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A307 Anchor Bolt -

| Prohibited or Dangerous Application | Reason | | :--- | :--- | | in seismic zones (D, E, F) | Lack of guaranteed strain-hardening capacity and impact toughness. | | High-tension bracing connections (e.g., tension-only braced frames) | Steel tensile failure may occur before concrete breakout, leading to brittle collapse. | | Epoxy-grouted or adhesive anchors under sustained tension | A307 bolts have no surface treatment spec; smooth surface reduces bond strength. Adhesive manufacturers often require F1554. | | Shear lugs with tension (combined loading >20% of capacity) | Low shear strength relative to higher-grade bolts. | | Post-installed anchors in overhead life-safety applications | IBC prohibits unless specifically tested per ACI 355.2. A307 rarely qualifies. |

Note: Unlike F1554, A307 does not mandate a specific yield strength; instead, it relies on tensile strength and bend tests. However, the base material (A36) ensures a yield floor of 36 ksi. a307 anchor bolt

| Error | Correction | | :--- | :--- | | Specifying "A307 anchor bolt" without grade | Write: ASTM A307, Grade A, low-carbon steel, plain finish, 36 ksi min yield, 60 ksi min tensile. | | Using A307 in epoxy anchors | Specify F1554 Grade 36 or 55 for adhesive anchoring. | | Omitting bend radius for L-bolts | Minimum inside bend radius = 2 × bolt diameter. | | No corrosion allowance | Add: Hot-dip galvanize per ASTM A153, unless noted otherwise. | | Prohibited or Dangerous Application | Reason |

| Environment | Required Protection | | :--- | :--- | | | As-rolled (plain) acceptable | | Exterior, moderate | Hot-dip galvanized per ASTM A153 (minimum 2.0 oz/ft²) | | Coastal/marine | Stainless steel (Type 304 or 316) – A307 spec does not apply; use F1554 | | Embedded in concrete | No coating required (alkaline passivation) – but cutoff must be above ground | Adhesive manufacturers often require F1554

| Property | Value | | :--- | :--- | | | 60 ksi (414 MPa) minimum | | Yield Strength | 36 ksi (248 MPa) minimum (typical, not mandatory by ASTM but implied by material) | | Elongation | 18% minimum (in 8 in.) – High ductility | | Hardness | Brinell 100–241 | | Threads | UNC series (Class 1A or 2A) | | Material | Low-carbon steel (e.g., A36, 1018) |

Do not use mechanically galvanized or electroplated coatings for embedded anchor bolts—hydrogen embrittlement risk is elevated for low-carbon bolts.