Method and apparatus for detecting tendon failures within prestressed concrete

Patent 6119526 Issued on September 19, 2000. Estimated Expiration Date:

July 15, 2018. Estimated Expiration Date is calculated based on simple USPTO term provisions. It does not account for terminal disclaimers, term adjustments, failure to pay maintenance fees, or other factors which might affect the term of a patent.

Abstract Claims Description Full Text

Patent References

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Inventors

Assignee

Tech Research, Inc.

Application

No. 116034 filed on 07/15/1998

US Classes:

73/803, Concrete324/218Rail joint cutout

Examiners

Primary: Noori, Max

Attorney, Agent or Firm

Merchant & Gould P.C.

International Class

G01N 003/00

Abstract

A nondestructive detection apparatus for detecting tendon failures in a prestressed concrete slab. The detection apparatus includes a cart adapted to be moved over the prestressed concrete slab. A metal sensor and a distance meter are connected to the cart. As the cart is moved over the slab, the metal sensor takes readings of a length of tendon and the distance meter measures the distance traversed by the cart. The detection apparatus also includes a controller that interfaces with the metal sensor and the distance meter. The controller is constructed and arranged to sample the readings generated by the metal sensor at predetermined distance intervals traversed by the cart.

Other References

Rotary Shaft Encoder #380, Electro-Sensor, Inc., pp. 1-4, Published before the filing date of the present application
Redar Datascan C-4974, NDT James Instruments, Inc., pp. 1-15, Published before the filing date of the present applicatio