I have two questions about combination factors with internal pressure.
(1) Table 5.5 (a) and (b) show internal pressure acting in the same direction as the external roof pressure, i.e. opposite sign. Does this mean that if the internal pressure acts in the opposite direction, i.e. same sign, then Kc does not need to be applied to internal pressure?
If Kc applies to internal pressure regardless of sign then the diagrams could be made clearer by indicating this, e.g.,
(2) An internal surface shall not be treated as an effective surface if |Cpi| < 0.4.
If I have Cpi=0.4 can I take Cpi=0.399 and then Kc,i=1.0?
(1) Table 5.5 (a) and (b) show internal pressure acting in the same direction as the external roof pressure, i.e. opposite sign. Does this mean that if the internal pressure acts in the opposite direction, i.e. same sign, then Kc does not need to be applied to internal pressure?
If Kc applies to internal pressure regardless of sign then the diagrams could be made clearer by indicating this, e.g.,
(2) An internal surface shall not be treated as an effective surface if |Cpi| < 0.4.
If I have Cpi=0.4 can I take Cpi=0.399 and then Kc,i=1.0?