transverse fiber directions at T= 50K were computed using the finite element analysis

(Tables 2-11 and 2-12). The micro-stresses in the inner and outer face sheets were

calculated using the superposition method described in the previous section.

Table 2-11. Laminate macro-strains used to obtain the micro-stresses in the inner and
 outer face-sheets of the sandwich composite without internal pressure.
 L er 0 SL (10-3) ST(10-3) z(10-3) YLT(10-3) YLZ YTZ
 Layer (10-3) (10-3)


Inter
Facesheet






Core



Outer
Facesheet


45 -0.149
90 -0.0386
-45 -0.226
0 -0.338
-45 -0.224
90 -0.0374
45 -0.152
 -0.337
65 -0.0899
0 -0.296
-65 -0.00858
90 0.00447
-65 -0.00792
0 -0.296
65 -0.0904


-0.227
-0.338
-0.150
-0.0380
-0.151
-0.337
-0.222
-0.0367
-0.203
0.00423
-0.283
-0.296
-0.283
0.00470
-0.0200


-5.43
-5.43
-5.43
-5.43
-5.43
-5.43
-5.43
-5.43
-5.51
-5.51
-5.51
-5.51
-5.51
-5.51
-5.51


-0.299
0.0773
0.299
-0.0748
0.300
0.0723
-0.300
-0.0697
-0.298
0.106
0.162
-0.107
0.161
0.108
-0.300


0.512
0.422
-0.0898
0.296
-0.0965
0.428
0.506
0.283
0.543
-0.1.82
-0.698
0.686
-0.701
-0.188
0.544


-0.0831
0.302
-0.510
-0.425
-0.508
0.289
-0.103
-0.431
-0.452
-0.684
-0.123
-0.185
-0.121
-0.687
-0.463


Table 2-12. Laminate macro-strains used to obtain the micro-stresses in the inner and
 outer face-sheets of the sandwich composite subjected to a pressure of 10 KPa.


L (10-3) 8T(10-3) 8z(10-3) YLT(10-3) YLz(10-3)


Layer


Inter 45 -0.147
Facesheet 90 0.501
 -45 0.412
 0 -0.233
 -45 0.405
 90 0.498
 45 -0.138
Core -0.238
 65 0.303
 0 -0.485
 -O r 65 0.214
Outer
 90 0.421
Facesheet
 -65 0.212
 0 -0.489
 65 0.306


0.419
-0.230
-0.144
0.500
-0.141
-0.236
0.398
0.497
-0.366
0.422
-0.280
-0.487
-0.280
0.421
-0.375


-5.90
-5.90
-5.90
-5.90
-5.89
-5.89
-5.89
-5.89
-5.57
-5.57
-5.57
-5.56
-5.56
-5.56
-5.56


-0.731
-0.563
0.732
0.553
0.734
-0.543
-0.735
0.534
-0.622
-0.115
0.770
0.119
0.774
-0.122
-0.618


3.11
4.81
-3.67
-0.371
-3.64
4.81
3.18
-0.299
5.30
2.36
-3.31
4.75
-3.30
2.39
5.32


YTZ
(103)
-3.69
-0.407
-3.13
-4.81
-3.16
-0.335
-3.62
-4.81
0.118
-4.75
-4.15
2.37
-4.17
-4.75
0.165