...< J M", , M-r Let us first consider modelling with respect to bending moments M t making use of (1.1) (just as for the force P, ). For the external moments with density "'a.CJ rn,C:z;y) (the corresponding mollents per uni t area) the right side of (1.1) is added by the sum -3",a/a~+am:llt3z Let us introduce the salle nondillensional variables as above in (1. 3), and assUJle 0 Besides, let 111 c.~ U); 11I1) _ ""Cf) :l'. o .r,L' In'h(:r f31.1 I (3.1) ""3:0 = M:ro P2. (1r., !lo) I m \10" tI. P!lo Ct .. , y.) I II I.d;r.dlo= 1 Col. Then the equation which we obtain differs from (1.4) only in the naJleS of nondimensional variables at the right side, which, Just as in (1.4), do not depend on h . Let us represent its solution in the following form: IJ: L f Mz. ~ao, e.) +r\~ ..5'J(:x fo) 1 (3.2) Let us determine the potential energy of strain. Acting like in (1.7) we find that its derivative with respect to eo differs from by half of the right side of (3.3) taken without the terms with mollents' derivatives. Keeping in view that M=JM! +M,1 i :: 1'3 L4 Mo = f3L".JM:r:+M~ and using fracture criterion (1.8) we find (3.4) Of course, the ratio between the conponents M~, M II remains constant 1f all the nondimensional var1ables do not change. The same d1Scussion as in section 2 for the dynamical case brings to a conclusion that relationship (3.4) remams as a factor of some function of nondimensional t1me to. 4. HORIZONTAL FORCE AND K>DELLING IN THE GENERAL CASE Horizontal force act1ng upon the central plane of a plate may produce an effect on its flexure only due to cham forces Tx , T '1' :; However, in case of local extemal load its influence quickly fades with distance, it is not very important for plate flexure. Nevertheless its...