Roark's Formulas for Stress and Strain
Properties of sections - table A.1 (1-14)
A=area (mm2), x/y= distance to extreme fiber (mm), I=moment of inertia (mm4), r=radius of gyration (mm), Z=plastic section modulus (mm3), SF = shape factor
1. SQUARE
square
distance a (mm): 
angle alfa (degrees): 
 
A square (mm2): A
yc square (mm): yc
xc square (mm): xc
y'c square (mm): y'c
Ix square (mm4): Ix
Iy square (mm4): Iy
I'x square (mm4): I'x
rx square (mm): rx
ry square (mm): ry
r'x square (mm): r'x
Zx square (mm3): Zx
Zy square (mm3): Zy
SFx square: SFx
SFy square: SFy
2. RECTANGLE
rectangle
distance b (mm): 
distance d (mm): 
 
A rectangle (mm2): A
yc rectangle (mm): yc
xc rectangle (mm): xc
Ix rectangle (mm4): Ix
Iy rectangle (mm4): Iy
rx rectangle (mm): rx
ry rectangle (mm): ry
Zx rectangle (mm3): Zx
Zy rectangle (mm3): Zy
SFx rectangle: SFx
SFy rectangle: SFy
3. HOLLOW RECTANGLE
hollow_rectangle
distance b (mm): 
distance d (mm): 
distance bi (mm): 
distance di (mm): 
 
A hollow rectangle (mm2): A
yc hollow rectangle (mm): yc
xc hollow rectangle (mm): xc
Ix hollow rectangle (mm4): Ix
Iy hollow rectangle (mm4): Iy
rx hollow rectangle (mm): rx
ry hollow rectangle (mm): ry
Zx hollow rectangle (mm3): Zx
Zy hollow rectangle (mm3): Zy
SFx hollow rectangle: SFx
SFy hollow rectangle: SFy
4. TEE SECTION
tee
distance b (mm): 
distance d (mm): 
thickness t (mm): 
thickness tw (mm): 
 
A tee section (mm2): A
yc tee section (mm): yc
xc tee section (mm): xc
Ix tee section (mm4): Ix
Iy tee section (mm4): Iy
rx tee section (mm): rx
ry tee section (mm): ry
Zx tee section (mm3): Zx
Neutral axis x - from the bottom (mm): NAx
Neutral axis x - from the top (mm): NAx
Zy tee section (mm3): Zy
SFx tee section: SFx
SFy tee section: SFy
5. CHANNEL SECTION
channel
distance b (mm): 
distance d (mm): 
thickness t (mm): 
thickness tw (mm): 
 
A channel section (mm2): A
yc channel section (mm): yc
xc channel section (mm): xc
Ix channel section (mm4): Ix
Iy channel section (mm4): Iy
rx channel section (mm): rx
ry channel section (mm): ry
Zx channel section (mm3): Zx
Neutral axis x - from the bottom (mm): NAx
Neutral axis x - from the top (mm): NAx
Zy channel section (mm3): Zy
SFx channel section: SFx
SFy channel section: SFy
6. WIDE-FLANGE BEAM WITH EQUAL FLANGES
wide_flange_beam_with_equal_flanges
distance b (mm): 
distance d (mm): 
thickness t (mm): 
thickness tw (mm): 
 
A wide-flange beam (mm2): A
yc wide-flange beam (mm): yc
xc wide-flange beam (mm): xc
Ix wide-flange beam (mm4): Ix
Iy wide-flange beam (mm4): Iy
rx wide-flange beam (mm): rx
ry wide-flange beam (mm): ry
Zx wide-flange beam (mm3): Zx
Zy wide-flange beam (mm3): Zy
SFx wide-flange beam: SFx
SFy wide-flange beam: SFy
6bis. WIDE-FLANGE BEAM WITH UNEQUAL FLANGES (b2 >= b1)
wide_flange_beam_with_unequal_flanges
distance b1 (mm): 
distance b2 (mm): 
distance h (mm): 
thickness th1 (mm): 
thickness th2 (mm): 
thickness tv (mm): 
 
A wide-flange beam unequal flanges (mm2): A
Ix wide-flange beam unequal flanges (mm4): Ix
Iy wide-flange beam unequal flanges (mm4): Iy
distance bottom - neutral axis x (mm): NAx
distance right - neutral axis y (mm)(b2/2): NAy
7. EQUAL-LEGGED ANGLE
equal_legged_angle
distance a (mm): 
thickness t (mm): 
 
A equal-legged angle (mm2): A
yc1 equal-legged angle (mm): yc1
yc2 equal-legged angle (mm): yc2
xc equal-legged angle (mm): xc
Ix equal-legged angle (mm4): Ix
Iy equal-legged angle (mm4): Iy
rx equal-legged angle (mm): rx
ry equal-legged angle (mm): ry
Zx equal-legged angle (if t/a>= 0,40) (mm3): Zx1
Zx equal-legged angle (if t/a<= 0,40) (mm3): Zx2
yp equal-legged angle if t/a >= 0,40 (mm): yp1
yp equal-legged angle if t/a <=0,40 (mm): yp2
8. UNEQUAL-LEGGED ANGLE
unequal_legged_angle
distance b (mm): 
distance d (mm): 
thickness t (mm): 
 
A unequal-legged angle (mm2): A
yc unequal-legged angle (mm): yc
xc unequal-legged angle (mm): xc
Ix unequal-legged angle (mm4): Ix
Iy unequal-legged angle (mm4): Iy
Ixy unequal-legged angle (mm4): Ixy
rx unequal-legged angle (mm): rx
ry unequal-legged angle (mm): ry
9. EQUILATERAL TRIANGLE
equilateral_triangle
distance a (mm): 
angle alfa (degrees): 
 
A equilateral triangle (mm2): A
yc equilateral triangle (mm): yc
xc equilateral triangle (mm): xc
y'c equilateral triangle (mm): y'c
Ix equilateral triangle (mm4): Ix
Iy equilateral triangle (mm4): Iy
Ix' equilateral triangle (mm4): Ix'
rx equilateral triangle (mm): rx
ry equilateral triangle (mm): ry
rx' equilateral triangle (mm): rx'
Zx equilateral triangle (mm3): Zx
Zy equilateral triangle (mm3): Zy
SFx equilateral triangle: 2.343
SFy equilateral triangle: 2.000
neutral axis x distance from the base (mm): NA
10. ISOSCELES TRIANGLE
isosceles_triangle
distance b (mm): 
distance d (mm): 
 
A isosceles triangle (mm2): A
yc isosceles triangle (mm): yc
xc isosceles triangle (mm): xc
Ix isosceles triangle (mm4): Ix
Iy isosceles triangle (mm4): Iy
rx isosceles triangle (mm): rx
ry isosceles triangle (mm): ry
Zx isosceles triangle (mm3): Zx
Zy isosceles triangle (mm3): Zy
SFx isosceles triangle: 2.343
SFy isosceles triangle: 2.000
neutral axis x distance from the base (mm): NA
11. TRIANGLE
triangle
distance a (mm): 
distance b (mm): 
distance d (mm): 
 
A triangle (mm2): A
yc triangle (mm): yc
xc triangle (mm): xc
Ix triangle (mm4): Ix
Iy triangle (mm4): Iy
Ixy triangle (mm4): Ixy
Tetax triangle (degrees): Tetax
rx triangle (mm): rx
ry triangle (mm): ry
12. PARALLELOGRAM
parallelogram
distance a (mm): 
distance b (mm): 
distance d (mm): 
 
A parallelogram (mm2): A
yc parallelogram (mm): yc
xc parallelogram (mm): xc
Ix parallelogram (mm4): Ix
Iy parallelogram (mm4): Iy
Ixy parallelogram (mm4): Ixy
Tetax parallelogram (degrees): Tetax
rx parallelogram (mm): rx
ry parallelogram (mm): ry
13. DIAMOND
diamond
distance b (mm): 
distance d (mm): 
 
A diamond (mm2): A
yc diamond (mm): yc
xc diamond (mm): xc
Ix diamond (mm4): Ix
Iy diamond (mm4): Iy
rx diamond (mm): rx
ry diamond (mm): ry
Zx diamond (mm3): Zx
Zy diamond (mm3): ry
SFx diamond : 2.000
SFy diamond : 2.000
14. TRAPEZOID
trapezoid
distance a (mm): 
distance b (mm): 
distance c (mm): 
distance d (mm): 
 
A trapezoid (mm2): A
yc trapezoid (mm): yc
xc trapezoid (mm): xc
Ix trapezoid (mm4): Ix
Iy trapezoid (mm4): Iy
Ixy trapezoid (mm4): Ixy

ENGLISH NEDERLANDS
area oppervlakte
distance to extreme fibre afstand tot de uiterste vezel
moment of inertia traagheidsmoment
radius of gyration traagheidsstraal
plastic section modulus plastisch weerstandsmoment
shape factor vormfactor
square vierkant
rectangle rechthoek
hollow rectangle holle rechthoek
tee section T profiel
channel section U profiel
wide flange beam with equal flanges I profiel met gelijke flenzen
wide flange beam with unequal flanges I profiel met ongelijke flenzen
equal legged angle L profiel met gelijke benen
unequal legged angle L profiel met ongelijke benen
equilateral triangle gelijkzijdige driehoek
isosceles triangle gelijkbenige driehoek
triangle driehoek
parallelogram parallellogram
diamond ruit
trapezoid trapezium