F1554 Tensile Strength Range

[BigH]

Have a bit of a dilemma; contractor is proposing an anchor bolt to F1554 to Grade 55 - straightforward. However, when reviewing the mill cert, the tensile test result is 675 MPa. The specification, Table 3 gives a range of 517 to 655 (now why 517 and not 515? - conversion, I gather).

The dilemma is would one accept this material even though it has a tensile strength 20 MPa higher than the maximum given in the specification? We are in a tropical climate with temperatures seldom dropping below 24degC.

As a parallel query - why do they give a range rather than just a minimum strength? What is the significance of the range?

With

 

[TXStructural]

I do not know about F1554, but on many structural elements (A706 rebar, A992 beams) used in seismic design, there a maximum yield to assure that when something is designed to fail (as a fuse in the structure) that it will in fact fail predictably. For rebar, it is an 18 ksi (124 MPa) range - pretty close to the 138 MPa in your example. It is a bit counterintuitive, but I can imagine a designer might want the anchorage to yield before the pier or footing fails catastrophically.

 

[dik]

Is that the yield for the mill cert or the UTS?

Dik