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

Obciążenie rozłożone to rodzaj obciążenia, które rozkłada się na powierzchni lub konstrukcji.
Weźmy pod uwagę półkę na książki składającą się z książek. Ciężar książek jest równomiernie rozłożony na całej powierzchni.
Nacisk w różnych miejscach na powierzchni odpowiada przyłożonemu obciążeniu na powierzchnię i jest mierzony w niutonach na metr kwadratowy lub paskalach.
Weźmy pod uwagę zaporę hydroelektryczną, w której zanurzona powierzchnia jest modelowana jako prostokątna płyta.
Dla małego elementu o długości dx; siła wywierana na element może być wyrażona jako obciążenie rozłożone dane przez wdx.
Całkując siłę wywieraną na element, określa się całkowite obciążenie, które jest równe wielkości całkowitej powierzchni pod krzywą obciążenia, a jego linia działania przechodzi przez środek ciężkości obszaru.
Punkt, w którym przykładana jest wypadkowa siła, jest znany jako środek nacisku.

<ol>
	<li>Hibbeler, R.C. (2016). Mechanika inżynierska \u2012 Statyka i dynamika. Hoboken, New Jersey: Pearson Prentice Hall. Strona 190</li>
	<li>Piwo, F.P.; Johnston, E.R.; Mazurek, D.F.; Cromwell, PJ i Jaźń, BP (2019). Mechanika wektorowa dla inżynierów \u2012 Statyka i dynamika. Nowy Jork: McGraw-Hill. str. 262.</li>
</ol>

obciążenia rozłożone

Distributed Loads

Obciążenia rozproszone to powszechny rodzaj obciążenia, z którym inżynierowie i naukowcy spotykają się w różnych sytuacjach. Obciążenia rozproszone często odnoszą się do rodzaju obciążenia rozłożonego na powierzchni lub strukturze i mogą być modelowane jako siła ciągła na jednostkę powierzchni.

Na przykład, rozważ półkę na książki wypełnioną pionowo ułożonymi książkami obok siebie. Waga książek jest równomiernie rozłożona na długości półki. W rezultacie, siła przypadająca na każdy odcinek półki odpowiada przyłożonemu obciążeniu i jest mierzona w Newtonach na metr kwadratowy, lub Pascalach.

Jeśli chodzi o inną aplikację, rozważ zaporę wodną, dla której zanurzona powierzchnia jest modelowana jako prostokątna płyta. Siła wywierana na mały element płyty o długości dx może być wyrażona jako obciążenie rozproszone, podane jako wdx, gdzie "w" jest siłą na jednostkę powierzchni. Całkowite obciążenie nałożone na płytę może być określone poprzez zintegrowanie siły działającej na każdy mały element. Wielkość siły wypadkowej wywieranej na płytę jest proporcjonalna do pola powierzchni pod krzywą obciążenia, a jej linia działania przechodzi przez centroid pola. Ten punkt jest znany jako środek ciśnienia. Środek ciśnienia jest istotny przy projektowaniu struktur, które mogą wytrzymać zewnętrzne siły.

Przykładami obciążeń rozproszonych są obciążenia śnieżne na dachu budynku, obciążenia wiatru działające na strukturę, czy nawet waga samochodu na moście.Zrozumienie obciążeń rozłożonych jest kluczowe dla projektowania bezpiecznych i wytrzymałych konstrukcji, które mogą wytrzymać zewnętrzne siły.

Obciążenia rozłożone

Obciążenia rozłożone to powszechny rodzaj obciążenia, z którym inżynierowie i naukowcy spotykają się w różnych sytuacjach praktycznych. Obciążenia rozłożone często odnoszą się do ...

Education

JoVE Core

Mechanical Engineering

Inżynieria mechaniczna

Unit 1

Jednostka 1

Force System Resultants

wypadkowe układu sił

KEY TERMS AND CONCEPTS

Kluczowe terminy i pojęcia

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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principle of moments

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simplification of a force and couple system i

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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...

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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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