Name: truss force analysis at joints a to e
Uploaded: 2023-09-22T11:49:24.000Z
Duration: 1 min 30 s
Channel: JoVE

ضع في اعتبارك هيكل الجمالون مع وصلات خالية من الاحتكاك مثبتة على الحائط ودعم الأسطوانة على الأرض. إذا تم تطبيق قوة مقدارها 150 نيوتن على المفصل A ، فحدد القوى في كل عضو من أعضاء الجمالون.
يمكن تحديد القوى في كل مفصل باستخدام طريقة المفاصل.
أولا ، يمكن تحديد الزاوية بين الأعضاء AC و AB على أنها معكوس تان لنسبة طول BC و AB.
ثانيا ، ارسم مخططا للجسم الحر للمفصل A وقم بحل القوى في مكوناتها. من خلال تطبيق معادلات التوازن ، يمكن تحديد القوى المجهولة.
بعد ذلك ، من خلال رسم مخططات الجسم الحر للمفاصل B و C ، واستخدام معادلات التوازن ، يمكن تحديد القوى المجهولة في المفاصل B و C.
أخيرا ، ارسم مخططا للجسم الحر للمفاصل D و E. بالنسبة للأعضاء CD و EF ، قم بحل القوى في المكونات الأفقية والرأسية. يمكن تحديد القوى المجهولة في المفاصل D و E باستخدام معادلات التوازن.

<ol>
	<li>هيبلر ، آر سي (2016). الميكانيكا الهندسية - الإحصاء والديناميكيات. هوبوكين ، نيو جيرسي: قاعة بيرسون برنتيس. ص 276-277.</li>
</ol>

لم يتم الإعلان عن أي تضارب في المصالح.

طريقة الوصلات: حل المشكلات ii

<div style="direction:rtl">
	افترض وجود هيكل قوسي مع وصلات خالية من الاحتكاك مثبتة على جدار ودعامة منزلقة. إذا تم تطبيق قوة قدرها 150 نيوتن على الوصلة A، يمكن تحديد القوى في كل عضو من أعضاء القوس باستخدام طريقة الوصلات. 

<img alt="Figure 1" src="/files/ftp_upload/14283/14283_PT_Fig_1v2.svg" style="text-align: center; height: 350px;" /> 

يمكن العثور على الزاوية بين العضوين AC و AB عن طريق أخذ الظل العكسي لنسبة أطوال BC و AB، والنتيجة الناتجة هي 67.38 درجة. يتم النظر في رسم الجسم الحر للوصلة A، ويتم حل جميع القوى المجهولة إلى مكوناتها المناسبة. 

يمكن بعد ذلك استخدام شرط توازن القوة الرأسية لحساب القوة المؤثرة على العضو CA، والتي تساوي 173.08 نيوتن. 

<img alt="Equation 1" src="/files/ftp_upload/14283/14283_PT_Equation_1v2.svg" style="text-align: center; height: 15px;" /> 

وبالمثل، يمكن استخدام شرط توازن القوة الأفقية لإيجاد القوة FAB التي تساوي 161.54 نيوتن. 

<img alt="Equation 2" src="/files/ftp_upload/14283/14283_PT_Equation_2v2.svg" style="text-align: center; height: 15px;" /> 

تم النظر في رسومات الجسم الحر للوصلات B و C، وتطبيق شروط توازن القوة الرأسية والأفقية لحساب القوى المجهولة FBD وFCD وFEC. القيم الناتجة لـFBD وFCD وFEC هي 161.53 نيوتن و173.08 نيوتن و207.70 نيوتن على التوالي. 

وأخيرًا، تم النظر في رسومات الجسم الحر للوصلات D و E، وتطبيق شروط توازن القوة الرأسية والأفقية. وهذا يعطي قيم FED وFDF التي تساوي 138.46 نيوتن و265.39 نيوتن على التوالي.</div>

طريقة الوصلات: حل المشكلات II

ضع في اعتبارك هيكل الجمالون مع وصلات خالية من الاحتكاك مثبتة على الحائط ودعامة الأسطوانة. إذا تم تطبيق قوة 150 نيوتن على المفصل A ، فإن القوى الموجودة في كل ...

Education

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Mechanical Engineering

الهندسة الميكانيكية

Unit 1

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Structural Analysis

التحليل الإنشائي

KEY TERMS AND CONCEPTS

المصطلحات والمفاهيم الأساسية

Method of Joints: Problem Solving II

truss force analysis at joints a to e

Truss force analysis at joints A to E uses the method of joints to find the force in each member. The truss has frictionless joints, a wall support, and a roller support. A 150 N force is applied at joint A, and the member forces are solved from joint to joint.

First, the angle between members AC and AB is found using the inverse tangent of the ratio of BC to AB. This gives an angle of 67.38°. A free-body diagram of joint A is then drawn, and each unknown force is split into vertical and horizontal components.

The vertical force equilibrium equation is used to find the force in member CA, which is 173.08 N. The horizontal force equilibrium equation gives the force in member AB as 161.54 N. Free-body diagrams for joints B and C are then used to continue the calculation.

At joints B and C, the vertical and horizontal equilibrium conditions are applied again. This gives FBD = 161.53 N, FCD = 173.08 N, and FEC = 207.70 N. Free-body diagrams of joints D and E are used last, and the same equilibrium steps give FED = 138.46 N and FDF = 265.39 N.

Truss Force Analysis at Joints A to E

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Truss force analysis at joints A to E uses the method of joints to find the force in each member. The truss has frictionless joints, a wall support, and a roller support. A 150 N force is applied at joint A, and the member forces are solved from joint to joint. First, the angle between members AC and AB is found using the inverse tangent of the ratio of BC to AB. This gives an angle of 67.38°. A free-body diagram of joint A is then drawn, and each unknown force is split into vertical and...

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key terms and concepts

Use the method of joints to solve truss forces at joints A to E. Find member forces from free-body diagrams, angles, and equilibrium equations.

Truss Force Analysis at Joints A to E | 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

Truss Force Analysis at Joints A to E

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