Name: finding the resultant of distributed loads
Uploaded: 2023-09-22T11:49:32.000Z
Duration: 1 min 13 s
Channel: JoVE

En aplicaciones de ingeniería, es importante tener en cuenta la distribución de la carga a lo largo de la línea.
La fuerza neta aplicada debido a la carga distribuida se representa como un solo vector, llamado fuerza resultante.
Considere una placa plana de forma arbitraria sometida a una carga uniforme.
La fuerza que actúa sobre un área infinitesimal en la placa tiene una magnitud equivalente al elemento de volumen diferencial.
La fuerza resultante que actúa sobre la placa se calcula sumando todas las fuerzas diferenciales que actúan sobre toda la superficie de la placa.
La integración sobre el área de la placa nos da una expresión para calcular la magnitud de la fuerza resultante, que también es igual al volumen total debajo del diagrama de carga distribuida.
La ubicación de la fuerza resultante se determina comparando los momentos de la fuerza resultante con los de todas las fuerzas diferenciales alrededor de sus respectivos ejes.
Las expresiones obtenidas implican que la línea de acción de la fuerza pasa a través del centro geométrico o centroide del volumen bajo el diagrama de carga distribuida.

<ol>
	<li>Hibbeler, R.C. (2016). Ingeniería Mecánica: Estática. Decimocuarta edición, Nueva Jersey: Pearson. Sección 9.4, pág. 511.</li>
	<li>Beer, F.P., Johnston, E.R., Mazurek, D.F., Cornwell, P.J. y Self, B.P. (2016). Mecánica vectorial para ingenieros. Undécima Edición, Nueva York: McGraw-Hill Education. Sección 5.3, pág. 262.</li>
</ol>

resultado de una carga distribuida general

Resultant of a General Distributed Loading

Al diseñar estructuras expuestas a cargas no uniformes, es crucial considerar la fuerza resultante y su ubicación. Esta fuerza resultante es un vector único que representa la fuerza neta aplicada debido a la carga distribuida. Ejemplos como la distribución de carga debido al viento y la distribución de carga en un puente ilustran cómo se utiliza este concepto para analizar y diseñar estructuras seguras y confiables bajo condiciones de carga variables. La mayoría de las estructuras, como edificios residenciales, puentes y torres, están diseñadas para resistir cargas de viento no uniformes, que varían con la velocidad y dirección del viento. De manera similar, los puentes están diseñados para soportar el peso de los vehículos que pasan por ellos. Sin embargo, la distribución del peso de los vehículos no es uniforme y algunas partes del puente pueden experimentar más estrés y tensión que otras. Es necesario calcular la fuerza resultante que actúa sobre los edificios o puentes, lo cual es un problema de distribución de carga no uniforme. Para determinar esta fuerza, es necesario sumar e integrar la magnitud de cada fuerza diferencial que actúa sobre áreas infinitesimales en la superficie portante de carga. La magnitud de esta fuerza resultante es igual al volumen total bajo el diagrama de carga distribuida. La ubicación de esta fuerza resultante se puede determinar comparando sus momentos con los momentos de todas las fuerzas diferenciales alrededor de sus respectivos ejes. Esto implica que la línea de acción de esta fuerza pasará a través del centro geométrico o centroide del volumen en consideración. Saber dónde y cuánta fuerza se aplica a una estructura permite a los ingenieros garantizar la suficiente resistencia y rigidez para que la estructura sea adecuada para su propósito. Estos valores también pueden cambiar según las condiciones variables de carga, por lo que es esencial considerar estos posibles cambios para diseñar una estructura segura y segura.

Resultado de una carga distribuida general

Al diseñar estructuras expuestas a cargas no uniformes, es crucial tener en cuenta la fuerza resultante y su ubicación. Esta fuerza resultante es una sola fuerza ...

resultant-of-a-general-distributed-loading

Education

Educación

JoVE Core

Mechanical Engineering

Ingeniería Mecánica

Unit 1

Unidad 1

Center of Gravity and Centroid

Centro de gravedad y centroide

KEY TERMS AND CONCEPTS

TÉRMINOS Y CONCEPTOS CLAVE

finding the resultant of distributed loads

Distributed loads create a force that is spread over a surface instead of acting at one point. To analyze this kind of loading, engineers use a single resultant force. That force represents the net effect of the entire load.

This idea is important in structures that face non-uniform loads. Wind can push on buildings and towers with changing speed and direction, so the load is not evenly spread. Bridges also experience non-uniform loading from vehicles, and some parts of the bridge can feel more stress and strain than others.

To find the resultant force, the small forces acting on tiny areas are added together with integration over the load-bearing surface. The size of the resultant force equals the total area under the distributed-loading diagram. Its location is found by comparing moments, which means the turning effects of the force about an axis.

The line of action of the resultant passes through the geometric center, or centroid, of the volume under the load diagram. Knowing both the size and location of the force helps engineers judge whether a structure has enough strength and rigidity. Because loading can change, these calculations help support safe and reliable design for buildings, bridges, and other structures.

Finding the Resultant of Distributed Loads

finding-the-resultant-of-distributed-loads

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resultant of a general distributed loading

Distributed loads create a force that is spread over a surface instead of acting at one point. To analyze this kind of loading, engineers use a single resultant force. That force represents the net effect of the entire load. This idea is important in structures that face non-uniform loads. Wind can push on buildings and towers with changing speed and direction, so the load is not evenly spread. Bridges also experience non-uniform loading from vehicles, and some parts of the bridge can feel...

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key terms and concepts

Learn how engineers combine non-uniform loads into one resultant force, find its location with moments, and apply the idea to bridges and buildings.

Finding the Resultant of Distributed Loads | JoVE K12

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mechanical engineering

Finding the Resultant of Distributed Loads

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