Name: beam loads and internal forces
Uploaded: 2025-05-22T09:06:03.000Z
Duration: 1 min 14 s
Channel: JoVE

Cuando una viga se somete a diferentes cargas, se producen esfuerzos internos. Estas fuerzas se pueden determinar considerando un punto imaginario en la viga y utilizando el método de sección.
La fuerza interna que actúa perpendicular a la sección transversal de la viga se denomina fuerza normal o fuerza axial, mientras que la fuerza que actúa tangencial a la sección transversal se denomina fuerza cortante.
Estas fuerzas actúan en direcciones opuestas en cada segmento y se pueden determinar aplicando las ecuaciones de equilibrio.
Considere una viga en voladizo OB con una carga variable. Determine las fuerzas normales y cortantes que actúan en el centro de la viga.
Estas fuerzas se pueden determinar utilizando el método de sección y analizando las fuerzas en el segmento AB de la viga.
Usando el concepto de triángulos similares, se puede determinar la fuerza en el centro.
Al dibujar un diagrama de cuerpo libre y usar las ecuaciones de equilibrio, se pueden determinar las fuerzas normales y de cizallamiento.

<ol>
	<li>Hibbeler, R.C. (2016). Ingeniería Mecánica \u2012 Estática y Dinámica. Hoboken, Nueva Jersey: Pearson Prentice Hall. págs. 343-344.</li>
</ol>

fuerza normal y de corte

Cuando una viga está sujeta a diferentes cargas, como peso, presión u otras fuerzas externas, se generan fuerzas internas dentro de la viga. Estas fuerzas pueden tener un impacto significativo en la estabilidad y resistencia general de la estructura. Los ingenieros utilizan varios métodos para analizar y determinar la magnitud y dirección de estas fuerzas internas. Una técnica común utilizada para determinar las fuerzas internas en vigas es el método de secciones. Este método implica considerar un punto o sección imaginaria en la viga y analizar las fuerzas que actúan en ese punto específico. La fuerza normal, también conocida como fuerza axial, es la fuerza interna que actúa perpendicular a la sección transversal de la viga. Esta fuerza puede ser compresiva o de tracción, dependiendo de la naturaleza de la carga aplicada a la viga. Mientras tanto, la fuerza de corte es la fuerza interna que actúa tangencialmente a la sección transversal de la viga. Las fuerzas de corte funcionan en direcciones opuestas en cada segmento de la viga. Las fuerzas normales y de corte se pueden determinar aplicando las ecuaciones de equilibrio a la viga en consideración. Comprender las fuerzas normales y de corte es crucial en ingeniería estructural, ya que estas fuerzas desempeñan un papel importante en la determinación de la estabilidad, resistencia y rendimiento general de las vigas y otros elementos estructurales. Utilizando el método de secciones y las ecuaciones de equilibrio, los ingenieros pueden determinar con precisión las fuerzas internas dentro de las vigas y diseñar estructuras que puedan soportar las cargas y tensiones encontradas durante su vida útil de servicio.

Fuerza normal y de corte

Cuando una viga está sometida a diferentes cargas, como peso, presión u otras fuerzas externas, se generan fuerzas internas dentro de la viga. Estos...

Education

Educación

JoVE Core

Mechanical Engineering

Ingeniería Mecánica

Unit 1

Unidad 1

Internal Forces

Fuerzas internas

KEY TERMS AND CONCEPTS

TÉRMINOS Y CONCEPTOS CLAVE

Normal and Shear Force

beam loads and internal forces

Beam loads create internal forces inside a structure. Weight, pressure, and other external forces can all act on a beam. These internal forces affect the beam’s stability and strength.

Engineers study these forces to find their size and direction. A common approach is the method of sections. In this method, an imaginary cut is made at a chosen point on the beam, and the forces at that section are analyzed.

One internal force is the normal force, also called the axial force. It acts perpendicular to the beam’s cross-section. Depending on the load, this force can be compressive or tensile.

The other main internal force is the shear force. It acts tangentially, or along the cross-section. Shear forces act in opposite directions on each segment of the beam.

Normal and shear forces can be found by using equilibrium equations on the beam. This analysis is important in structural engineering. It helps engineers judge the stability, strength, and performance of beams and other structural elements.

Beam Loads and Internal Forces

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Beam Forces: Tension, Shear, and Bending

Beam analysis depends on the internal forces and moments inside a structure. These include normal force, shear force, and bending moment. Engineers use the method of sections to cut the beam and find these values. A sign convention helps show whether each result is positive or negative. Normal force acts perpendicular to the beam’s cross-section. It can pull the material in tension or push it in compression. Tension is taken as positive, while compression is taken as negative. This makes it...

normal and shear force

Beam loads create internal forces inside a structure. Weight, pressure, and other external forces can all act on a beam. These internal forces affect the beam’s stability and strength. Engineers study these forces to find their size and direction. A common approach is the method of sections. In this method, an imaginary cut is made at a chosen point on the beam, and the forces at that section are analyzed. One internal force is the normal force, also called the axial force. It acts...

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Beam Internal Force Analysis at Point A

Beam internal force analysis shows how normal force, shear force, and bending moment act inside a structural member. These internal loadings help engineers check whether a beam can support the external forces applied to it. The example uses a beam OC that weighs 5 kN and is inclined at 53.13° with the horizontal. The beam is supported at both ends. The goal is to find the internal loadings at point A. The first step is to find the reaction force at point C. This is done by taking the moment...

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shear diagram

Beam Shear Force Diagram

Beam shear force diagrams show how shear changes along the length of a supported beam. In beam mechanics, they help students track the internal shear force caused by perpendicular loads. The beam AB in this example is supported at both ends, so the first step is to draw a free-body diagram that shows the external forces and internal reactions. The reaction forces at supports A and B are found with equilibrium equations for force and moment. For the beam shown, the vertical reaction at A is 24...

bending moment diagram

Beam Load Analysis with Moment Diagrams

Beam load analysis uses a bending moment diagram to show how bending changes along the length of a beam. This diagram helps engineers and designers check whether a structure can handle applied forces. It is also useful for parts such as shelving arms, which must resist forces and moments from a load. To build the diagram, start by finding the reactive forces and any couple moments on the beam. In some cases, especially when a beam is inclined, these forces must be resolved into components that...

relation between the distributed load and shear

relation-between-the-distributed-load-and-shear

Shear Change Under Distributed Loading

Shear force changes along a beam under a distributed load. In structural analysis, this relationship helps explain how beams respond to loading conditions that also include concentrated loads and a couple moment. To study the link, consider a small beam section that has no concentrated load or couple moment on it. Draw a free-body diagram for that elemental section. It includes the distributed load along the beam, the shear force V(x) on the right-hand side of the cut, and a small added shear...

relation between the shear and bending moment

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Shear and Moment Diagrams in Beam Loads

Shear and moment diagrams help show how a beam responds to loads. A beam can carry a distributed load, concentrated loads, and a couple moment. These loads create internal shear forces and bending moments. The beam is examined by isolating a small elemental section and drawing a free-body diagram. For that section to stay in equilibrium, the moment on the right side must be slightly larger than the moment on the left side. The distributed load also has a resultant force that acts at a...

shear and bending moment diagram: problem solving

shear-and-bending-moment-diagram-problem-solving

Beam Load Analysis with Shear Diagrams

Beam load analysis uses shear and bending moment diagrams to track the internal forces in a beam. These diagrams are important when a beam carries concentrated loads and a distributed load. They help show how the beam responds so structures can be designed safely and efficiently. The first step is to draw a free-body diagram of the whole beam. A free-body diagram shows the concentrated loads, the distributed load, and the reaction forces at the supports. Use the equilibrium equations, where...

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Finding Tension in a Loaded Cable

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Finding Cable Shape Under Distributed Load

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Cable Sag Under Its Own Weight

Overhead power transmission cables sag under their own weight, and that shape affects how they carry electricity across long distances. To study this behavior, the cable is analyzed with a generalized loading function. This function treats the load along the cable's arc length instead of its projected length, which gives a more accurate picture of the cable's response. The analysis then focuses on a small cable segment. A free-body diagram is drawn to show the forces acting on that segment.

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Cable Tension Under Uniform Loading

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key terms and concepts

Learn how beam loads create internal normal and shear forces, and how engineers use the method of sections and equilibrium equations to analyze them.

Beam Loads and Internal Forces | 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

Beam Loads and Internal Forces

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