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

Распределенная нагрузка — это тип нагрузки, которая распределяется по поверхности или конструкции.
Рассмотрим книжную полку, состоящую из книг. Вес книг равномерно распределяется по площади.
Давление в разных местах на поверхности соответствует приложенной нагрузке на площадь и измеряется в ньютонах на квадратный метр или Паскалях.
Рассмотрим плотину гидроэлектростанции, где погруженная поверхность моделируется в виде прямоугольной пластины.
Для небольшого элемента длины dx сила, действующая на элемент, может быть выражена как распределенная нагрузка, заданная wdx.
Путем интегрирования силы, действующей на элемент, определяется общая нагрузка, которая по величине равна общей площади под кривой нагрузки, и ее линия действия проходит через центроид площади.
Точка, в которой приложена результирующая сила, известна как центр давления.

<ol>
	<li>Хиббелер, Р.К. (2016). Инженерная механика \u2012 Статика и динамика. Хобокен, Нью-Джерси: Пирсон Прентис Холл. С. 190</li>
	<li>Бир, Ф..; Джонстон, Э.Р.; Мазурек, Д.Ф; Кромвель,.Д. и Селф, Б.. (2019). Векторная механика для инженеров \u2012 Статика и динамика. Нью-Йорк: Макгроу-Хилл. С. 262.</li>
</ol>

Распределенные нагрузки

Distributed Loads

Распределенные нагрузки являются обычным типом нагрузки, с которыми сталкиваются инженеры и ученые в различных практических ситуациях. Распределенные нагрузки часто относятся к типу нагрузки, распределенной на поверхности или конструкции и могут быть моделированы как непрерывное воздействие на единицу площади.

Например, рассмотрите книжную полку, заполненную вертикально стоящими книгами, расположенными рядом друг с другом. Вес книг равномерно распределен по длине полки. В результате давление в разных местах на поверхности полки соответствует приложенной нагрузке и измеряется в ньютонах на квадратный метр, или паскалях.

В терминах другого применения, рассмотрим гидроэлектрическую плотину, для которой погруженная поверхность моделируется как прямоугольная пластина. Сила, действующая на малый элемент пластины длиной dx, может быть выражена как распределенная нагрузка, заданная wdx, где "w"  - это сила на единицу площади. Общая нагрузка, приложенная к пластине, может быть определена путем интегрирования силы, действующей на каждый маленький элемент. Величина результирующей силы, действующей на пластину, пропорциональна площади под кривой нагрузки, а линия действия проходит через центроид площади. Эта точка известна как центр давления. Центр давления является важным при проектировании конструкций, которые могут выдерживать внешние силы.

Примеры распределенных нагрузок включают снеговую нагрузку на крыше здания, ветровую нагрузку на конструкцию или даже вес машины на мосту. Понимание распределенных нагрузок важно для проектирования безопасных и прочных конструкций, способных выдерживать внешние силы.

Распределенные нагрузки — это распространенный тип нагрузки, с которым инженеры и ученые сталкиваются в различных практических ситуациях. Распределенные нагрузки часто относятся к ...

Education

JoVE Core

Mechanical Engineering

Машиностроение

Unit 1

Раздел 1

Force System Resultants

Результирующие силы системы

KEY TERMS AND CONCEPTS

ОСНОВНЫЕ ТЕРМИНЫ И ПОНЯТИЯ

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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Resolving Forces in Moment Calculations

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Torque About an Axis in 3D Systems

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Equivalent Force and Moment Systems

Structural systems often experience several forces and couple moments at the same time. Engineers simplify these loading cases by replacing them with an equivalent force and moment system at a chosen point O. This makes the analysis easier while keeping the same external effects on the member. A key idea in this process is the principle of transmissibility. A force is a sliding vector, which means it can be moved anywhere along its line of action without changing how the body behaves...

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Resultant Forces in Force and Couple Systems

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distributed loads

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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Equivalent Resultant Loads on Beams

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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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