Search the courses, subjects, tracks, games and features, or jump straight to a page.
Learn it your way
A short class with Sarah and her students. The other ways are under More.
Sign up free to listen. Transcripts are free to read.
Today we will learn about statically determinate beams. These are beams that can be fully analyzed using just the equilibrium equations without additional information. Can anyone remind me what the equations of equilibrium are?
They are the sum of forces in both x and y directions should equal zero, and the sum of moments should also equal zero.
Exactly! Now, can someone name a type of statically determinate beam?
A simply supported beam!
Correct! A simply supported beam rests on two supports and can rotate freely. This flexibility is essential for load distribution. Remember the mnemonic 'SIMPLE' for these beams: S for Supports, I for Internal reactions, M for Moments can be calculated easily, P for Practical applications, L for Loads can be distributed.
What about one-sided over-hanging beams?
Great question. One-sided over-hanging beams extend beyond one support but still allow for simple analysis. Are there any questions about these concepts before we move on?
Now, let's discuss statically indeterminate beams. Unlike the previous type, these beams require more equations for a complete analysis. Can anyone provide an example?
Continuous beams!
Correct again! Continuous beams extend over more than two supports. Because of this, the internal forces become more complex. Remember the acronym 'C-SQUARE': C for Continuous, S for Supports that complicate the analysis, Q for Questions about internal forces, U for Understanding necessary for solving, A for Applications in structural integrity, R for Reactions that need careful consideration, and E for Equations that involve additional factors.
What about cantilever beams? Are they statically indeterminate?
Good thought! End-supported cantilever beams are a type where one end is fixed and the other is free, making the analysis a bit more challenging. Any more questions?
Let’s solidify our understanding with some examples. Who can explain the impact of beam type on load capacity?
I think a cantilever beam would hold less load at the free end compared to a simply supported beam.
Exactly! The fixed support on the cantilever adds complexity. This is why remembering their configurations aids analysis. Can anyone share how to determine which beam to use based on a construction project?
Maybe by assessing the amount and type of load and support available?
That's right! Always consider loads, where supports are placed, and how the beams will behave under those conditions. We can remember ‘LOADS’ as: L for Loads types, O for Optimal support location, A for Analyze appropriately, D for Distribution of forces, and S for Structural integrity.
That makes it easier to remember the factor!
Can be analyzed with basic equilibrium equations.
Require additional equations or information for analysis.
Classic configuration with support at both ends.
One end is fixed, offering specific challenges in load handling.
Span over multiple supports, allowing for complicated load distributions.
Beams can sway and beams can roll, both can bear a heavy load. But one is straight, and the other can bend, depending on support at each end.
Once there was a bridge made of a continuous beam, stretching over many pillars. This bridge was strong but could not stand alone; it needed support from the ground to bear the load of cars running back and forth.
For statically determinate: S - Simple supports, I - Internal reactions, M - Moments calculated, P - Practical usage, L - Load distribution, E - Easy equations.
C-SQUARE: C for Continuous, S for Supports, Q for Questions about internal forces, U for Understanding, A for Applications, R for Reactions, E for Equations.
Term
Simply Supported Beam
Click to flip
Term
Cantilever Beam
Click to flip
Term
Continuous Beam
Click to flip
Term
Statically Determinate Beams
Click to flip
Term
Statically Indeterminate Beams
Click to flip
Beams whose reactions can be determined using static equilibrium equations alone.
Beams that cannot be solved for reactions and internal forces using only the equations of static equilibrium.
Beams supported at both ends with a single span.
A beam that is fixed at one end and free at the other.
A beam that spans over more than two supports.
Beams that extend beyond their supports.
This section discusses different types of beams, categorizing them into statically determinate and statically indeterminate beams.
Beam types are crucial in structural engineering, and they are categorized into statically determinate beams and statically indeterminate beams. This section outlines several specific beam configurations, including simply supported beams, cantilever beams, and continuous beams, each with its characteristics and applications.
In structural engineering, beams are members designed to support loads, and understanding their types is fundamental for accurate analysis and application.
Beams can be categorized as follows:
Statically Determinate Beams: These beams can be analyzed using the equations of equilibrium alone without needing additional material properties or support constraints. Examples include:
Statically Indeterminate Beams: These beams require more information than just the equations of equilibrium for analysis, including material properties and geometry. Examples include:
Understanding these types of beams is essential as they define methods for analyzing forces, moments, and reactions due to applied loads.