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

الحمل الموزع هو نوع من الحمل ينتشر على سطح أو هيكل.
ضع في اعتبارك رف كتب يتكون من كتب. يتم توزيع وزن الكتب بالتساوي على المنطقة.
يتوافق الضغط في مواقع مختلفة على السطح مع الحمل المطبق على المنطقة ويتم قياسه بالنيوتن لكل متر مربع أو باسكال.
ضع في اعتبارك سدا لتوليد الطاقة الكهرومائية ، حيث يتم تصميم السطح المغمور على شكل صفيحة مستطيلة.
بالنسبة لعنصر صغير بطول dx ؛ يمكن التعبير عن القوة المؤثرة على العنصر كحمل موزع يعطى بواسطة wdx.
من خلال دمج القوة التي تمارس على العنصر ، يتم تحديد الحمل الكلي ، والذي يساوي في الحجم المساحة الإجمالية تحت منحنى الحمل ، ويمر خط عمله عبر النقطة الوسطى للمنطقة.
تعرف النقطة التي يتم فيها تطبيق القوة الناتجة باسم مركز الضغط.

<ol>
	<li>هيبلر ، آر سي (2016). الميكانيكا الهندسية - الإحصاء والديناميكيات. هوبوكين ، نيو جيرسي: قاعة بيرسون برنتيس. ص 190</li>
	<li>بير ، إف بي ؛ جونستون ، إي آر ؛ مازوريك ، د. إف. كرومويل ، بي جيه وسيلف ، بي بي (2019). ميكانيكا المتجهات للمهندسين - الإحصاء والديناميكيات. نيويورك: ماكجرو هيل. ص 262.</li>
</ol>

الأحمال الموزعة

Distributed Loads

<div style="direction:rtl">الأحمال الموزعة هي نوع شائع من الأحمال التي يتعرض لها المهندسون والعلماء في العديد من التطبيقات العملية. غالبًا ما تشير الأحمال الموزعة إلى حمل ممتد على سطح أو هيكل، ويمكن تمثيلها كقوة مستمرة لكل وحدة مساحة. على سبيل المثال، تخيل رف كتب ممتلئًا بالكتب المكدسة عموديًا بجانب بعضها البعض. يتم توزيع وزن الكتب بشكل متساوٍ على طول الرف. ونتيجة لذلك، فإن الضغط عند المواقع المختلفة على سطح الرف يتناسب مع الحمل المطبق ويُقاس بوحدة نيوتن لكل متر مربع، أو باسكال. في تطبيق آخر، السدود الكهرومائية، حيث يتم نمذجة السطح المغمور على شكل صفيحة مستطيلة. يمكن التعبير عن القوة المؤثرة على عنصر صغير من الصفيحة بطول dx على أنها حمل موزع، يتم التعبير عنه بـ wdx، حيث "w" هو القوة لكل وحدة مساحة. يمكن تحديد الحمل الكلي المطبق على الصفيحة من خلال تكامل القوى المؤثرة على كل عنصر صغير. تعتمد قيمة القوة المحصلة المؤثرة على الصفيحة على مساحة المنطقة تحت منحنى الحمل، وخط تأثيرها يمر عبر مركز المساحة، المعروف باسم مركز الضغط. يُعد مركز الضغط عاملاً أساسيًا في تصميم الهياكل القادرة على تحمل القوى الخارجية، مثل الجدران الحاجزة والسدود. تشمل أمثلة الأحمال الموزعة أحمال الثلوج على أسطح المباني، وأحمال الرياح التي تؤثر على الهياكل، وحتى وزن السيارة على الجسر. يُعد فهم الأحمال الموزعة أمرًا ضروريًا لتصميم هياكل آمنة ومتينة قادرة على تحمل القوى الخارجية.</div>

الأحمال الموزعة هي نوع شائع من الأحمال التي يواجهها المهندسون والعلماء في المواقف العملية المختلفة. غالبا ما تشير الأحمال الموزعة إلى ...

Education

JoVE Core

Mechanical Engineering

الهندسة الميكانيكية

Unit 1

الوحدة الأولى

Force System Resultants

محصلات نظام القوى

KEY TERMS AND CONCEPTS

المصطلحات والمفاهيم الأساسية

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.

mechanical engineering

Load Distribution on Shelves and Dams

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