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Practice these sample cases with VisualAnalysis:

1) Simple Beam (units: kips and feet, 1 kip = 1000 lbs):

Solution:

2) Continuous Beam (units: kips and feet):

Solution:

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3) Truss (units: kN and meters)

Solution:

Some Hints: Use the appropriate structure type when you start a new file. Use “Plane Truss/Frame” whenever you are

analyzing a 2D system. Only switch to the “Space Truss/Frame” if you are analyzing a true 3D system. If you have only nodal loads and if your structure behaves as a truss (only tension/compression members), select “Plane Truss”. If your structure is loaded laterally (as a beam would be) and not only at the nodes, then select “Plane Frame”.

Make sure you are using correct units (EDIT > PROJECT UNITS).

Set your grid (and snaps) before you draw anything so that you just have to click on grid points (PROJECT MANAGER, GRIDS tab). You can correct a member length and orientation after drawing by clicking a node to which it is connected and changing its coordinates in the Project Manager.

You need to assign a specific section (e.g. a steel or wood cross-section, pick from database) and its material to members. This won’t have an effect on the force/moment/shear calculations but the program expects it for accurate deflection calculations.

Put your loads into the appropriate load case (select before placement at the bottom of the screen). You do not have to consider self-weight – it is already contained in the “D” Dead Load load case. For most cases, just select the Live Load (“L”) case before you add your loads to the model.

Always start with a linear analysis (“First Order”) – that is an analysis similar to your hand-calculations. If VisualAnalysis refuses to analyze, then you may not have defined (sufficient) supports and the system can move. Try adding some more (realistic) supports.

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Do a “P-Delta” analysis when you are interested in buckling failures (to check if a column is sufficiently sized). The software does not allow us to do a correct buckling analysis but this is a good start. If this analysis fails, pick a larger size for your compression members.

If the results don’t look as expected, check your supports (your model may also be over-constrained). Also, remember that for analyzing a truss in “Plane Frame” mode (only in that case), you need to allow rotation of both ends of all truss members (i.e. make those pin joints). For this, highlight all truss members and select “simple connect” from the “connections” section in the Project Manager.

Afterwards all members should have little circles on both ends (if you enabled display of “End Releases” on the Filter tab).

VisualAnalysis structural member (“local”) coordinate system:

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More examples: Model these in VisualAnalysis. Assume appropriate load distributions and assume appropriate loads. Sketch the free-body diagrams on the right.

1 – Concrete beam

2 – Balcony support

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3 - Canopy

4 – Truss bridge