Slip resistant connection between steel and concrete surface according to Eurocode

[StructuralCivilFEA]

I have a pre-loaded bolt in a connection with steel and concrete - and I wanna make sure this connection is slip resistant (along the red line), meaning it has design slip resistant bolt as seen in formula (3.8a)


In the section below you can see Table 3.7 with different slip factors; are these slip factors valid for steel/concrete connection? They seem like they are for steel/steel surfaces to me, I am not sure what to do to make sure concrete/steel surface pre-loaded bolt connection is slip resistant.


Class of friction classes described:

 

[HTURKAK]

My points based on Eurocodes are ;
- Refer to EN 1993-1-8 caluse 6.2.2 Shear forces , item 6
Cf,d is the coefficient of friction between base plate and grout layer. The following values may be
used:
– for sand-cement mortar Cf,d = 0,20 ;
– for other types of grout the coefficient of friction Cf,d should be determined by testing in
accordance with EN 1990, Annex D;
- The friction depends on minimum compressive load and coeff. of friction. The preloading the anchor bolts will increase the resistance of the shear force transfer by friction but the code is silent for this . My opinion, a minimum preload ( calculated after loses ) could be added compressive load with a partial safety factor say 1.5,

The clause 6.2.8 (Design resistance of column bases with base plates )
(5) One of the following methods should be used to resist the shear force between the base plate and its
support:
– Frictional design resistance at the joint between the base plate and its support.
– The design shear resistance of the anchor bolts.
– The design shear resistance of the surrounding part of the foundation.
In case of , where the horizontal shear force cannot be transmitted through friction between the base plate and the grout, i would prefer shear key.