ENG1020 – ENGINEERING STRUCTURES
Project 3
Investigation of Alternative Overhead Pedestrian Bridge
Sandani Manjana Jayaratne – 24848352
Eranda Sampath Kulatunge – 24717150
Muhammed Akif Mazlan – 25849034
30th May, 2014
Summary
This report goes through the calculations performed to make an informed decision about which design is better suited for an Overhead Pedestrian Bridge. The bridge is to be constructed between Building 5A and Building 4 in Monash University Malaysia. The client has requested an alternative beam design for the bridge as opposed to the initial truss design. This report shows an overview of the calculations, plans and methods involved in designing the overhead pedestrian bridge.
Table of Contents
Introduction 4
Overview of the Bridge 4
Calculating Loads 4
Calculating Reactions 5
Checking For Failure (Initial Design) 8
Optimization 9
Checking For Failure (Final Design) 10
Design of the Middle Column 11
Conclusion 12
References 12
Introduction
The pedestrian bridge is to be constructed between Building 4 and Building 5A of Monash University Malaysia. The initial design for the bridge was a truss design. However, the client has requested an alternative beam design. The report explains in detail the two designs and which design is better suited for the purpose.
Design 2 (beam design) is to be constructed by steel beams, with a column in the median strip. Due to this, the beams were optimized before designing the column.
Safety was considered a top priority among other vital factors carefully planned when designing the bridge. To ensure safety, the initial beam self-weight estimate of 50kg/m was iterated several times until a suitable value was obtained. The beams were checked for...
... middle of paper ...
...ion is less than the maximum allowed deflection of 0.048m so the beam does not fail
Design of the middle column
Force/Area < σ stress
(102.37 x 〖10〗^3)/A < 350
A > 292.48mm^2
To check buckling effect :
F < (ELπ^2)/L^2
I > (FL^2)/(π^2 E)
I > (102.37 x 〖10〗^3 x 〖5400〗^2)/(π x 200 x 〖10〗^3 )
I > 1.90 x 10^6 mm^4
Hence, 114.3 x 3.6 CHS was chosen
Conclusion
The final conclusion was reached by calculating and measuring which beam would be most appropriate to support the bridge. The suitable beam was found to be 310UB : 32kg/m while the middle column is found to be 114.3 x 3. 6CHS Overall, the final conclusion we reached was that using a truss bridge is a more suitable design for the link bridge.
References
Lecture notes: Sunway and Clayton
Appendix 1 – I-beam sections
Appendix 2 – circular hollow sections
Appendix 3 – square hollow sections
ENG1020 Study Guide
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