Types of Supports
Fixed Support
Fixed supports can provide a reaction from a force from almost any angle (along the axis, or from directly above), therefore, if the angle is not directly horizontal or vertical, we can resolve the angle into it’s vertical and horizontal components.
Fixed supports can have two unknown (resolved) reaction forces,
Roller Support
A Roller applies very little resistance to forces applied along the axis of the beam (horizontally), if you applied a force there the roller would probably roll or something.
Roller supports only have one unknown reaction force, one applied directly purpendicular
Cantilever’s Embedded Support
Cantilevers are embeded in a material, thus they resist forces horizontal and vertical forces like a Fixed Support, but also have a moment that prevents rotation since they are embeded. CantileverReaciton.excalidraw
- On the bending moment graph, it is pretty much always negative, th
- This is unlike the other B.M graphs where if the Shear Force Diagram is postiive, then the B.M graph is also positive.
Types of Loads
Concentrated Loads
Uniformally Distributed Loads
Loads distributed uniformally can be represented as a single force at the centrepoint, with the Kn/m value turned into kN e.g.
- 4m long U.D.L
- That applies a load of 5kN/m = 20kN at it’s midpoint 600 On a Shear Force Diagram, the left most side of the UDL is the start of a linear line going to the right most side, even though there is a force acting in the middle.
UDL on the Shear Force Diagram
The maximum bending moment is where the line crosses the horizontal 0 axis on the shear force diagram.