Grades

F1554

This ASTM specification was introduced in 1994 and covers anchor bolts that are designed for concrete foundation applications for structural support. This specification allows the bolts to conform to a headed bolt, straight rod or bent anchor bolt configuration. There are three grades within this specification, 36, 55, and 105. These grade numbers represent the minimum yield strength (KSI) requirement of the anchor bolt. The bolts are color coded at the end to easily identify the grade used in the field (Grade 36: Blue, Grade 55: Yellow, Grade 105: Red). Most Departments of Transportation will also require the supplemental requirements S2 and S3 in which the permanent grade symbol and manufacturer’s logo are stamped on the end of the anchor bolt projecting from the concrete.

Grade 36

This grade of F1554 is manufactured from A36 round bar which is a low carbon steel. These anchor bolts are standard, run-of-the-mill anchor bolts which cover a range of diameters from 1/4″ through 4”. In August of 2007, F1554 Grade 36 replaced ASTM A307 Grade C, which also covered low-carbon, mild steel anchor bolts. Because Grade 36 is manufactured from mild steel, it is always weldable.

*Note: When Grade 36 is specified, a weldable, Grade 55 specification may be furnished as a substitution at the supplier’s option.

Mechanical Requirements

Grade Identification Size, Inches Tensile, ksi Yield, ksi min Yield, MPa min Elong. % min Reduction of Area %, min
36 ASTM F1554 Grade 36 1/2 - 4 58 - 80 36 248 23 40
1Color coding (blue) is required while permanent stamping with manufacturer's identification and grade designation are supplementary requirements.

Nuts and Washers

GRADE IDENTIFICATION SIZE, INCHES RECOMMENDED A563 NUT WASHER
PLAIN FINISH HOT-DIP OR MECHANICAL ZINC COATED
GRADE STYLE GRADE STYLE
36 ASTM F1554 Grade 36 1/2 - 1-1/2 A Hex A Hex F436
1-5/8 - 4 A Heavy Hex A Heavy Hex
For additional compatible nuts see the Nut Compatibility Chart.

Grade 55

ASTM F1554 Grade 55 anchor bolts are made from a modified mild steel which has a higher minimum yield strength (55 KSI) in comparison to F1554 Grade 36 (36 KSI). This is the most common specification used for bent anchor bolts in the lighting and traffic signal industry. Engineers tend to like this specification over F1554 Grade 36 because of its higher yield strength and mechanical properties.

Grade 55 is not always weldable. If the anchor bolt needs to be weldable, the customer and/or engineer must specify supplementary requirement S1. All of the grade 55 round bar that Portland Bolt stocks will meet the S1 weldability requirements. Be wary of fastener distributors and manufacturers with limited manufacturing capabilities who attempt to substitute A193 Grade B7 or 1045 round bar for F1554 Grade 55. Those materials may exceed the requirements of Grade 55 for tensile and yield strengths but the elongation and reduction of area requirements will typically not be met. Often times, these distributors and manufacturers will try to substitute the F1554 Grade 55 anchor bolt because Grade 55 round bar is not commonly available through local warehouses. Portland Bolt buys mill runs of round bar and stocks this material for immediate processing.

Mechanical Requirements

Grade Identification1 Size, Inches Tensile, ksi Yield, ksi min Yield, MPa min Elong. % min Reduction of Area %, min
55 ASTM F1554 Grade 55 1/4 – 2 75 – 95 55 380 21 30
2-1/4 – 2-1/2 75 – 95 55 380 21 30
2-3/4 – 3 75 – 95 55 380 21 30
3-1/4 – 4 75 – 95 55 380 21 30
1Color coding (yellow) is required while permanent stamping with manufacturer’s identification and grade designation are supplementary requirements.

Nuts and Washers

Grade Identification Size, Inches Recommended A563 Nut Washer
Plain Finish Hot-Dip or Mechanical Zinc Coated
Grade Style Grade Style
55 ASTM F1554 Grade 55 1/2 – 1-1/2 A Hex A Heavy Hex F436
1-5/8 – 4 A Heavy Hex A Heavy Hex
For additional compatible nuts see the Nut Compatibility Chart.

Grade 105

This grade of F1554 anchor bolts is made from a medium carbon alloy steel which has been quenched and tempered (heat treated) to develop the required mechanical properties of the specification. This is the highest strength grade of the F1554 specification and it has a minimum yield strength of 105 KSI. It covers anchor bolts ranging 1/4″ through 3” in diameter. Portland Bolt receives calls frequently asking whether this grade can be galvanized. It can, in fact, be hot-dip galvanized and the galvanizing process does not affect the mechanical properties of the anchor bolts and it will not cause hydrogen embrittlement.

Mechanical Requirements

Grade Identification Size, Inches Tensile, ksi Yield, ksi min Yield, MPa min Elong. % min Reduction of Area %, min
105 ASTM F1554 Grade 105 1/2 – 3 125 – 150 105 724 15 45
1Color coding (red) is required while permanent stamping with manufacturer’s identification (S2) and grade designation (S3) are supplementary requirements.

Nuts and Washers

Grade Identification Size, Inches Recommended A563 Nut Washer
Plain Finish Hot-Dip or Mechanical Zinc Coated
Grade Style Grade Style
105 ASTM F1554 Grade 105 1/2 – 1-1/2 D1 Heavy Hex DH2 Heavy Hex F436
1-5/8 – 3 DH2 Heavy Hex DH2 Heavy Hex
1 A563 grade D nuts are rarely available. A563 grade DH or A194 grade 2H should be substituted.
2 The availability of A563 grade DH nuts in nominal sizes 1″ and larger is very limited and generally available only on special orders of 50,000 or more. For smaller quantities, ASTM A194 grade 2H should be considered.

A449

The A449 specification is manufactured from a medium carbon or alloy steel which undergoes a heat treating process in order to develop its full mechanical properties. It is virtually identical to ASTM A325 and SAE J429 Grade 5 in chemistry and strength, however, A449 has more flexibility due to the fact that it covers a larger range of diameters and it is not restricted by a particular configuration. This specification is commonly used as an anchor bolt for the lighting industry due to the higher-strength mechanical properties and its ability to conform to multiple configurations.

Mechanical Properties

Size Tensile, ksi Yield, ksi Elong. %, min RA %, min
14 - 1 120 min 92 min 14 35
118 - 112 105 min 81 min 14 35
158 - 3 90 min 58 min 14 35

A307A

This specification covers carbon steel bolts and studs ranging from 1/4″ to 4” in diameter. The A307 specification is considered to be the everyday, standard bolt specification which is often made from A36 steel round bar. There are three grades which fall under this specification, though only two are applicable to the lighting industry. The A307 Grade A specification is intended for headed bolts, threaded rods and bent bolts intended for general applications. The A307 Grade C specification is an old anchor bolt specification that was officially replaced by F1554 Grade 36 in 2007.

Although the A307 Grade A can be manufactured as an anchor bolt, it is technically not an anchor bolt specification. This specification is designed for general applications, whereas the F1554 specification is specifically intended for anchor bolt use. It is very common for engineers and other authorities to still specify these two grades (A307 Grades A & C) as anchor bolts in the lighting industry. Sometimes it is due to outdated plans when the F1554 specification didn’t exist, and other times it’s due to the simple fact that F1554 is still a fairly recent specification and is not always known by engineers and/or other authorities within the field. If your project must have an A307 anchor bolt, it can be manufactured, but in most scenarios, it is recommended to move to the F1554 specification which has more information and regulation on the manufacturing of anchor bolts.

A307 Mechanical Properties

Grade Tensile, ksi Yield, min, ksi Elong %, min
A 60 min -- 18
B 60 - 100 -- 18
C* 58 - 80 36 23

A307 Chemical Properties

Element Grade A Grade B
Carbon, max 0.29% 0.29%
Manganese, max 1.20% 1.20%
Phosphorus, max 0.04% 0.04%
Sulfur, max 0.15% 0.05%