CALCS PROC051
OPEN STIFFENERS, BS5400

NOTATION

bstiffener pitch
tthickness, plate
lsspan, stifener, between supports
dsdepth, stiffener
Tsthickness, stiffener
tsothickness, stiffener outstand (flange)
bswidth, stiffener flange (2xbso for tee)
bsowidth, stiffener outstand
Asarea, stiffener
Ipsinertia, polar, stiffener
Jstorsional constant, stiffener
rysradius of giration, stiffener, about own centroid
Fcalc coefficient
alphacalc coefficient
mcalc coefficient
kcalc coefficient

APPLICATION

stiffened flat plates

OUTPUT

acceptance of geometric aspect ratios

SEE ALSO

PROC031

THEORY

BS5400:PT3:APPENDIXC:1982

GUIDANCE

As, Ips & Js are for stiffener only without plate contribution

INPUT FORMAT

LET Nk=:Nm=:b=:t=:ls=:ds=:Ts=:tso=:bs=:As=:Ips=:Js=:bso=:Fr=3.55:PROC051

EXAMPLE

Call Statement

LET Nk=1:Nm=1:b=59.7:t=.97:ls=563:ds=40:Ts=1.1:tso=1.3:bs=28:bso=13:As=Ts*(bso+bs):Ips=Ts*(bs^3/3+bso*bs^2):Js=17.75:Fr=3.55:PROC051

Output

PROC051 BS5400, PT3, 1982, APPENDIX C open stiffner requirements, Rev 200497
rys= SQR(Ips/As)= 20.67
UF= (ds/Ts)/(1.7*SQR(E(Nm)/(2*Fy(Nm))))= 1.2441.244
K1= tso/Ts= 1.182
K2= bs/ds= 0.7
F1= (PI^2/12)*((K1^3*K2^3+4)/(4+K1*K2^3+12*K1*K2))= 0.262
F2= PI^2*((K1*K2^3)/(4+K1*K2^3+12*K1*K2))= 0.2791
F3= 1.54*((K1^3*K2+1)/(4+K1*K2^3+12*K1*K2))= 0.2316
alpha1= b*t*Ts^2/Ips= 3.638E-3
alpha2= (b*t/As)*(t/b)^2*(Ts^4/(ds^2*rys^2))= 7.263E-10
alpha3= (b*t/As)*(Js/Ips)*(Ts^4/(ds^2*rys^2))= 2.536E-9
m= (SQR(alpha1^2+40*alpha2-4*alpha3)-alpha1)/50= 5.196E-8
m= (Ts/ls)^2= 3.817E-6
k1= m*(F1+F2*(ds/Ts)^2)= 1.41E-3
k2= 2.25*Fy(Nm)/E(Nm)= 3.804E-3
k1!
UF= (ds/Ts)/SQR(4*F3*Fy(Nm)/((k2-k1)*(4*Fy(Nm))))= 3.6973.697
Additional check for angle or tee stiffner
UF= 10/((bso/tso)*SQR(Fy(Nm)/Fr))= 1.0071.007
END051