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

Uma carga distribuída é um tipo de carga que é espalhada sobre uma superfície ou estrutura.
Considere uma estante composta por livros. O peso dos livros é distribuído uniformemente pela área.
A pressão em diferentes locais da superfície corresponde à carga aplicada sobre a área e é medida em Newton por metro quadrado ou Pascals.
Considere uma barragem hidrelétrica, onde a superfície submersa é modelada como uma placa retangular.
Para um pequeno elemento de comprimento dx; a força exercida sobre o elemento pode ser expressa como uma carga distribuída dada por wdx.
Ao integrar a força exercida sobre o elemento, determina-se a carga total, que é igual em magnitude à área total sob a curva de carga, e sua linha de ação passa pelo centróide da área.
O ponto onde a força resultante é aplicada é conhecido como centro de pressão.

<ol>
	<li>Hibbeler, R.C. (2016). Engenharia Mecânica \u2012 Estática e Dinâmica. Hoboken, Nova Jersey: Pearson Prentice Hall. pág. 190</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. 262.</li>
</ol>

cargas distribuídas

Distributed Loads

Cargas distribuídas são um tipo comum de carga que engenheiros e cientistas encontram em várias situações práticas. Cargas distribuídas frequentemente se referem a um tipo de carga espalhada sobre uma superfície ou uma estrutura e podem ser modeladas como uma força contínua por unidade de área.

Por exemplo, considere uma estante cheia de livros empilhados verticalmente um ao lado do outro. O peso dos livros é distribuído de forma uniforme ao longo do comprimento da estante. Como resultado, a pressão em diferentes locais na superfície da estante corresponde à carga aplicada e é medida em Newtons por metro quadrado, ou Pascals.

Em termos de outra aplicação, considere uma represa hidroelétrica, para a qual a superfície submersa é modelada como uma placa retangular. A força exercida sobre um pequeno elemento da placa de comprimento dx pode ser expressa como a carga distribuída, dada por wdx, onde "w" é a força por unidade de área. A carga total aplicada na placa pode ser determinada integrando a força exercida sobre cada pequeno elemento. A magnitude da força resultante exercida na placa é proporcional à área sob a curva de carga, e sua linha de ação passa pelo centroide da área. Esse ponto é conhecido como centro de pressão. O centro de pressão é essencial na concepção de estruturas capazes de suportar forças externas.

Exemplos de cargas distribuídas incluem cargas de neve no telhado de um edifício, cargas de vento atuando em uma estrutura ou até mesmo o peso de um carro em uma ponte. Compreender as cargas distribuídas é crucial para projetar estruturas seguras e robustas que possam suportar forças externas.

Cargas Distribuídas

Cargas distribuídas são um tipo comum de carga que engenheiros e cientistas encontram em várias situações práticas. Cargas distribuídas geralmente se referem a um ...

Education

JoVE Core

Mechanical Engineering

Engenharia Mecânica

Unit 1

Unidade 1

Force System Resultants

Resultantes de Sistemas de Forças

KEY TERMS AND CONCEPTS

TERMOS-CHAVE E CONCEITOS

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

O JoVE Core Mechanical Engineering oferece vídeos animados concisos e de fácil compreensão que abrangem tópicos-chave como equilíbrio, forças, análise de treliças e mecânica estrutural. Explore suas aplicações no mundo real e observe esses conceitos em ação por meio de experimentos conduzidos por cientistas.

mechanical engineering

Load Distribution on Shelves and Dams

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