UNIVERSITY OF JOHANNESBURG
Department of Civil Engineering Science
Structural Engineering 3A (SUS3A11/SUSCIA3): Assignment 3 (Group Project)
Issue date: 08/05/2025
Due date 21/05/2025 (11:30Am)
Note: Marks will be deducted for late submission (15 marks/day of delay).
A client has approached your consulting engineering firm to perform the structural analysis of a proposed
billboard to be installed alongside a major highway in Pretoria. Figure 1 illustrates a similar structure to
the one under consideration.
Figure 1: Typical billboard structure
Additional information:
Site Location: Pretoria
Self-weight of billboard: To be estimated (Assume there is a sign on either side)
The loading on the structure comprises the following components:
•
Truss self-weight (dead load). Assume the vertical members weigh 25 kg/m and increase this by
20% to allow for the horizontal members and diagonals.
•
Signage weight and camera weights (dead load). The cameras are cylindrical with a diameter of
200 mm and 500 mm long and mass of 180 kg. Allow an extra 100 kg for lighting equipment and
fittings. You must decide where to attach these on the truss structure and explain this clearly on
your report The signs are made of steel and you must decide on the appropriate dimensions.
•
Maintanance access flooring, positioned between the two planar vertical trusses, and safety
barriers (dead load)
•
Maintanance live loading on the platform (live load)
•
Horizontal wind loading (wind load)
Design tasks:
a) Calculate the vetical loads acting on the system and draw free body diagrams showing these loads.
b) Calculate the wind loading on the system and present the results on a free body diagram.
c) Identify the distinct factored load combinations (ULS) applicable to this system. Refer to the
relevant SANS 10160 codes of practice. Compute the factored loads for the D+L and D+W load
conditions only.
d) Show Free body diagrams for both load cases-Draw neat diagrams.
e) Analyse a typical planar vertical truss based on the Ultimate limit State loading (ULS). Use the
method of Joints or the method of section. Do this only for D+L load case.
f) Calclate the size of the concrete spread footing required to resist overturning with a factor of
safety of 1.5
g) Verify your calculations in e above through the use of an open source Structural analysis software
package and include the output in your report. You can use Prokon or any other software package.
h) Evaluate the numerical results. Some questions to consider: What are the peak tensile and
compressive member forces? . Do these values seem reasonable?
i) Present all of the above in a clear and concise design report as detailed below.
Assessment:
This project is worth 10% of your final module mark and it includes;
•
A written report
•
Group presentation during the tutorial sessions
Written Report marks breadown:
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Overall report structure,quality and clarity (see below suggested report format) (10%)
•
Loading analysis (50%)
•
Truss analysis (30%)
•
Drawings and use of a software package(s) (10%)
Report format:
Suggested’ report section headings:
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Summary – Give a brief overview of the aim, method, and your results.
•
Table of Contents – Provide section, sub-section and page numbers in a clear layout.
•
Introduction – Explain the topic, the aims of the project, and the purpose of the report.
•
Assumptions – State any assumptions made in your analyses and design of the structure.
•
Loading – Provide a clear explanation of your loading and load cases considered.
•
Analysis – A brief statement of your analysis method with results clearly and concisely presented
(on diagrams and in tables wherever possible). Detailed calculations to be provided in the
Appendices.
•
Discussion and Conclusion (no more than half to one page of text is necessary).
Personal contribution and learning of not more than a half of a page by each individual member of the
team outlining your contribution to the project and what you learnt from the project.
•
Appendices
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References. Use Havard referencing style
Note: Any information that is missing from this design brief should be reasonable assumed and these
assumptions should be stated clearly in the design report. These assumptions should be properly justified.
•
Make reference to the relevant South African design standards.