I want to know in details what does the centric force meaning
It's hard to say without some further context. Where did you find this term?
" General Case of Eccentric Axial Loading :
-Consider a straight member subject equal and opposite eccentric forces
-The eccentric force is equivalent to the system of a centric force & two couples "
That's the context
The passage just means that an eccentrically loaded member can have the eccentric load replaced by the same load directed along the axis of the member plus a couple whose magnitude is equal to the product of the original applied force and the distance between the point of application and the central axis of the member.
See this example:
Thank you very much!!
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