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

O diagrama de cisalhamento é uma representação gráfica da distribuição das forças de cisalhamento ao longo do comprimento da viga.
Considere uma viga AB apoiada em duas extremidades e sujeita a cargas perpendiculares. Construa seu diagrama de cisalhamento.
Desenhe o diagrama de corpo livre da viga. Usando as equações de equilíbrio de força e momento, as forças de reação em cada suporte podem ser calculadas.
Aplique o método de corte à viga.
Em seguida, considere uma distância arbitrária do ponto A dentro da região AP. Desenhe um diagrama de corpo livre da seção. Sob a condição de equilíbrio, a força de cisalhamento na seção é igual à força de reação no suporte.
Da mesma forma, considere um ponto arbitrário dentro da região PQ. Desenhando o diagrama de corpo livre e usando a equação de equilíbrio, o cisalhamento na seção pode ser determinado.
Finalmente, o ponto arbitrário é considerado na seção QB. Ao desenhar o diagrama de corpo livre e recordar a equação de equilíbrio, o cisalhamento na seção pode ser determinado, que permanece constante até o final da viga e, finalmente, vai a zero para manter o equilíbrio.

<ol>
	<li>Hibbeler, R.C. (2016). Engenharia Mecânica \u2012 Estática e Dinâmica. Hoboken, Nova Jersey: Pearson Prentice Hall. pág. 361.</li>
	<li>Cerveja, F.P.; Johnston, E.R.; Mazurek, D.F; Cromwell, PJ e Self, BP (2019). Mecânica vetorial para engenheiros \u2012 estática e dinâmica. Nova Iorque: McGraw-Hill. Pág. 381.</li>
</ol>

diagrama de cisalhamento

No estudo de mecânica de vigas, os diagramas de cisalhamento desempenham um papel crucial na compreensão da distribuição das forças de cisalhamento ao longo do comprimento de uma viga. Considere uma viga AB que é suportada em ambas as extremidades e submetida a cargas perpendiculares.

Primeiro, um diagrama de corpo livre da viga é desenhado, representando todas as forças externas e reações internas atuantes na viga. As forças de reação em cada suporte podem ser calculadas utilizando as equações de equilíbrio de força e momento. A componente vertical das forças de reação nos pontos A e B obtidas para a viga dada é de 24 kN e 18 kN, respectivamente.

<img alt="Figure 1" src="/files/ftp_upload/14301/14301_PT_Figure_1v2.svg" style="text-align: center; height: 300px;" />

Um diagrama de cisalhamento é uma representação gráfica que ilustra a distribuição das forças de cisalhamento ao longo do comprimento da viga. Para criar esse diagrama, o método das seções é aplicado à viga. Em seguida, uma distância arbitrária a partir do ponto A dentro da região AP é considerada. Um diagrama de corpo livre desta seção é desenhado para analisar as forças atuantes sobre ela. Sob a condição de equilíbrio, a força de cisalhamento na seção é igual à força de reação no suporte, que é V1 = 24 kN.

Da mesma forma, um ponto arbitrário dentro da região PQ é considerado. Ao desenhar um diagrama de corpo livre dessa seção e usar a equação de equilíbrio, a força de cisalhamento V2 pode ser determinada.

<img alt="Equation 1" src="/files/ftp_upload/14301/14301_Equation_1v2.svg" style="text-align: center; height: 13px;" />

Por fim, um ponto arbitrário é considerado dentro da seção QB. Um diagrama de corpo livre é desenhado para essa seção, e a equação de equilíbrio é aplicada para determinar a força de cisalhamento V3 na seção.

<img alt="Equation 2" src="/files/ftp_upload/14301/14301_Equation_2v2.svg" style="text-align: center; height: 13px;" />

Essa força de cisalhamento permanece constante até o final da viga, chegando eventualmente a zero para manter o equilíbrio.

Diagrama de cisalhamento

No estudo da mecânica das vigas, os diagramas de cisalhamento desempenham um papel crucial na compreensão da distribuição das forças de cisalhamento ao longo do comprimento de uma viga. Considerar...

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KEY TERMS AND CONCEPTS

TERMOS-CHAVE E CONCEITOS

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 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.

Beam Shear Force Diagram

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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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