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

分布荷重は、サーフェスまたは構造物に分散する荷重の一種です。
本で構成された本棚を考えてみましょう。本の重量は、エリア全体に均等に分散されます。
表面上のさまざまな位置の圧力は、その領域に加えられる荷重に対応し、ニュートン/平方メートルまたはパスカルで測定されます。
水力発電ダムでは、水没したサーフェスが長方形のプレートとしてモデル化されています。
長さ dx の小さな要素の場合、要素に加えられる力は、wdx によって与えられる分布荷重として表すことができます。
要素に加えられる力を積分することにより、荷重曲線の下の総面積に等しい大きさの総荷重が決定され、その作用線は面積の重心を通過します。
合力が加えられる点は、圧力の中心と呼ばれます。

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	<li>ヒベラー、RC(2016)。エンジニアリングメカニクス \u2012 静力学と力学。ニュージャージー州ホーボーケン:ピアソンプレンティスホール。190ページ</li>
	<li>ビール、FP;ジョンストン、ER;マズレック、D.F;クロムウェル、PJおよびセルフ、BP(2019)。エンジニアのためのベクトル力学 \u2012 静力学と動力学。ニューヨーク:マグロウヒル。262ページ。</li>
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分布荷重

Distributed Loads

分布荷重は、エンジニアや科学者がさまざまな実用的な状況で遭遇する一般的な荷重の一種です。分布荷重は、表面または構造物全体に広がる荷重の一種であり、単位面積あたりの連続的な力としてモデル化することができます。

例えば、本が縦に積まれた本棚を考えてみましょう。本の重さは棚の長さ全体に均等に分布しています。その結果、棚の表面の異なる場所における圧力は、適用される荷重に対応し、ニュートン/平方メートルまたはパスカルで測定されます。

別の応用面では、水力発電ダムを考えてみましょう。水中面は長方形の板としてモデル化されます。板の小さな要素にかかる力は、wdxと表される分布荷重として表現できます。ここで、wは単位面積あたりの力です。板にかかる全荷重は、各小要素にかかる力を積分することで求めることができます。板にかかる合力の大きさは、荷重曲線下の面積に比例し、その作用線は面積の重心を通ります。この点を圧力の中心と呼びます。圧力の中心は、外部の力に耐えることができる構造物の設計において重要です。

分布荷重の例には、建物の屋根にかかる雪の荷重、建造物に作用する風の荷重、または橋にかかる車の重さなどがあります。分布荷重を理解することは、外部の力に耐えることができる安全で堅牢な構造物を設計する上で重要です。

分布荷重は、エンジニアや科学者がさまざまな実際の状況で遭遇する一般的なタイプの荷重です。分散負荷は、多くの場合、...

Education

JoVE Core

Mechanical Engineering

機械工学

Unit 1

ユニット1

Force System Resultants

力の系の合力

KEY TERMS AND CONCEPTS

主要用語と概念

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 機械工学は、平衡、力、トラス解析、構造力学などの重要なトピックをカバーする簡潔でわかりやすいアニメーション ビデオを提供します。実際のアプリケーションを探索し、科学者主導の実験を通じてこれらのコンセプトが実際に動作しているのを目撃してください。

mechanical engineering

Load Distribution on Shelves and Dams

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