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Long-length high-strength steel rods with splices

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I have a design for which I'd like to specify ASTM A449 round plain rods with 
upset threaded ends.  The total length of each rod assembly is about 35 feet. 
 

The rods are expected to yield in a strong seismic event, and I want the 
yielding to occur in the un-threaded portion with the expectation that the 
ductility is better there because the yielding may be distributed over most 
of the length of the rod rather than being confined to the limited lengths of 
the threaded portions.  Also, it seems that yielding of steel in the threaded 
portions is likely to be more brittle because yielding can only occur at the 
zone of minimum cross sectional area at the base of the threads. 

I am visualizing the welding of larger diameter threaded ends to lengths of 
smaller diameter plain rod.  The footnote to AISC Table 1-C states that A449 
steel, which is quenched and tempered carbon steel, should not be welded, and 
suggests using an appropriate steel (such as AISI C1040 or C4140), quenched 
and tempered after fabrication.

Is quenching and tempering of fabricated assemblies as long as 35 ft 
practical? 

Are there fabricators in the Southern California region who do it and with 
whom I can discuss materials and workmanship items as I prepare my 
specifications? 

Nels Roselund
Structural Engineer