deflection in stiffened plate under pressure

[fourwheelinyota]

can anyone point me in the direction of calcs for the deflection of a stiffened plate under normal vacuum.


thanks

scott

 

[pmkPE]

Formulas for Stress and Strain; Roark and Young

 

[flamby]

The plate acts as flange and the stiffener is the web of a T-Beam. Look in your code to find out how much width of the plate acts as flange and then find out the sectional properties of Tee. Rest of the cals are simple.

 

[fourwheelinyota]

It was more difficult than that. here is the equation that works out



____________”thick plate __________#of stiffeners ___________” per stiffener

Ap = cross sectional area of plate within distance b
As = cross sectional area of stiffeners
B = distance between stiffeners
D = distance between center of gravity of panel and that of the stiffener
T = thickness of panel
Is = moment of Inertia of stiffener
Wi = width of stiffener (for inertia of stiffener)
E = modulus of elasticity (28500000 for 304ss)
I = moment of inertia of whole panel stiffened
L = length of panel

Cp = As d + t = distance form neutral axis of whole section to outer fiber of plate
As + Ap 2
Qp = Mmax Cp = maximum stress in outer fibers if panel
I
Mmax = p b L^2
8
Deflection = 5 p b L^4
384 E I
Moment of inertia Wi(T of stiffener)^3
12
Ap =_____________________
As = _____________________
B = ______________________
D = ______________________
T = ______________________
Is = ______________________
L = _______________________
E = _______________________

________________________________________________________________________
I = Is + Ap T^2 + As Ap D^2
12 As + Ap



Max Stress (Qp) = ________________________________________________________________________________________________________________________________________________

Deflection of Stiffened Panel
________________________________________________________________________________________________________________________________________________Max Deflection = _______________________