Name: equivalent resultant loads on beams
Uploaded: 2023-09-22T11:49:23.000Z
Duration: 1 min 21 s
Channel: JoVE

ضع في اعتبارك شعاع مدبب OB مثبت في أحد طرفيه ويخضع لحمل موزع.
حدد القوة الناتجة المكافئة للحمل المتغير وحدد موقعها على الحزمة.
أولا ، قسم الحمل الموزع إلى منطقتين مثلثتين.
بعد ذلك ، حجم الحمل الناتج المكافئ للمنطقة المثلثة اليمنى واليسرى يساوي مساحة كل مثلث.
يعمل كل حمل ناتج عند الوسطيات الوسطى ، وتقع عند ثلث طول القاعدة من الجانب الرأسي AD للمثلث.
يمكن تحديد الحمل الناتج المكافئ عن طريق إضافة الحمل الناتج الفردي لكل منطقة مثلثة.
يمكن تحديد اللحظة حول النقطة O عن طريق إضافة اللحظة الفردية التي تعمل بسبب كل حمل ناتج.
تذكر مبدأ العزم ، الذي ينص على أن لحظة الحمل الناتج المكافئ حول النقطة O تساوي حاصل ضرب الحمل الناتج المكافئ والمسافة من النقطة O.
من خلال استبدال القيم في المعادلة ، يمكن تحديد موقع الحمل الناتج المكافئ.

<ol>
	<li>هيبلر ، آر سي (2016). الميكانيكا الهندسية - الإحصاء والديناميكيات. هوبوكين ، نيو جيرسي: بيرسون برنتيس هول ، ص 194-195</li>
</ol>

الأحمال الموزعة: حل المشكلات

<div style="direction:rtl">تعتبر الكَمَرَة أجزاء هيكلية شائعة تستخدم بشكل متكرر في التطبيقات الهندسية التي تتطلب قدرات مختلفة لحمل الأحمال. يكمن الخطوة الأولى في تحليل الجائز تحت حمل موزع في تبسيط المشكلة عند تقسيم الحمل إلى مناطق أصغر، وهذا يسمح للشخص بالنظر إلى كل منطقة على حدة وحساب قيمة التحميل المكافئ المحصل على كل جزء من الحاملة. يمكن تحديد حجم الحمل المكافئ الناتج لكل منطقة عن طريق حساب مساحة المناطق المعنية، والتي تمثل القوة المتحملة بواسطة الحمل في كل منطقة. بعد ذلك، يتعين تحديد موقع كل حمولة ناتجة على الكَمَرَة. يمكن القيام بذلك عن طريق العثور على مراكز الأثقال في المناطق، والتي تعتبر نقاط حيث يمكن اعتبار كتلة المناطق تراكمت. يتم تطبيق الأحمال الناتجة الفردية في هذه الطرق المركزية، وتمارس قوتها في نقاط محددة على طول الكَمَرَة. يمكن حساب الحمل المكافئ الناتج للكَمَرَة بأكملها باستخدام قيم ومواضع التحميل المكتشفة عن طريق جمع التحميل المكافئ الفردي للمناطق المختلفة للحصول على الحمل المعادل الناتج الكلي المتحمل على الكمرة. الخطوة التالية هي تحديد اللحظة حول نقطة محددة، وعادة ما تكون النهاية المثبتة للحاملة. تقيس اللحظة التأثير الدوراني للقوة المتحملة على الكَمَرَة. يمكن تحديد اللحظة المتوازنة عن طريق إضافة اللحظات الفردية العاملة بسبب كل حمل. تكون لحظة كل حمل هي ناتج ضرب القوة في مسافتها عن النقطة المحددة. <img alt="Equation 1" src="/files/ftp_upload/14280/14280_PT_Equation_1.svg" style="text-align: center; height: 11px;"> من خلال استحضار مبدأ العزم، تكون لحظة التحميل المعادل الناتج حول النقطة المحددة يساوي ناتج ضرب الحمل المكافئ الناتج والمسافة عن تلك النقطة. <img alt="Equation 2" src="/files/ftp_upload/14280/14280_PT_Equation_2.svg" style="text-align: center; height: 13px;"> من خلال إعادة ترتيب المعادلة واستبدال الحقول، يمكن تحديد موقع التحميل المتوازي الناتج على الكَمَرَة. <img alt="Equation 3" src="/files/ftp_upload/14280/14280_PT_Equation_3.svg" style="text-align: center; height: 35px;"></div>

الحزم هي عناصر هيكلية شائعة الاستخدام في التطبيقات الهندسية التي تتطلب قدرات حمل مختلفة. الخطوة الأولى في تحليل ...

Education

JoVE Core

Mechanical Engineering

الهندسة الميكانيكية

Unit 1

الوحدة الأولى

Force System Resultants

محصلات نظام القوى

KEY TERMS AND CONCEPTS

المصطلحات والمفاهيم الأساسية

Distributed Loads: Problem Solving

equivalent resultant loads on beams

Equivalent resultant loads on beams can be found by breaking a distributed load into smaller regions. This makes the beam easier to analyze. Each region can then be handled on its own before the results are combined.

The magnitude of the equivalent resultant load for each region comes from the area of that region. In this setting, area represents the force applied by the distributed load over that part of the beam. After finding the force for each region, the position of each resultant load must be located.

The position is found by using the centroid of each region. A centroid is the point where the region’s mass can be treated as concentrated. The individual resultant loads act at these centroids, so each force is placed at a specific point along the beam.

Once the separate forces and locations are known, they are combined to find the equivalent resultant load for the full beam. This is done by adding the individual resultant loads from the different regions. The result gives the overall force acting on the beam.

The next step is to determine the moment about a chosen point, usually the fixed end of the beam. A moment is the turning effect of a force. The total moment comes from adding the moments created by each load, and each moment equals force times distance from the chosen point.

By using the moment principle, the moment of the equivalent resultant load about that point must equal the force multiplied by its distance from the point. Rearranging that relationship makes it possible to find where the single equivalent load acts along the beam. This gives both the size and location of the load that replaces the distributed loading.

Equivalent Resultant Loads on Beams

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principle of moments

Resolving Forces in Moment Calculations

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distributed loads: problem solving

Equivalent resultant loads on beams can be found by breaking a distributed load into smaller regions. This makes the beam easier to analyze. Each region can then be handled on its own before the results are combined. The magnitude of the equivalent resultant load for each region comes from the area of that region. In this setting, area represents the force applied by the distributed load over that part of the beam. After finding the force for each region, the position of each resultant load...

key terms and concepts

Learn how to replace a distributed load with one equivalent resultant force on a beam by using areas, centroids, and moments to find its location.

Equivalent Resultant Loads on Beams | 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

Equivalent Resultant Loads on Beams

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