7. 34 And, Sab 1.0080xl0 8 + 9.874Sxl0 8 l 3.029xl0 7 !_ t2 tl - 1163ab t3 - 1077ab t3 ½ ½ Finally, l.0080xl0 8 + 9 . 874Sxlo 8 1 3.029xl0 7 1 t2 ½ ab 1163 .:2 + .:2 s + 1077 t2 tl If values of t 1 and t 2 are now given, a relation is obtained between t 3 and ab. The determination of t 1 and t 2 will be finalized in Section VII.S; however, if we may assume a given value of 4 cm for both t 1 and t 2 , the curve on Figure 7.11 represents the ab vs t 3 relation. VII.4.S.2: Calculation of Bulkhead Stress - Thickness Relation with Outer Hull Failure: In the event of an outer hull failure the bulkheads will be subjected to a uniform transverse pressure load in addition to the normal applied tension load discussed in the previous paragraph. This situation is similar to that described in Section VII.4.3.2 for the inner hull plate bending condition. I n the present case, however, the bulkhead section dimensions are approximately 20m x Sm. In order to simplify both the analysis and the bulkhead construction, it is proposed that beam columns be used to separate the bulkhead sections into Sm x Sm clamped plates. The minor stiffeners would then be used simply as crack arrestors and would not support the pressure load as in Section VII.4.3.2. It is further assumed that the maximum plate bending stress obtained in this analysis will add linearly to the tension stress determined in Section VII.4.S.l. Referring again to Reference (7.11), pages 42 and 202, we determine the maximum bending moment and maximum bending stress for a Sm x Sm clamped plate under tranverse load P 0 •
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