zp: distance between the bolt line and the weld line

Hi,

While I am using RAM connection standalone version 11.0.0.177 i found that there is a value called Zp and it is the distance between the bolt line and the weld line but while I am using beam to girder connection this value is taken as the distance between the bolt line and the outer edge of the girder, my question is why this value changed in this case -beam to girder- although it give me wrong values for the moment on the bolts due to eccentrecity zpImage may be NSFW.
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