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

עומס מבוזר הוא סוג של עומס המפוזר על פני משטח או מבנה.
חשבו על מדף ספרים המורכב מספרים. משקל הספרים מחולק באופן שווה על פני השטח.
הלחץ במקומות שונים על פני השטח מתאים לעומס המופעל על השטח ונמדד בניוטון למטר רבוע או פסקלס.
חשבו על סכר הידרואלקטרי, שבו המשטח השקוע מעוצב כלוח מלבני.
עבור אלמנט קטן באורך dx; הכוח המופעל על האלמנט יכול לבוא לידי ביטוי כעומס מבוזר הנתון על ידי wdx.
על ידי שילוב הכוח המופעל על האלמנט, נקבע העומס הכולל, השווה בגודלו לשטח הכולל מתחת לעקומת העומס, וקו הפעולה שלו עובר דרך הצנטרויד של השטח.
הנקודה שבה מופעל הכוח המתקבל ידועה כמרכז הלחץ.

<ol>
	<li>היבלר, R.C. (2016). מכניקה הנדסית - סטטיקה ודינמיקה. הובוקן, ניו ג'רזי: אולם פירסון פרנטיס. עמ' 190</li>
	<li>באר, פ"פ; ג'ונסטון, א.ר.; מזורק, ד"ו; קרומוול, פי ג'יי וסלף, B.P. (2019). מכניקה וקטורית למהנדסים - סטטיקה ודינמיקה. ניו יורק: מקגרו-היל. עמ' 262.</li>
</ol>

עומסים מבוזרים

Distributed Loads

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 עומסים מבוזרים הם סוג נפוץ של עומס בו נתקלים מהנדסים ומדענים במצבים מעשיים שונים. עומסים מבוזרים מתייחסים לרוב לסוג של עומס המפוזר על פני משטח או מבנה וניתן לעצב אותם ככוח מתמשך ליחידת שטח. 

 לדוגמה, חשבו על מדף ספרים מלא בספרים הנערמים אנכית צמודים זה לזה. משקל הספרים מתחלק באופן שווה לאורך המדף. כתוצאה מכך, הלחץ במקומות שונים על פני המדף מתאים לעומס המופעל ונמדד בניוטון למ"ר, או פסקל. 

במונחים של יישום אחר, חשבו על סכר הידרואלקטרי, שעבורו המשטח השקוע מעוצב כלוח מלבני. ניתן לבטא את הכוח המופעל על אלמנט קטן של הלוח באורך dx כעומס המפוזר, שניתן על ידי wdx, כאשר "w" הוא הכוח ליחידת שטח. ניתן לקבוע את העומס הכולל המופעל על הלוח על ידי שילוב הכוח המופעל על כל אלמנט קטן. גודל הכוח הנוצר המופעל על הלוח הוא פרופורציונלי לשטח מתחת לעקומת העומס, וקו הפעולה שלו עובר דרך מרכז השטח. נקודה זו ידועה כמרכז הלחץ. מרכז הלחץ חיוני בתכנון מבנים שיכולים לעמוד בכוחות חיצוניים.

דוגמאות לעומסים מבוזרים כוללים עומסי שלג על גג בניין, עומסי רוח הפועלים על מבנה, או אפילו משקל של מכונית על גשר. הבנת עומסים מבוזרים היא חיונית לתכנון מבנים בטוחים וחזקים שיכולים לעמוד בכוחות חיצוניים.</div>

עומסים מבוזרים הם סוג נפוץ של עומס שמהנדסים ומדענים נתקלים בו במצבים מעשיים שונים. עומסים מבוזרים מתייחסים לעתים קרובות ...

Education

JoVE Core

Mechanical Engineering

הנדסת מכונות

Unit 1

יחידה 1

Force System Resultants

תוצאות מערכת כוחות

KEY TERMS AND CONCEPTS

מונחים ומושגים מרכזיים

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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