Name: bolt-to-plate contact pressure
Uploaded: 2025-05-22T09:06:17.000Z
Duration: 1 min 22 s
Channel: JoVE

The stress exerted on a material due to the contact pressure created while interacting with another object is called bearing stress.
Consider two plates connected by a bolt. The bolt applies an internal force onto one of the plates. This internal force is equivalent yet opposite to the force that the plate exerts back onto the bolt.
Here, the internal force is not singular but a result of numerous smaller forces that are distributed across the interior surface of the half-cylinder.
Due to the intricacy of the smaller forces and the corresponding stresses, an average nominal stress, known as bearing stress is often used for simplification.
The bearing stress is calculated by dividing the internal force by the area of the rectangle that represents the projection of the bolt on the plate section. This area is the product of the thickness of the plate and the diameter of the bolt.
The concept of bearing stress is pivotal in ensuring safe and efficient structural designs and hence enhances the lifespan of the structure.

bearing stress

Bearing Stress

Bearing stress refers to the contact pressure between two separate bodies. To visualize this, imagine a bolt thrust through a plate. The bolt applies a force to the plate, which exerts an equal but opposite force back onto the bolt. This force isn't just a singular entity but a compilation of numerous smaller forces distributed across the contact surface between the bolt and the plate.
Due to the intricacy of these microforces, an average value, known as bearing stress, is often used by engineers for simplification. The bearing stress is determined by dividing the bolt's applied load by the projected area of the bolt on the plate.
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Comprehending bearing stress is an essential part of structural engineering. It gives engineers a critical understanding of how different forces interact within a structure. This knowledge is crucial when designing structures as it helps ensure the safety and efficiency of their designs.
By accurately calculating bearing stress, engineers can prevent potential failures due to excessive force and extend the structure's lifespan. In conclusion, bearing stress is a pivotal concept in structural engineering. It's a key factor in determining the durability and safety of a structure.

Bearing stress refers to the contact pressure between two separate bodies. To visualize this, imagine a bolt thrust through a plate. The bolt applies a ...

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bolt-to-plate contact pressure

Bearing stress is the contact pressure between two separate bodies. A common example is a bolt pushed through a plate. The bolt applies a force to the plate, and the plate pushes back with an equal and opposite force.

That force is not a single point load. It is made up of many smaller forces spread across the contact surface between the bolt and the plate. Because these microforces are complex, engineers use an average value called bearing stress.

Bearing stress is found by dividing the bolt’s applied load by the projected area of the bolt on the plate. This calculation helps engineers understand how forces act inside a structure. It is an important part of structural engineering because it supports safe and efficient design.

By calculating bearing stress correctly, engineers can reduce the risk of failure from too much force. It also helps them improve the lifespan of a structure. Bearing stress is a key factor in judging durability and safety.

Bolt-to-Plate Contact Pressure

normal stress

Normal Stress in Axial Loading

Normal stress acts perpendicular to a material’s cross-sectional area. It appears when a force is applied along the axis of an object, which is called axial loading. Bridge truss members are a practical example of this kind of loading. When a rod carries axial load, internal forces develop across the section. Because these forces act normal to the plane of the section, the stress is called normal stress. Stress here means the average stress over the whole cross-section, not the value at one...

shearing stress

Shear Forces in Bolts and Rivets

Shearing stress is caused by transverse forces acting on an object. These forces create internal forces in the plane where the external forces are applied. The total internal force in that section is called the shear. Average shearing stress is found by dividing the shear by the cross-sectional area. This value is only an average, because shear stress is not spread evenly across the section. It can be zero at the surface and much higher than the average in other areas. Bolts, pins, and rivets...

Bearing stress is the contact pressure between two separate bodies. A common example is a bolt pushed through a plate. The bolt applies a force to the plate, and the plate pushes back with an equal and opposite force. That force is not a single point load. It is made up of many smaller forces spread across the contact surface between the bolt and the plate. Because these microforces are complex, engineers use an average value called bearing stress. Bearing stress is found by dividing the...

applications of stress

Boom and Rod Stress Analysis

Boom and rod stress analysis shows how a pinned support structure carries a load. The boom and the rod are connected by a pin and held in place by brackets and pins. The structure is then separated from its supports so the forces can be studied clearly. A free-body diagram is drawn to identify every force on the boom, the rod, and the load. The reaction forces on both members are found using equilibrium equations. At point P, the reaction causes compression in the boom. At point R, the...

stress on an oblique plane

Axial Load Stress on Inclined Sections

Axial loading creates stress in a material along its central axis. This kind of load can cause compression or elongation, and it produces normal stress. Normal stress acts perpendicular to the material area and can be either tensile or compressive. When the section is not perpendicular to the load, it becomes an oblique plane. On this inclined plane, the stress state includes both normal stress and shearing stress. Shearing stress acts parallel to the area and changes shape without changing...

stress: general loading conditions

Stress Components on a Loaded Body

Stress components on a loaded body can be found by cutting the body through a point with a plane parallel to the xy plane. That section carries the original loads, along with normal forces and shearing forces. The result is a simple way to describe how a structure responds under combined loading. The shearing force in the section can point in different directions within the plane. It is split into two parts that run parallel to the x and y axes. Each part is divided by the area, and as that...

components of stress

Stress Components on a Cube at a Point

Stress components on a small cube help describe how a body behaves under multiple loading. The cube is centered at point O and has stress acting on all six faces, whether the faces are visible or hidden. Normal stress components σx, σy, and σz act perpendicular to the x, y, and z axes. Shearing stress components also act on the cube faces. The visible faces carry shear stresses such as τxy and τxz. The hidden faces carry equal and opposite stresses. This balance keeps the cube in equilibrium.

design consideration

Safety Factors in Structural Design

Safety factors in structural design help engineers choose a material and loading limit that can be used safely. The process begins with a material’s ultimate strength. This value comes from tests that increase force until the material reaches its breaking point or limit. The ultimate load is then divided by the original cross-sectional area to find the ultimate normal stress, or strength. Ultimate shearing stress is another key value used in design. These limits show how much stress a material...

key terms and concepts

Learn how bearing stress describes contact pressure between a bolt and a plate, how it is calculated, and why it matters in structural engineering.

Bolt-to-Plate Contact Pressure | JoVE K12

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Bolt-to-Plate Contact Pressure

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