lecture #5 trusses and frames. statically determinate trusses
TRANSCRIPT
Lecture #5Trusses and frames. Statically determinate trusses
USE OF TRUSS STRUCTURES IN AVIATION
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Junkers F.13,Germany, 1920
USE OF TRUSS STRUCTURES IN AVIATION
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FFVS,Sweden, 1942
truss sparbeam spar
USE OF TRUSS STRUCTURES IN AVIATION
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truss sparbeam spar
Concorde,Europe, 1969
USE OF TRUSS STRUCTURES IN AVIATION
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Concorde,Europe, 1969
USE OF TRUSS STRUCTURES IN AVIATION
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A300,Europe, 1972
USE OF TRUSS STRUCTURES IN AVIATION
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Zenith CH701, 1986
motor mount frame
DIFFERENCE BETWEEN TRUSSES AND FRAMES
Trusses Frames
Members are subjected to tension/compression
only
At least one member is subjected to bending,
shear or torsion
Composed of rods Composed of bars
Usually more simple to calculate, more weight
effective
Usually more simple to manufacture, and to place in tight layout
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DIFFERENCE BETWEEN TRUSSES AND FRAMES
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Connection by riveting,moment-resistant
DIFFERENCE BETWEEN TRUSSES AND FRAMES
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Connection by welding,moment-resistant
TOPIC OF THE LECTURE
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Methods of forces calculation:•Method of joints•Method of sections•Method of substitution of members
Supplementary tools:•Zero-force member identification •Principle of superposition•Use of symmetry
CONCLUSIONS
Method
of jointsMethod of sections
Method of substitution of
members
Effective for two-member joints
Effective when forces in few
certain members should be
determined
Used for complex
structures; numerical
methods should be considered as
an alternative
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WHERE TO FIND MORE INFORMATION?
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Method of joints and method of sections are covered inA. Kassimali. Structural Analysis. 2009,Chapters 4.5 and 4.6
Nice video on method of jointshttp://www.youtube.com/watch?v=-qms9xt3sbQNice video on method of sectionshttp://www.youtube.com/watch?v=Yn-9voH1gZ4
Principle of superposition and method of substitution of members are covered inA. Williams. Structural Analysis In Theory and Practice. 2009,Chapters 1.7, 2.4
… Internet is boundless …
TOPIC OF THE NEXT LECTURE
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Static determinacy. Methods of analysis
All materials of our course are availableat department website k102.khai.edu
1. Go to the page “Библиотека”2. Press “Structural Mechanics (lecturer Vakulenko S.V.)”