Name: beam shear force diagram
Uploaded: 2025-05-22T09:06:03.000Z
Duration: 1 min 27 s
Channel: JoVE

전단 다이어그램은 빔의 길이를 따른 전단력 분포를 그래픽으로 표현한 것입니다.
두 끝에서 지지되고 수직 하중을 받는 빔 AB를 고려하십시오. 전단 다이어그램을 구성합니다.
빔의 자유물체 다이어그램을 그립니다. 힘과 모멘트의 평형 방정식을 사용하여 각 지지대의 반력을 계산할 수 있습니다.
빔에 단면 방법을 적용합니다.
다음으로, 영역 AP 내의 점 A로부터 임의의 거리를 고려합니다. 섹션의 자유물체 다이어그램을 그립니다. 평형 조건에서 단면의 전단력은 지지부의 반력과 같습니다.
마찬가지로, PQ 영역 내의 임의의 점을 고려합니다. 자유물체 다이어그램을 그리고 평형 방정식을 사용하여 단면의 전단을 결정할 수 있습니다.
마지막으로, 임의의 점은 섹션 QB 내에서 고려됩니다. 자유물체 다이어그램을 그리고 평형 방정식을 불러오면 단면의 전단을 결정할 수 있으며, 이는 빔이 끝날 때까지 일정하게 유지되고 궁극적으로 평형을 유지하기 위해 0이 됩니다.

<ol>
	<li>히벨러, R.C. (2016). Engineering Mechanics \u2012 정역학 및 동역학. 뉴저지 호보켄: 피어슨 프렌티스 홀. 361쪽.</li>
	<li>맥주, F.P.; 존스턴, ER; 마주렉, D.F; 크롬웰, PJ 및 Self, BP(2019). 엔지니어를 위한 벡터 역학 \u2012 Statics and Dynamics. 뉴욕 : McGraw-Hill. 381쪽.</li>
</ol>

자유물체도

보 역학 연구에서 자유물체도는 보의 길이에 따른 전단력의 분포를 이해하는 데 중요한 역할을 합니다. 양쪽 끝이 지지되고 수직 하중을 받는 보 AB을 생각해 봅니다.
먼저 보에 작용하는 모든 외부 힘과 내부 반응을 나타내는 보의 자유물체도가 그려집니다. 힘과 모멘트의 평형방정식을 사용하여 각 지지부에서의 반응력을 계산할 수 있습니다. 주어진 보에 대해 구한 A 과 B 지점에서의 반응력의 수직 성분은 각각 24 kN과 18 kN입니다.

<img alt="Figure 1" src="/files/ftp_upload/14301/14301_PT_Figure_1v2.svg" style="text-align: center; height: 300px;">

전단도는 보의 길이에 따른 전단력의 분포를 보여주는 그래프 표현입니다. 이 자유물체도를 만들기 위해 보에 단면의 방법을 적용합니다. 다음으로, 영역 AP 내의 지점 A로부터의 임의의 거리가 고려됩니다. 이 섹션의 자유물체도는 보에 작용하는 힘을 분석하기 위해 그려집니다. 평형 조건에서 단면의 전단력은 지지대에서의 반력과 같으며, 이는 V1=24 kN.
마찬가지로, 영역 PQ 내의 임의의 점이 고려됩니다. 이 절의 자유물체도를 그리고 평형방정식을 이용하면 전단력인 V2이 결정됩니다.
<img alt="Equation 1" src="/files/ftp_upload/14301/14301_Equation_1v2.svg" style="text-align: center; height: 13px;" />
마지막으로, 섹션 QB 내에서 임의의 점이 고려됩니다. 이 섹션에 대한 자유 물체 도표가 그려지고, 평형 방정식이 호출되어 V3,라는 섹션의 전단력이 결정됩니다.
<img alt="Equation 2" src="/files/ftp_upload/14301/14301_Equation_2v2.svg" style="text-align: center; height: 13px;" />
이 전단력은 보가 끝날 때까지 일정하게 유지되며, 궁극적으로 평형을 유지하기 위해 0으로 이동합니다.

빔 역학 연구에서 전단 다이어그램은 빔의 길이를 따라 전단력의 분포를 이해하는 데 중요한 역할을 합니다. 고려하다...

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KEY TERMS AND CONCEPTS

주요 용어 및 개념

Shear Diagram

beam shear force diagram

Beam shear force diagrams show how shear changes along the length of a supported beam. In beam mechanics, they help students track the internal shear force caused by perpendicular loads. The beam AB in this example is supported at both ends, so the first step is to draw a free-body diagram that shows the external forces and internal reactions.

The reaction forces at supports A and B are found with equilibrium equations for force and moment. For the beam shown, the vertical reaction at A is 24 kN and the vertical reaction at B is 18 kN. These values become the starting point for building the shear diagram.

To form the shear diagram, the method of sections is used. A point is chosen at an arbitrary distance from A in the region AP, and a free-body diagram of that section is drawn. From equilibrium, the shear force in that section is V1 = 24 kN.

The same process is repeated in the region PQ. An arbitrary point is selected, the section is isolated, and the equilibrium equation is applied to find V2. A third section is then taken in the region QB. Its free-body diagram gives V3, which stays constant until the end of the beam and then goes to zero so the beam remains in equilibrium.

Beam Shear Force Diagram

sign convention

Beam Forces: Tension, Shear, and Bending

Beam analysis depends on the internal forces and moments inside a structure. These include normal force, shear force, and bending moment. Engineers use the method of sections to cut the beam and find these values. A sign convention helps show whether each result is positive or negative. Normal force acts perpendicular to the beam’s cross-section. It can pull the material in tension or push it in compression. Tension is taken as positive, while compression is taken as negative. This makes it...

normal and shear force

Beam Loads and Internal Forces

Beam loads create internal forces inside a structure. Weight, pressure, and other external forces can all act on a beam. These internal forces affect the beam’s stability and strength. Engineers study these forces to find their size and direction. A common approach is the method of sections. In this method, an imaginary cut is made at a chosen point on the beam, and the forces at that section are analyzed. One internal force is the normal force, also called the axial force. It acts...

bending and torsional moments

Forces That Bend and Twist Materials

Bending and torsional moments describe how materials respond to force. These ideas are important in structural engineering because they help explain how beams, rulers, and screws change shape under load. A moment depends on both the size of the force and the distance from the point of interest to the force’s line of action. A bending moment forms when an external force makes a structural element bend. If the element bends upward, the top side is in compression and the bottom side is in tension.

internal loadings in structural members: problem solving

internal-loadings-in-structural-members-problem-solving

Beam Internal Force Analysis at Point A

Beam internal force analysis shows how normal force, shear force, and bending moment act inside a structural member. These internal loadings help engineers check whether a beam can support the external forces applied to it. The example uses a beam OC that weighs 5 kN and is inclined at 53.13° with the horizontal. The beam is supported at both ends. The goal is to find the internal loadings at point A. The first step is to find the reaction force at point C. This is done by taking the moment...

beams

Beam Types and Support Conditions

Beams are key parts of structural engineering and construction. They support loads that act at different points along their length. Engineers use beam shape and support conditions to understand how a beam will perform. Beams can be classified by geometry. Straight beams are the most common and have a constant cross-section along their length. Tapered beams change in cross-section from one end to the other, while curved beams have a curved shape. Beam cross-section also matters. Common shapes...

shear diagram

Beam shear force diagrams show how shear changes along the length of a supported beam. In beam mechanics, they help students track the internal shear force caused by perpendicular loads. The beam AB in this example is supported at both ends, so the first step is to draw a free-body diagram that shows the external forces and internal reactions. The reaction forces at supports A and B are found with equilibrium equations for force and moment. For the beam shown, the vertical reaction at A is 24...

bending moment diagram

Beam Load Analysis with Moment Diagrams

Beam load analysis uses a bending moment diagram to show how bending changes along the length of a beam. This diagram helps engineers and designers check whether a structure can handle applied forces. It is also useful for parts such as shelving arms, which must resist forces and moments from a load. To build the diagram, start by finding the reactive forces and any couple moments on the beam. In some cases, especially when a beam is inclined, these forces must be resolved into components that...

relation between the distributed load and shear

relation-between-the-distributed-load-and-shear

Shear Change Under Distributed Loading

Shear force changes along a beam under a distributed load. In structural analysis, this relationship helps explain how beams respond to loading conditions that also include concentrated loads and a couple moment. To study the link, consider a small beam section that has no concentrated load or couple moment on it. Draw a free-body diagram for that elemental section. It includes the distributed load along the beam, the shear force V(x) on the right-hand side of the cut, and a small added shear...

relation between the shear and bending moment

relation-between-the-shear-and-bending-moment

Shear and Moment Diagrams in Beam Loads

Shear and moment diagrams help show how a beam responds to loads. A beam can carry a distributed load, concentrated loads, and a couple moment. These loads create internal shear forces and bending moments. The beam is examined by isolating a small elemental section and drawing a free-body diagram. For that section to stay in equilibrium, the moment on the right side must be slightly larger than the moment on the left side. The distributed load also has a resultant force that acts at a...

shear and bending moment diagram: problem solving

shear-and-bending-moment-diagram-problem-solving

Beam Load Analysis with Shear Diagrams

Beam load analysis uses shear and bending moment diagrams to track the internal forces in a beam. These diagrams are important when a beam carries concentrated loads and a distributed load. They help show how the beam responds so structures can be designed safely and efficiently. The first step is to draw a free-body diagram of the whole beam. A free-body diagram shows the concentrated loads, the distributed load, and the reaction forces at the supports. Use the equilibrium equations, where...

cable subjected to concentrated loads

Finding Tension in a Loaded Cable

Flexible cables can carry vertical point loads between two fixed supports. The cable is treated as flexible, inextensible, and nearly weightless. Under these conditions, it changes shape to form straight-line segments, and each segment carries a constant tensile force. To analyze the cable, a free-body diagram is drawn for the whole cable. This helps identify the reaction forces at the supports. In many cases, the number of unknown reaction components is greater than the available equilibrium...

cable subjected to a distributed load

Finding Cable Shape Under Distributed Load

Cable shape under a distributed load is found by analyzing the forces along a small piece of the cable. This method is important in suspension bridge design because the main cables must carry changing loads safely. The load causes the tensile force in the cable to change, and it also creates cable deformation. The analysis starts with a free-body diagram of a short cable segment. The diagram shows the distributed load and the change in tensile force across that segment. Equilibrium equations...

cable subjected to its own weight

Cable Sag Under Its Own Weight

Overhead power transmission cables sag under their own weight, and that shape affects how they carry electricity across long distances. To study this behavior, the cable is analyzed with a generalized loading function. This function treats the load along the cable's arc length instead of its projected length, which gives a more accurate picture of the cable's response. The analysis then focuses on a small cable segment. A free-body diagram is drawn to show the forces acting on that segment.

cable: problem solving

Cable Tension Under Uniform Loading

Cable tension under uniform loading is found by analyzing a cable fixed between two supports. The problem starts with the support conditions and the load on the cable. From there, the cable’s shape must be described with an equation that matches the curve formed by the load. The next step is to integrate the shape equation to get the cable’s shape function. This makes it possible to solve for constants in the equation. The boundary condition at the origin gives one constant. The slope, which...

key terms and concepts

Learn how to build a beam shear force diagram using free-body diagrams, reaction forces, and the method of sections for a supported beam.

Beam Shear Force Diagram | 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

Beam Shear Force Diagram

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