Shear strength is defined as the maximum pull in psi (pounds per square inch) a fastener is capable of developing before it breaks.

Pounds per square inch Tensile strength of a material is the maximum amount of tensile stress that it can take before failure. psi is the unit of Tensile strength and it stands for Pounds per square inch.

Tensile strength is a measurement of the force required to pull something such as rope, wire, or a structural beam to the point where it breaks. The tensile strength of a material is the maximum amount of tensile stress that it can take before failure, for example breaking.

Yield Strength is the stress a material can withstand without permanent deformation or a point at which it will no longer return to its original dimensions (by 0.2% in length). Whereas, Tensile Strength is the maximum stress that a material can withstand while being stretched or pulled before failing or breaking.

Yield strength is measured in N/m² or pascals. The yield strength of a material is determined using a tensile test. The results of the test are plotted on a stress-strain curve. The stress at the point where the stress-strain curve deviates from proportionality is the yield strength of the material.

Calculating Yield & Tensile Strength

1. Yield Strength. Take the minimum yield in psi of the ASTM grade (see our Strength Requirements by Grade Chart for this value), multiplied by the stress area of the specific diameter (see our Thread Pitch Chart).
2. Ultimate Tensile Strength.
3. Shear Strength.

The most common engineering approximation for yield stress is the 0.2 percent offset rule. To apply this rule, assume that yield strain is 0.2 percent, and multiply by Young’s Modulus for your material: σ = 0.002 × E /sigma = 0.002/times E σ=0.

As yield strength is related to deformation which is a result of applied stress, the SI unit of yield strength is N.m-2. In CGS system, the yield strength is g.cm-2.

The definition of a strain is a bodily injury due to overexertion or an excessive demand on resources. An example of strain is a pulled muscle. An example of strain is reading a book in the dark, causing pressure on the eyes.

Common Strain Injuries

• Hamstring Strain.
• Quadriceps Muscle Contusion.
• Calf Strain.
• Groin Strain.
• Rotator Cuff Tears.
• Rupture Long Head Biceps.
• Achilles Rupture.

Stress is the force applied to a material, divided by the material’s cross-sectional area. Strain is the deformation or displacement of material that results from an applied stress.

When a rock is subjected to increasing stress it passes through 3 successive stages of deformation. Elastic Deformation — wherein the strain is reversible. Ductile Deformation — wherein the strain is irreversible. Fracture – irreversible strain wherein the material breaks.

Tensional stress is the stress that tends to pull something apart. It is the stress component perpendicular to a given surface, such as a fault plane, that results from forces applied perpendicular to the surface or from remote forces transmitted through the surrounding rock.

Tensional stress, sometimes known as extensional stress, stretches and pulls rocks apart. A prime example of tensional stress is the mid-Atlantic ridge, where the plates carrying North and South America are moving west, while the plates carrying Africa and Eurasia are moving east.

Answer: Powerful earthquakes tend to strike areas where compressive stress is at work, such as in Chile where the Nazca and South American plates are smashing into each other, or near Japan where the Eurasian plate and Philippine plates are ramming against one another.

Since the rock cannot move, it cannot deform. This is called confining stress. Compression squeezes rocks together, causing rocks to fold or fracture (break) (Figure below). Compression is the most common stress at convergent plate boundaries.

extensional stresses

Strike-slip faults are distinct from the previous two because they don’t involve vertical motion. They form via shear stress.

There are three kinds of faults: strike-slip, normal and thrust (reverse) faults, said Nicholas van der Elst, a seismologist at Columbia University’s Lamont-Doherty Earth Observatory in Palisades, New York.

An earthquake is caused by a sudden slip on a fault. When too much pressure builds, massive chunks of the Earth move and release intense energy. This results in waves that travel through the Earth’s outer crust to cause the shaking during an earthquake.

Faults are commonly considered to be active if there has been movement observed or evidence of seismic activity during the last 10,000 years. Active faulting is considered to be a geologic hazard and related to earthquakes as a cause.