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

Eine verteilte Last ist eine Art von Last, die über eine Fläche oder ein Bauwerk verteilt ist.
Stellen Sie sich ein Bücherregal vor, das aus Büchern besteht. Das Gewicht der Bücher wird gleichmäßig über die Fläche verteilt.
Der Druck an verschiedenen Stellen auf der Oberfläche entspricht der über die Fläche ausgeübten Last und wird in Newton pro Quadratmeter oder Pascal gemessen.
Stellen Sie sich einen Wasserkraftwerksdamm vor, bei dem die Unterwasseroberfläche als rechteckige Platte modelliert ist.
Für ein kleines Element der Länge dx kann die auf das Element ausgeübte Kraft als verteilte Last ausgedrückt werden, die durch wdx gegeben ist.
Durch die Integration der auf das Element ausgeübten Kraft wird die Gesamtlast bestimmt, die in ihrer Größe der Gesamtfläche unter der Lastkurve entspricht, und ihre Wirkungslinie verläuft durch den Schwerpunkt der Fläche.
Der Punkt, an dem die resultierende Kraft aufgebracht wird, wird als Druckzentrum bezeichnet.

<ol>
	<li>Hibbeler, R.C. (2016). Technische Mechanik \u2012 Statik und Dynamik. Hoboken, New Jersey: Pearson Prentice Hall. Seite 190</li>
	<li>Bier, F.P.; Johnston, E.R.; Mazurek, D.F.; Cromwell, P.J. und Self, B.P.(2019). Vektormechanik für Ingenieure \u2012 Statik und Dynamik. New York: McGraw-Hill. Seite 262.</li>
</ol>

verteilte lasten

Distributed Loads

Verteilte Lasten sind eine häufige Art von Belastung, mit der Ingenieure und Wissenschaftler in verschiedenen praktischen Situationen konfrontiert werden. Verteilte Lasten beziehen sich oft auf eine Art Belastung, die sich über eine Oberfläche oder eine Struktur erstreckt und als kontinuierliche Kraft pro Flächeneinheit modelliert werden kann. Zum Beispiel betrachten Sie ein Bücherregal, das mit vertikal übereinander gestapelten Büchern gefüllt ist. Das Gewicht der Bücher ist gleichmäßig über die Länge des Regals verteilt. Dadurch entspricht der Druck an verschiedenen Stellen auf der Oberfläche des Regals der aufgebrachten Last und wird in Newton pro Quadratmeter oder Pascal gemessen. Im Hinblick auf eine andere Anwendung betrachten Sie eine Wasserkraftanlage, bei der die untergetauchte Oberfläche als rechteckige Platte modelliert wird. Die auf ein kleines Element der Platte von der Länge dx ausgeübte Kraft kann als die verteilte Last ausgedrückt werden, gegeben durch wdx, wobei "w" die Kraft pro Flächeneinheit ist. Die Gesamtlast, die auf die Platte aufgebracht wird, kann durch Integration der auf jedes kleine Element ausgeübten Kraft bestimmt werden. Die Größe der resultierenden auf die Platte ausgeübten Kraft ist proportional zur Fläche unter der Lastkurve, und ihre Wirkungslinie verläuft durch den Schwerpunkt der Fläche. Dieser Punkt wird als Druckmittelpunkt bezeichnet. Der Druckmittelpunkt ist für das Entwerfen von Strukturen, die äußeren Kräften standhalten können, unerlässlich. Beispiele für verteilte Lasten sind Schneelasten auf dem Dach eines Gebäudes, Windlasten auf einer Struktur oder auch das Gewicht eines Autos auf einer Brücke. Das Verständnis verteilter Lasten ist entscheidend für das Entwerfen sicherer, robuster Strukturen, die äußeren Kräften standhalten können.

Verteilte Lasten

Verteilte Lasten sind eine häufige Art von Last, auf die Ingenieure und Wissenschaftler in verschiedenen praktischen Situationen stoßen. Verteilte Lasten beziehen sich oft auf eine ...

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JoVE Core

Mechanical Engineering

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Unit 1

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Force System Resultants

Resultierende eines Kraftsystems

KEY TERMS AND CONCEPTS

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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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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.

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Load Distribution on Shelves and Dams

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