Anchor for post tension concrete reinforcing systems
An anchor for a post tension reinforcement includes an anchor base having at least one wedge receiving bore therein and reinforcing ribs extending from an exterior of the receiving bore. A longitudinal length of the wedge receiving bore, a position of a midpoint of an axial length of the wedge receiving bore with respect to a load bearing basal surface of the anchor base, and a lateral extension and height of the ribs are selected such that a specific weight of the anchor base is at most 0.1 pounds per square inch of load bearing area.
1. An anchor for a post tension concrete reinforcement, comprising:
an anchor base having at least one wedge receiving bore therein and reinforcing ribs extending laterally from an exterior of the receiving bore to the anchor base, a longitudinal length of the wedge receiving bore, a position of a midpoint of an axial length of the wedge receiving bore with respect to a load bearing basal surface of the anchor base, and a lateral extension and height of the ribs selected such that a specific weight of the anchor base is at most 0.1 pounds per square inch of load bearing area.
2. The anchor of claim 1 wherein the anchor base has a specific weight of at most
W
=
0.10
×
(
d
t
0.5
)
wherein W represents the approximate limit of the specific weight in pounds per square inch of load bearing area, and d t represents a nominal diameter of the tendon for which the anchor base is sized.
3. The anchor of claim 2 wherein the load bearing area of the anchor is selected to be at least an amount adapted to conform to post-tension acceptance standards.
4. The anchor of claim 1 wherein the wedge receiving bore is tapered in diameter at a single selected taper angle, the taper extending substantially continuously from a first end of the bore to a second end of the bore, an axial length of the wedge receiving bore selected so that a minimum internal diameter of the wedge receiving bore is at least one half of the axial length.
5. The anchor of claim 1 wherein a load bearing basal surface of the anchor base is disposed substantially at a midpoint of the axial length of the wedge receiving bore.
6. The anchor of claim 1 wherein the single selected taper angle is seven degrees.
7. The anchor of claim 1 wherein the axial length is at most 1.3 times a maximum internal diameter of the wedge receiving bore.
8. The anchor of claim 1 wherein a height of reinforcing ribs is at most 0.35 times a maximum internal diameter of the wedge receiving bore.
9. The anchor of claim 2 wherein at least one rib terminates at a position between 0.03 to 0.1 times a longest transverse dimension of the anchor base.
10. The anchor of claim 1 wherein the anchor base includes at least four mounting holes.