ASTM F1554 – Mechanical, Material & Chemical Properties

ASTM F1554 is the industry-standard specification for steel anchor bolts (anchor rods) intended for anchoring structural supports to concrete foundations. This covers various applications including building columns, highway sign supports, street lighting, and traffic signals.

The specification is unique because it classifies bolts based on their minimum yield strength, making it easy for engineers to select a grade that matches the structural requirements of the foundation.

Key Application Details

  • Configurations: Covers straight, bent (hooked), headed, and headless (all-thread) rods.
  • Strength Grades: Available in three grades: Grade 36 (low carbon), Grade 55 (high-strength, low-alloy), and Grade 105 (heat-treated alloy steel).
  • Diameter Range: Supports a wide range of sizes from 1/2" up to 4" in diameter (Grade 105 is limited to 3").
  • Thread Classes: Standardized for Class 1A or Class 2A threads. If not specified, Class 2A is the default.

Vital Compliance Considerations

  • Weldability: Grade 36 is considered weldable by default. Grade 55 is not weldable unless Supplementary Requirement S1 is explicitly requested.
  • Heat Treatment: Grade 105 anchor bolts must be quenched and tempered to achieve their high-strength properties.
  • Prohibited Materials: The use of low-carbon martensitic steel is strictly forbidden. Additionally, steel cannot contain intentionally added bismuth, selenium, tellurium, or lead.
  • Protective Coatings: Zinc coatings can be applied via hot-dip (ASTM F2329) or mechanical deposition (ASTM B695). Note that for zinc-coated bolts, nuts must be overtapped to accommodate the coating thickness.

Mechanical Properties

The ASTM F1554 specification defines the required mechanical properties of anchor bolts across three distinct strength levels: Grade 36, Grade 55, and Grade 105. These grades are classified primarily by their minimum yield strength, which ranges from 36 ksi to 105 ksi, providing options for varied structural loading requirements. Compliance is verified through rigorous tensile testing of either full-size finished bolts or machined specimens to ensure each rod meets specific standards for tensile strength, yield strength, elongation, and reduction of area.

Grade Classification
Grade Tensile Strength,
ksi (MPa)		 Yield Strength,
min, ksi (MPa)		 Diameter Range,
in.
36 58–80 (400–558) 36 (248) ½ – 4
55 75–95 (517–655) 55 (380) ½ – 4
105 125–150 (862–1034) 105 (724) ½ – 3
Class Description
1A anchor bolts with Class 1A threads
2A anchor bolts with Class 2A threads
Axial Tensile Properties for Full-Size Tests of Anchor Bolts and Drawn CouponsA
Nominal Diameter (in.) Threads per inch Stress Area (in.²) Grade 36 Grade 55 Grade 105
Tensile Strength (lbf) Yield min (lbf) Tensile Load (lbf) Yield min (lbf) Tensile Load (lbf) Yield min (lbf)
Unified Coarse Thread Series (UNC)
1/2 13 UNC 0.1419 8,200–11,400 5,100 10,600–13,500 7,800 17,700–21,300 14,900
5/8 11 UNC 0.226 13,100–18,100 8,100 17,000–21,500 12,400 28,200–33,900 23,700
3/4 10 UNC 0.334 19,400–26,700 12,000 25,000–31,700 18,400 41,800–50,100 35,100
7/8 9 UNC 0.462 26,800–37,000 16,600 34,600–43,900 25,400 57,800–69,300 48,500
1 8 UNC 0.606 35,200–48,500 21,800 45,400–57,600 33,300 75,800–90,900 63,600
1 1/8 7 UNC 0.763 44,300–61,000 27,500 57,200–72,500 42,000 95,400–114,400 80,100
1 1/4 7 UNC 0.969 56,200–77,500 34,900 72,700–92,100 53,300 121,000–145,000 102,000
1 1/2 6 UNC 1.405 81,500–112,400 50,600 105,000–133,000 77,300 176,000–211,000 148,000
1 3/4 5 UNC 1.90 110,000–152,000 68,400 142,000–180,000 104,500 238,000–285,000 200,000
2 4 1/2 UNC 2.50 145,000–200,000 90,000 188,000–238,000 138,000 312,000–375,000 262,000
8 Thread Series (8 UN)
1 1/8 8 UN 0.790 45,800–63,200 28,400 59,200–75,000 43,400 98,800–118,500 83,000
1 1/4 8 UN 1.000 58,000–80,000 36,000 75,000–95,000 55,000 125,000–150,000 105,000
1 1/2 8 UN 1.492 86,500–119,400 53,700 112,000–142,000 82,100 186,000–224,000 157,000
2 8 UN 2.77 161,000–222,000 99,700 208,000–263,000 152,000 346,000–416,000 291,000
A Tensile properties calculated from requirements in Table 3. Yield strength measured at 0.2% offset. Stress areas extracted from ASME B 1.1
Tensile Properties for Bars and Machined Specimens
Property Grade 36 Grade 55 Grade 105
Tensile strength, ksi 58–80 75–95 125–150
Yield strength, min, ksi (0.2% offset) 36 55 105
Elongation in 8 in., min, %A 20 18 12
Elongation in 2 in., min, % 23 21 15
Reduction of Area, min, % 40 30 45
A Elongation in 8 in. applies to bars. Elongation in 2 in. applies to machined specimens.

Material Properties

The material properties of ASTM F1554 anchor bolts are defined by strict chemical composition requirements that ensure structural integrity and, where specified, weldability. These standards establish maximum limits for elements like carbon, manganese, phosphorus, and sulfur to maintain the necessary balance between strength and ductility. Notably, the specification strictly prohibits the use of low-carbon martensitic steel and materials containing intentionally added bismuth, selenium, tellurium, or lead.

Chemical Composition
Element Type Grade 36 Grades 55 and 105
Diameters up to ½, incl. Over ½ to 4, incl. All Diameters
Carbon, max, % Heat 0.25 0.25 —
Product 0.28 0.28 —
Manganese, max, %A Heat — 0.90 —
Product — 0.98 —
Phosphorus, max, % Heat 0.04 0.04 0.04
Product 0.05 0.05 0.048
Sulfur, max, % Heat 0.05 0.05 0.05
Product 0.06 0.06 0.058
Copper, min, %
(when specified)		 Heat 0.20 0.20 0.20
Product 0.18 0.18 0.18
A For each reduction of 0.01% below the specified Carbon maximum, an increase of 0.06% Manganese above the specified maximum is permitted, up to a maximum of 1.35% Mn.