POHYBOVÉ ÚSTROJÍ - Společnost pro pojivové tkáně

Fig. 4. FE model of the C/C plate Table 4. Stresses in the C/C plate
plane symmetry of the real plates M = 600 The C/C plate
(FE analysis) and the limit bending moment According to the FEM computation, the
at the plane symmetry of the real plates failure of the C/C plate under investigation
M MAX.
The Tsai-Hill strength criterion is usually
used for evaluating composite structures.
was caused by the maximum bending
moment of M MAX = 18400 acting in the
middle of the plate (i.e., at the plane of
However, the criterion requires knowledge symmetry xy). In Fig.4, one quarter of the
of the strengths of a layer in tension, in plate FE mesh is plotted, and several
compression (in the fibre/warp direction nodes, at which a critical stress state can be
and in the perpendicular direction to the expected, are denoted by numbers: i) at the
fibres/warp) and in shear. In our case, the plane of symmetry xy; ii) at the screw hole 1
strength in tension, and in compression, in position close to the plane of symmetry xy.
the warp direction and in the direction Corresponding stresses for these nodes are
perpendicular to the warp were known. listed in Table 4. The node numbered 1784
Hence the maximum stress strength re p re s e n t s t h e m a x i m u m s t re s s
criterion was used. corresponding to the failure bending
Fig. 5. FE model of the C/E plate Table 5. Stresses in the C/E plate
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LOCOMOTOR SYSTEM VOL. 6, 1999, No.2