•
Granted: 1971-05-25
•
Expires: 1989-09-18
Abstract
Abstract An anchoring system is provided wherein the end of a posttensioned tendon extending from a concrete structure is encased in a metallic sheath and the sheath is crimped in a series of reversals of increasing angularity in the direction away from the concrete structure.
Inventors
- 👤 Frederic A Lang
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-28 13:03
CPC Classifications
E; E04; E04C; E04C5/00; E04C5/08; E04C5/12; Y; Y10; Y10T; Y10T29/00; Y10T29/49; Y10T29/49616; Y10T29/49623; Y10T29/49632; Y10T29/49826; Y10T29/49863; Y10T29/49874
Claims Analysis
Total Claims: 6
Claim 1
Independent Claim
77 words
A process for anchoring an end of a post-tensioning tendon which protrudes from a concrete structure so as to place said structure under compression, comprising encasing said end of said tendon in a sheath, tensioning said tendon and crimping said sheath and said tensioned tendon encased thereby in a series of reversals of increasing angularity in the direction away from said concrete structure sufficiently to maintain said tendon in the tensioned condition upon release of said tensioning.
Claim 2
Dependent Claim
77 words
A process for anchoring an end of a post-tensioning tendon which protrudes from a concrete structure so as to place said structure under compression, comprising encasing said end of said tendon in a sheath, tensioning said tendon and crimping said sheath and said tensioned tendon encased thereby in a series of reversals of increasing angularity in the direction away from said concrete structure sufficiently to maintain said tendon in the tensioned condition upon release of said tensioning.
Claim 3
Dependent Claim
22 words
In the process of claim 1 placing a bearing plate between the sheath and the concrete structure to distribute the compressive force.
Claim 4
Dependent Claim
36 words
In the process of claim 1 using a tendon which is made of steel wire having an elastic limit of at least 150,000 p.s.i. and using a sheath which is a tubing of annealed stainless steel.
Claim 5
Dependent Claim
41 words
In the process of claim 1 using a tendon which is made of cold drawn carbon steel wire having an elastic limit of at least 150,000 p.s.i. and using a sheath which is a tubing of annealed stainless steel No. 410.
Claim 6
Dependent Claim
61 words
In the process of claim 1 using a tendon which is made by tightly and uniformly coating a steel wire having an elastic limit of at least 150,000 p.s.i. with a plastic material, there being a coefficient of friction no greater than 0.09 between the wire and the coating, and using a sheath which is a tubing of annealed stainless steel.
References Cited (Backward Citations)
GB550267A
Cited
US3007284A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1974-05-24 | 1974-11-23 | 1975-05-25 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1978-05-24 | 1978-11-23 | 1979-05-25 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1982-05-24 | 1982-11-23 | 1983-05-25 | $7700.00 | Window Closed / Lapsed |