Name: load distribution on shelves and dams
Uploaded: 2023-09-22T11:49:22.000Z
Duration: 1 min 19 s
Channel: JoVE

Una carga distribuida es un tipo de carga que se extiende sobre una superficie o una estructura.
Considera una estantería que consta de libros. El peso de los libros se distribuye uniformemente sobre el área.
La presión en diferentes lugares de la superficie corresponde a la carga aplicada sobre el área y se mide en Newton por metro cuadrado o pascales.
Pensemos en una presa hidroeléctrica, en la que la superficie sumergida se modela como una placa rectangular.
Para un elemento pequeño de longitud dx, la fuerza ejercida sobre el elemento se puede expresar como una carga distribuida dada por wdx.
Al integrar la fuerza ejercida sobre el elemento, se determina la carga total, que es igual en magnitud al área total bajo la curva de carga, y su línea de acción pasa por el centroide del área.
El punto donde se aplica la fuerza resultante se conoce como centro de presión.

<ol>
	<li>Hibbeler, R.C. (2016). Ingeniería Mecánica \u2012 Estática y Dinámica. Hoboken, Nueva Jersey: Pearson Prentice Hall. págs. 190</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. 262.</li>
</ol>

cargas distribuidas

Distributed Loads

Las cargas distribuidas son un tipo común de carga que los ingenieros y científicos encuentran en diversas situaciones prácticas. Las cargas distribuidas se refieren a menudo a un tipo de carga repartida sobre una superficie o una estructura, y pueden ser modeladas como una fuerza continua por unidad de área. Por ejemplo, consideremos una estantería llena de libros apilados verticalmente uno al lado del otro. El peso de los libros se distribuye uniformemente a lo largo de la longitud de la estantería. Como resultado, la presión en diferentes puntos de la superficie de la estantería corresponde a la carga aplicada y se mide en Newtons por metro cuadrado, o Pascales. En cuanto a otra aplicación, consideremos una presa hidroeléctrica, para la cual la superficie sumergida se modela como una placa rectangular. La fuerza ejercida sobre un pequeño elemento de la placa de longitud dx puede expresarse como la carga distribuida, dada por wdx, donde "w" es la fuerza por unidad de área. La carga total aplicada a la placa puede determinarse integrando la fuerza ejercida sobre cada pequeño elemento. La magnitud de la fuerza resultante ejercida sobre la placa es proporcional al área bajo la curva de carga, y su línea de acción pasa a través del centroide del área. Este punto se conoce como el centro de presión. El centro de presión es esencial para diseñar estructuras que puedan resistir fuerzas externas. Ejemplos de cargas distribuidas incluyen cargas de nieve en el techo de un edificio, cargas de viento que actúan sobre una estructura o incluso el peso de un automóvil sobre un puente. Comprender las cargas distribuidas es crucial para diseñar estructuras seguras y robustas que puedan resistir fuerzas externas.

Cargas distribuidas

Las cargas distribuidas son un tipo común de carga que los ingenieros y científicos encuentran en diversas situaciones prácticas. Las cargas distribuidas a menudo se refieren a un ...

Education

Educación

JoVE Core

Mechanical Engineering

Ingeniería Mecánica

Unit 1

Unidad 1

Force System Resultants

Resultantes de Sistemas de Fuerzas

KEY TERMS AND CONCEPTS

TÉRMINOS Y CONCEPTOS CLAVE

load distribution on shelves and dams

Load distribution helps engineers describe how force spreads across a surface or structure. A distributed load is a continuous force per unit area, rather than a single point force. It is a common idea in many practical situations.

A bookshelf full of stacked books is one simple example. The weight of the books is spread along the shelf, so the pressure changes across the surface. This pressure is measured in Newtons per square meter, or Pascals.

A hydroelectric dam gives another clear example. The submerged surface can be modeled as a rectangular plate. The force on a small piece of that plate, with length dx, is written as wdx, where w is the force per unit area.

The total load on the plate is found by integrating the force from each small element. The size of the resultant force is related to the area under the load curve. Its line of action passes through the centroid of that area. This point is called the center of pressure, and it is important for designing structures that can resist external forces.

Distributed loads also appear in many other situations. Snow on a roof, wind on a structure, and the weight of a car on a bridge are all examples. Understanding these loads helps engineers build safe and robust structures.

Load Distribution on Shelves and Dams

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key terms and concepts

Learn how distributed loads spread force across shelves, dams, roofs, and bridges, and how engineers use integration and the center of pressure to design safe structures.

Load Distribution on Shelves and Dams | 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

Load Distribution on Shelves and Dams

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