Lecture #7Shear centerin opened cross section

SHEAR STRESSES RELATED QUESTIONS

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- shear flows due to the shear force, with no torsion;

- shear center;

- torsion of closed contour;

- torsion of opened contour, restrained torsion and deplanation;

- shear flows in the closed contour under combined action of bending and torsion;

- twisting angles;

- shear flows in multiple-closed contours.

SHEAR CENTER - ILLUSTRATION

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CALCULATION OF SHEAR CENTER POSITION

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Way of calculation:

1) calculate shear flows q from the arbitrary chosen

force Qy;

2)calculate the moment of shear flows MC (q) about

some point C;

3)the X coordinate of SC will be

4)make similar calculations to find YSC.

CSC C

y

M qX X

Q

CALCULATION OF SHEAR CENTER POSITION

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Properties of symmetrical cross sections:

1) The shear center lays on the axis of symmetry.

2) Thus, for twice symmetrical section the shear center is the point of symmetry axes intersection.

If the cross section is composed of segments converging in a single point, this point is the shear center:

WHERE TO FIND MORE INFORMATION?

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Megson. An Introduction to Aircraft Structural Analysis. 2010Chapter 16.2

… Internet is boundless …

TOPIC OF THE NEXT LECTURE

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Torsion of thin-walled beams with opened cross sections

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.)”