Name: axial load stress on inclined sections
Uploaded: 2024-03-07T13:22:32.000Z
Duration: 1 min 16 s
Channel: JoVE

Si consideri un'asta soggetta a forze assiali. Introdurre un piano di sezione inclinato rispetto al piano normale, chiamato piano obliquo.
Le sollecitazioni agenti su questo piano obliquo possono essere risolte in due componenti: normale e tangenziale alla sezione.
La componente normale rappresenta la risultante delle forze normali distribuite sulla sezione, mentre la componente tangenziale rappresenta la risultante delle forze di taglio.
Le sollecitazioni medie normali e di taglio possono essere calcolate dividendo le forze normali e tangenziali per l'area della sezione.
La sollecitazione normale è massima quando il piano della sezione è perpendicolare all'asse dell'asta e si avvicina a zero quando il piano della sezione è parallelo all'asse.
La sollecitazione di taglio è massima quando il piano di sezione è inclinato di 45 gradi e si avvicina allo zero quando il piano di sezione è parallelo o perpendicolare all'asse dell'asta.
A seconda dell'orientamento del piano, lo stesso carico può produrre una sollecitazione normale senza sollecitazione di taglio o sia sollecitazioni normali che di taglio di uguale entità.

tensione su un piano obliquo

Stress on an Oblique Plane

Comprendere la tensione su un piano obliquo sottoposto a carico assiale, è fondamentale nella meccanica dei materiali. Questa analisi offre informazioni sulla durabilità e la resistenza di un materiale, che sono cruciali per l'ingegneria civile e la progettazione strutturale. Il carico assiale si riferisce all'applicazione della forza lungo l'asse centrale del materiale, causando compressione o allungamento e portando a uno sforzo normale. Lo sforzo normale si verifica quando una forza agisce perpendicolarmente all'area del materiale, provocando una sollecitazione da compressione o trazione. Quando il piano di sollecitazione non è perpendicolare al carico, è un piano obliquo e lo stato di sollecitazione include sia lo sforzo normale che quello di taglio. Lo sforzo di taglio si verifica quando la forza agisce parallelamente all'area, deformando la forma del materiale senza variazione di volume.

Considerando un elemento a due forze soggetto ad una forza assiale P ed esaminando una sezione formante un angolo θ rispetto al piano normale, le tensioni su tale piano obliquo possono essere suddivise in componenti normali (F) e tangenziali (V). Dividendo F e V per l'area della sezione, si ottengono le tensioni medie normali e di taglio. L'orientamento del piano influisce in modo significativo sullo stato di sollecitazione del materiale. A seconda dell'orientamento del piano, lo stesso carico può indurre solo sollecitazioni normali o sia sollecitazioni normali che di taglio di uguale entità. Tale comprensione è fondamentale per progettare strutture robuste ed efficienti.

Tensione su un piano obliquo

Si consideri un'asta soggetta a forze assiali. Introdurre un piano di sezione inclinato rispetto al piano normale, chiamato piano obliquo.
Le sollecitazioni che agiscono su...

Education

Didattica

JoVE Core

Mechanical Engineering

Ingegneria Meccanica

Unit 1

Unità 1

Concept of Stress

Concetto di stress

KEY TERMS AND CONCEPTS

TERMINI E CONCETTI CHIAVE

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 volume.

A two-force member under an axial force P can be cut by a section at an angle θ to the normal plane. The force on that section can be resolved into a normal component F and a tangential component V. Dividing F and V by the section area gives the average normal stress and average shearing stress.

The orientation of the plane strongly changes the stress on the material. For some angles, the same load produces only normal stress. For other angles, it produces both normal and shearing stress, and these stresses may be equal in magnitude. This idea is important in civil engineering and structural design, where strength and durability matter.

Axial Load Stress on Inclined Sections

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

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...

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 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 axial loading creates normal and shearing stress on inclined sections, and how plane angle changes the stress state in materials.

Axial Load Stress on Inclined Sections | JoVE K12

JoVE Core Mechanical Engineering offers concise, easy-to-understand animated videos covering key topics such as equilibrium, forces, truss analysis, and structural mechanics. Explore their real-world applications, and witness these concepts in action through scientist-led experiments.

mechanical engineering

Axial Load Stress on Inclined Sections

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