Reply To: laminated composite stiffened plate/stiffened panels

[lidianne.pinto]

Dear Govindan,

 

When MPC is considered, the buckling load changes from 61.958 kN to 64.33 kN for the problem described above.

 

When two plates of uniform thickness are stacked  (see the figure below), one with a stacking of [-45 90 45 0 0 45 90 -45] and the other with a stacking of [45 0 -45 0 -45 0 45], the load changes from 61.958 kN to 257.46 kN. However, the buckling load of just one plate with a stacking of [-45 90 45 0 0 45 90 -45 45 0 -45 0 -45 0 45] is 464 kN. The analytical solution for this case is 450 kN. 

What could be happening?

I found that when considering a plate stiffened by a trapezoidal geometry without the 'foot', i.e. the flange connecting the stiffener and the skin, the buckling load approaches the load calculated analytically without considering the MPC. However, when considering a stiffener foot, this load diverges even considering MPC. In this case, when not considering MPC the buckling load is 9.5 kN, when considering MPC it is 11.44 kN. Whereas the load obtained analytically is 13.13 kN. The figure below illustrates the case of a plate with stiffener 'foot'.

Thank you,