Can ASTM A325 grade be used as anchor bolts?
We often sell A325 heavy hex bolts as anchor bolts, but technically they are supposed to be used for structural steel connections only. Part of the problem is that the A325 specification is very specific as to the application and thread length. Because A325 bolts are typically used in structural steel connections, they have very short thread lengths. Often this thread length restriction is too short when the bolts are used as anchor bolts. The A325 specification recommends switching to A449 when being used as an anchor bolt. ASTM A449 is virtually identical in chemistry and strength, but can have longer thread length and is not restricted by the application. When engineers do specify A325 heavy hex bolts to be used as anchor bolts, we will typically extend the thread length (in agreement with the customer) beyond what the specification calls for. We also frequently see bent anchor bolts and straight anchor rods with anchor plates ordered to the ASTM A325 specification. Since the A325 specification is restricted to heavy hex structural bolts only, once again ASTM A449 should be considered in lieu of A325. AISC also discusses what ASTM specifications should be used as anchor bolts.