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

Un carico distribuito è un tipo di carico distribuito su una superficie o una struttura.
Considera una libreria composta da libri. Il peso dei libri è distribuito uniformemente sull'area.
La pressione in diversi punti della superficie corrisponde al carico applicato sull'area ed è misurata in Newton per metro quadrato o Pascal.
Si consideri una diga idroelettrica, in cui la superficie sommersa è modellata come una piastra rettangolare.
Per un piccolo elemento di lunghezza dx, la forza esercitata sull'elemento può essere espressa come un carico distribuito dato da wdx.
Integrando la forza esercitata sull'elemento, si determina il carico totale, che è uguale in grandezza all'area totale sotto la curva di carico, e la sua linea d'azione passa attraverso il baricentro dell'area.
Il punto in cui viene applicata la forza risultante è noto come centro di pressione.

<ol>
	<li>Hibbeler, R.C. (2016). Ingegneria Meccanica \u2012 Statica e Dinamica. Hoboken, New Jersey: Pearson Prentice Hall. pagine 190</li>
	<li>Birra, F.P.; Johnston, E.R.; Mazurek, D.F; Cromwell, P.J. e Self, B.P.(2019). Meccanica vettoriale per ingegneri \u2012 Statica e dinamica. New York: McGraw-Hill. 262.</li>
</ol>

carichi distribuiti

Distributed Loads

I carichi distribuiti sono un tipo comune di carico che ingegneri e scienziati incontrano in varie situazioni pratiche. Questi si riferiscono spesso a un tipo di carico disposto su una superficie o una struttura e possono essere modellati come una forza continua per unità di area.

Ad esempio, consideriamo una libreria piena di libri impilati verticalmente uno accanto all'altro. Il peso dei libri è distribuito in modo uniforme lungo la lunghezza della mensola. Di conseguenza, la pressione in diverse posizioni sulla superficie della mensola corrisponde al carico applicato e viene misurata in Newton per metro quadrato, o Pascal.

In termini di un'altra applicazione, consideriamo una diga idroelettrica, per la quale la superficie sommersa è modellata come una piastra rettangolare. La forza esercitata su un piccolo elemento della piastra di lunghezza dx può essere espressa come il carico distribuito, dato da wdx, dove "w" è la forza per unità di area. Il carico totale applicato alla piastra può essere determinato integrando la forza esercitata su ciascun piccolo elemento. La magnitudine della forza risultante esercitata sulla piastra è proporzionale all'area sotto la curva del carico e la sua linea d'azione passa attraverso il baricentro dell'area. Questo punto è conosciuto come il centro di pressione. Il centro di pressione è essenziale nel progettare strutture che possano resistere alle forze esterne.

Esempi di carichi distribuiti includono carichi di neve sul tetto di un edificio, carichi di vento che agiscono su una struttura o persino il peso di una macchina su un ponte. Comprendere i carichi distribuiti è cruciale per progettare strutture sicure e robuste che in grado di resistere alle forze esterne.

Carichi distribuiti

I carichi distribuiti sono un tipo comune di carico che ingegneri e scienziati incontrano in varie situazioni pratiche. I carichi distribuiti si riferiscono spesso a un ...

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JoVE Core

Mechanical Engineering

Ingegneria Meccanica

Unit 1

Unità 1

Force System Resultants

Risultanti dei sistemi di forze

KEY TERMS AND CONCEPTS

TERMINI E CONCETTI CHIAVE

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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