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clear
//
P = 200.0 //K The force on the beam
L = 15 //ft - The length of the rod
F_y = 50.0 //ksi
F_a = F_y/(5.0/3) //ksi -AISC MANUAL ,allowable axial stress if axial force is alone
F_b = F_a //Allowable compressive bending stress
M_1 = 600.0 //k-in - The moment acting on the ends of the rod
M_2 = 800.0 //k-in - the moment acting on the other end of teh rod
B_x = 0.264 //in - Extracted from AISC manual
E = 29*(10**3)
A = P/F_a + M_2*B_x/F_b //in2- The minimum area
printf("\n \n The minimum area is %0.2f in^2",A)
//we will select W10x49 section
A_s = 14.4 //in2 - The area of the section
r_min = 2.54 //in The minimum radius
r_x = 4.35 //in
f_a = P/A_s //Ksi- The computed axial stress
f_b = M_2*B_x/A_s //Computed bending stess
C_c = ((2*(%pi**2)*E/F_y)**0.5) //Slenderness ratio L/R
C_s = L*12/r_min // Slenderness ratio L/R of the present situation
if C_s <C_c then
printf("\n The following approch is solvable")
else
printf("\n The caliculation is not possible")
end
F_a_1 = 19.3 //Ksi - AISC lets try this
c_m = 0.6 - 0.4*(-M_1/M_2)
F_e = (12*(%pi**2)*E)/(23*(L*12/r_x)**2)
k = f_a/F_a_1 + c_m*f_b*(1-(f_a/F_e))/F_b //Condition mentioned in AISC
if k>1 then
printf("\n The following W10x49 section is not satisfying our constraints since f_a/F_a_1 + c_m*f_b*(1-(f_a/F_e))/F_b %0.3f >1",k)
else
printf("\n The following W10x49 section is satisfying our constraints since f_a/F_a_1 + c_m*f_b*(1-(f_a/F_e))/F_b %0.3f <1",k)
end
//trail - 2
//Lets take W10 x 60
A_s = 17.6 //in2 - The area of the section
r_min = 2.57 //in The minimum radius
r_x = 4.39 //in
f_a = P/A_s //Ksi- The computed axial stress
f_b = M_2*B_x/A_s //Computed bending stess
C_c = ((2*(%pi**2)*E/F_y)**0.5) //Slenderness ratio L/R
C_s = L*12/r_min // Slenderness ratio L/R of the present situation
if C_s <C_c then
printf("\n The following approch is solvable")
else
printf("\n The caliculation is not possible")
end
F_a_1 = 19.3 //Ksi - AISC lets try this
c_m = 0.6 - 0.4*(-M_1/M_2)
F_e = (12*(%pi**2)*E)/(23*(L*12/r_x)**2)
k = f_a/F_a_1 + c_m*f_b*(1-(f_a/F_e))/F_b //Condition mentioned in AISC
if k>1 then
printf("\n The following W10x49 section is not satisfying our constraints since f_a/F_a_1 + c_m*f_b*(1-(f_a/F_e))/F_b %0.3f >1",k)
else
printf("\n The following W10x49 section is satisfying our constraints since f_a/F_a_1 + c_m*f_b*(1-(f_a/F_e))/F_b %0.3f <1",k)
end
printf("\n small variation due to rounding off errors")
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