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

Nelle applicazioni ingegneristiche, è importante considerare la distribuzione del carico lungo la linea.
La forza netta applicata a causa del carico distribuito è rappresentata come un singolo vettore, chiamato forza risultante.
Si consideri una piastra piana di forma arbitraria soggetta a un carico uniforme.
La forza che agisce su un'area infinitesimale della piastra ha una grandezza equivalente all'elemento di volume differenziale.
La forza risultante che agisce sulla piastra viene calcolata sommando tutte le forze differenziali che agiscono sull'intera superficie della piastra.
L'integrazione sull'area della piastra ci fornisce un'espressione per calcolare l'entità della forza risultante, che è anche uguale al volume totale sotto il diagramma di carico distribuito.
La posizione della forza risultante è determinata confrontando i momenti della forza risultante con quelli di tutte le forze differenziali attorno ai rispettivi assi.
Le espressioni ottenute implicano che la linea d'azione della forza passa attraverso il centro geometrico o baricentro del volume sotto il diagramma di carico distribuito.

<ol>
	<li>Hibbeler, R.C. (2016). Ingegneria Meccanica: Statica. Quattordicesima edizione, New Jersey: Pearson. Sezione 9.4, pp. 511.</li>
	<li>Birra, F.P., Johnston, E.R., Mazurek, D.F., Cornwell, P.J. e Self, B.P. (2016). Meccanica vettoriale per ingegneri. Undicesima edizione, New York: McGraw-Hill Education. Sezione 5.3, pp. 262.</li>
</ol>

risultante di un carico distribuito generale

Resultant of a General Distributed Loading

Nel progettare strutture esposte a carichi non uniformi, è fondamentale considerare la forza risultante e la sua posizione. Questa forza risultante è un vettore singolo che rappresenta la forza netta applicata a causa del carico distribuito.
Esempi come la distribuzione del carico a causa del vento e la distribuzione del carico su un ponte, illustrano come questo concetto venga utilizzato per analizzare e progettare strutture sicure ed affidabili in condizioni di carico variabile. La maggior parte delle strutture, come edifici residenziali, ponti e torri, sono progettate per resistere al carico non uniforme del vento, che varia con la velocità e la direzione del vento. Allo stesso modo, i ponti sono progettati per resistere al peso dei veicoli che li attraversano. Tuttavia, la distribuzione del peso dei veicoli non è uniforme, e alcune parti del ponte possono subire più stress e tensione rispetto ad altre. È necessario calcolare la forza risultante che agisce sugli edifici o sui ponti, che costituisisce un problema di distribuzione di carico non uniforme.

Per determinare questa forza, è necessario sommare e integrare la magnitudine di ciascuna forza differenziale che agisce su aree infinitamente piccole sopra l'area portante del carico. La magnitudine di questa forza risultante è uguale al volume totale sotto il diagramma di carico distribuito. La posizione di questa forza risultante può essere determinata confrontando i suoi momenti con i momenti di tutte le forze differenziali rispetto ai loro rispettivi assi. Ciò implica che la linea d'azione di questa forza passerà attraverso il centro geometrico o il baricentro del volume preso in considerazione.

Sapere dove e quanto viene applicata una forza ad una struttura consente agli ingegneri di garantire una sufficiente resistenza e rigidità affinché la struttura sia adatta allo scopo. Questi valori potrebbero anche cambiare in base a condizioni di carico variabili, quindi è essenziale considerare questi cambiamenti potenziali al fine di progettare una struttura sicura e protetta.

Risultante di un Carico Distribuito Generale

Durante la progettazione di strutture esposte a carichi non uniformi, è fondamentale considerare la forza risultante e la sua posizione. Questa forza risultante è un singolo ...

resultant-of-a-general-distributed-loading

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Mechanical Engineering

Ingegneria Meccanica

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Center of Gravity and Centroid

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KEY TERMS AND CONCEPTS

TERMINI E CONCETTI CHIAVE

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

center of gravity

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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

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.

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Finding the Resultant of Distributed Loads

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