Introduction to Aircraft Structural Analysis (Elsevier Aerospace Engineering)

9.7Tension Field Beams 313

Fig.9.13

Calculation of stiffener buckling load.

Fig.9.14

Effect of taper on diagonal tension field beam calculations.

TakingmomentsaboutB,

Wz−FTdcosβ+^12 σttd^2 cos^2 α= 0 (9.40)

SolvingEqs.(9.38),(9.39),and(9.40)forσt,FT,andFB,

σt=

2 W

tdsin2α

(

1 −

2 z

d

tanβ

)

(9.41)

FT=

W

dcosβ

[

z+

dcotα

2

(

1 −

2 z

d

tanβ

)]

(9.42)

FB=

W

dcosβ

[

z−

dcotα

2

(

1 −

2 z

d

tanβ

)]

(9.43)

Equation(9.23)becomes

P=

Wb

d

tanα

(

1 −

2 z

d

tanβ

)

(9.44)