Name: beam shear force diagram
Uploaded: 2025-05-22T09:06:03.000Z
Duration: 1 min 27 s
Channel: JoVE

El diagrama de cortante es una representación gráfica de la distribución de los esfuerzos cortantes a lo largo de la longitud de la viga.
Considere una viga AB apoyada en dos extremos y sometida a cargas perpendiculares. Construya su diagrama de corte.
Dibuja el diagrama de cuerpo libre de la viga. Usando las ecuaciones de equilibrio de fuerza y momento, se pueden calcular las fuerzas de reacción en cada soporte.
Aplique el método de sección a la viga.
A continuación, considere una distancia arbitraria desde el punto A dentro de la región AP. Dibuje un diagrama de cuerpo libre de la sección. En la condición de equilibrio, la fuerza cortante en la sección es igual a la fuerza de reacción en el soporte.
Del mismo modo, considere un punto arbitrario dentro de la región PQ. Al dibujar el diagrama de cuerpo libre y usar la ecuación de equilibrio, se puede determinar el corte en la sección.
Finalmente, el punto arbitrario se considera dentro de la sección QB. Al dibujar el diagrama de cuerpo libre y recordar la ecuación de equilibrio, se puede determinar el corte en la sección, que permanece constante hasta el final de la viga y finalmente llega a cero para mantener el equilibrio.

<ol>
	<li>Hibbeler, R.C. (2016). Ingeniería Mecánica \u2012 Estática y Dinámica. Hoboken, Nueva Jersey: Pearson Prentice Hall. págs. 361.</li>
	<li>Cerveza, F.P.; Johnston, E.R.; Mazurek, D.F.; Cromwell, P.J. y Self, B.P. (2019). Mecánica vectorial para ingenieros: estática y dinámica. Nueva York: McGraw-Hill. Págs. 381.</li>
</ol>

diagrama de cortante

En el estudio de la mecánica de vigas, los diagramas de cortante juegan un papel crucial para entender la distribución de las fuerzas cortantes a lo largo de la longitud de la viga. Consideremos una viga AB que está soportada en ambos extremos y está sometida a cargas perpendiculares.

 Primero, se dibuja un diagrama de cuerpo libre de la viga, representando todas las fuerzas externas y reacciones internas que actúan sobre la viga. Uno puede calcular las fuerzas de reacción en cada soporte empleando las ecuaciones de equilibrio de fuerza y momento. La componente vertical de las fuerzas de reacción en los puntos A y B obtenidas para la viga dada es de 24 kN y 18 kN, respectivamente.

 <img alt="Figure 1" src="/files/ftp_upload/14301/14301_PT_Figure_1v2.svg" style="text-align: center; height: 300px;">

 Un diagrama de cortante es una representación gráfica que ilustra la distribución de las fuerzas cortantes a lo largo de la longitud de la viga. Para crear este diagrama, se aplica el método de secciones a la viga. A continuación, se considera una distancia arbitraria desde el punto A dentro de la región AP. Se dibuja un diagrama de cuerpo libre de esta sección para analizar las fuerzas que actúan sobre ella. Bajo la condición de equilibrio, la fuerza cortante en la sección es igual a la fuerza de reacción en el soporte, que es V1 = 24 kN.

 De manera similar, se considera un punto arbitrario dentro de la región PQ. Al dibujar un diagrama de cuerpo libre de esta sección y utilizar la ecuación de equilibrio, se puede determinar la fuerza cortante V2. 

<img alt="Equation 1" src="/files/ftp_upload/14301/14301_Equation_1v2.svg" style="text-align: center; height: 13px;"> 

Finalmente, se considera un punto arbitrario dentro de la sección QB. Se dibuja un diagrama de cuerpo libre para esta sección y se aplica la ecuación de equilibrio para determinar la fuerza cortante V3 en la sección. <img alt="Equation 2" src="/files/ftp_upload/14301/14301_Equation_2v2.svg" style="text-align: center; height: 13px;"> Esta fuerza cortante permanece constante hasta el final de la viga, llegando finalmente a cero para mantener el equilibrio.

Diagrama de cortante

En el estudio de la mecánica de vigas, los diagramas de corte juegan un papel crucial en la comprensión de la distribución de las fuerzas de corte a lo largo de la longitud de una viga. Considerar...

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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 kN and the vertical reaction at B is 18 kN. These values become the starting point for building the shear diagram.

To form the shear diagram, the method of sections is used. A point is chosen at an arbitrary distance from A in the region AP, and a free-body diagram of that section is drawn. From equilibrium, the shear force in that section is V1 = 24 kN.

The same process is repeated in the region PQ. An arbitrary point is selected, the section is isolated, and the equilibrium equation is applied to find V2. A third section is then taken in the region QB. Its free-body diagram gives V3, which stays constant until the end of the beam and then goes to zero so the beam remains in equilibrium.

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Learn how to build a beam shear force diagram using free-body diagrams, reaction forces, and the method of sections for a supported beam.

Beam Shear Force Diagram | JoVE K12

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Beam Shear Force Diagram

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