What is the shear strength of a bolt?
Daniel Rodriguez
Published Feb 13, 2026
What is the shear strength of a bolt?
The shear strength of a bolt is a measurement of the minimum amount of force needed to break the bolt into two pieces. The shear strength of a metal bolt is approximately 0.6 times its tensile strength. A bolt commonly shears where its head meets the threads.
How do you calculate the shear strength of a bolt?
The shear strength of all bolts = shear strength of one bolt x number of bolts • The bearing strength of the connecting / connected plates can be calculated using equations given by AISC specifications. The tension strength of the connecting / connected plates can be calculated as discussed earlier in Chapter 2.
What grade bolt has the highest shear strength?
Grade 8 bolts exhibit greater tensile, yield, and shear strength as well as greater fatigue resistance and, just as important, are capable of greater torque specs and therefore much greater pre-load and clamping strength.
What is the shear strength of a 12mm bolt?
Grade 8.8 Bolt Loading Capacities Table
| Diameter of Bolt | Tensile Stress Area At | Shear Capacity |
|---|---|---|
| mm | mm2 | kN |
| 12 | 84.3 | 31.6 |
| 16 | 157 | 58.9 |
| 20 | 245 | 91.9 |
What is the shear strength of 3/8 bolt?
A 3/8-inch bolt of this type is rated to 7,000 pounds in 6,000 psi concrete (basically granite) and 4,000 pounds in 2,000 psi concrete (hard sandstone).
What is the shear strength of 1/4 20 bolt?
Material Strength – 60,000 psi J82 60M or Grade 1 or Class 4.8
| Size | Dia. | Tensile Str. Lbs |
|---|---|---|
| 10-32 | 0.1900 | 1,200 |
| 1/4-20 | 0.2500 | 1,908 |
| 1/4-28 | 0.2500 | 2,182 |
| 5/16-18 | 0.3125 | 3,144 |
What does 8.8 mean on the head of a bolt?
So, in English, a PC 8.8 bolt is a bolt with a nominal tensile strength of 800 MPa and a nominal yield strength that is 80% of the bolt’s nominal tensile strength, or 640 MPa.
How much weight can a 12mm bolt hold?
| Size | Grade 8.8 | Grade 10.9 |
|---|---|---|
| M12 | 4,890kg | 7,000kg |
| M16 | 9,100kg | 13,000kg |
| M20 | 14,700kg | 20,300kg |
| M24 | 21,200kg | 29,300kg |
What is thread shear area?
The shear strength is defined by Fs=τ Ath where τ = shear strength of the material and Ath the thread shear area. When the external and internal thread are of the same material, the internal thread (in the tapped hole) is stronger in shear than the external thread.
What is the break strength of a 3/8 grade 8?
Proof Load
| Nom Bolt Size (in) | Grade | |
|---|---|---|
| 2 | 8 | |
| 3/8 | 4250 | 9300 |
| 7/16 | 5850 | 12800 |
| 1/2 | 7800 | 17000 |
How much weight can a 1/4 20 bolt hold?
Material Strength – 60,000 psi J82 60M or Grade 1 or Class 4.8
| Size | Dia. | Proof Load Str. Lbs |
|---|---|---|
| 10-32 | 0.1900 | 660 |
| 1/4-20 | 0.2500 | 1,049 |
| 1/4-28 | 0.2500 | 1,200 |
| 5/16-18 | 0.3125 | 1,729 |
What is the tensile strength of the AN3 an3-3 airframe bolt?
The AN3-3 Airframe Bolt has a tensile strength of 125,000 psi and a shear strength of 76,000 psi. If the AN3 AN3-3 Airframe Bolt is overstressed, it will bend first rather than snapping.
What is the shear strength of a nas1103 bolt?
NAS1103 thru NAS1120 Bolt – Shear, Modified Hexagon Head Short Thread Alloy Steel Heat Treated Per MIL-H-6875 160,000 – 180,000 psi Tensile Strength 95,000 psi Minimum Shear Cadmium Plated per QQ-P-416, Type II, Class 2. Example Part#s: NAS1104-9D 1/4-28 x .878 Drilled Shank NAS1106-27 3/8-24 x 2.079 Undrilled Shank
What materials are used to make the AN3 and AN20 bolts?
AN3 thru AN20 – AIRFRAME BOLTS AN3 thru AN20 – AIRFRAME BOLTSSteel – Cadmium plated per QQ-P-416, Type II, Class 3. Aluminum Alloy. 431 Stainless Steel (CRES).
What does an3-3 airfrme mean?
The threaded end of the AN3-3 Airframe Bolt is tapered, to allow easier starting of the nut. The AN3-3 Airframe Bolt is tapered on the last threads, for ease of installation of the nut. The AN3-3 Airframe Bolt has a tensile strength of 125,000 psi and a shear strength of 76,000 psi.
