shear friction with dynamic load 1

[wildehond]

I am working in South Africa and at a local project have proposed "clamping" on in-situ cast concrete “corbels” on both sides of an existing bridge pier in order to allow temporary jacks to lift the bridge beams for bearing replacement. My concept is for the contractor to cast the new corbels with only nominal dowels into the existing pier’s concrete and then to use stressed dywidag bars right through the corbels + pier to provide the "clamping" force to resist the shear load that the beams will exert. While the reviewers I have presented this to have conceptually agreed to the model, they have left me with 2 problems.
1. I am using an old ACI standard of which I only have the 2 relevant pages for shear friction. (Its probably at least 15 years old.) A trawl through some previous shear friction thread on this forum has allowed me to glean that the “new” ACI section is 318-02 and it defines Vn = Avf*fy*mu. Would somebody be prepared to post a scanned version of the new sections so that I can include it in my formal presentation to the reviewers of my design?
2. During the bearing replacement phase, the clamped corbels will be subjected to “dynamic” loads from the vehicles. Is there any additional “factor of safety” or “dynamic load multiplier” that must be used when using the ACI formula?

 

[WARose]

In an old version of AASHTO I have [17th edition], the coefficient of friction is given (for shear friction transfer in concrete) without regards to whether the load is static or dynamic [Sect. 8.16.6.4]. The coefficients appear to be identical to those in ACI 318 (which tends to be use mainly for static loads).

I think the dynamic coefficient of friction [which does tend to be less] doesn’t come into play until an object overcomes its static coefficient (and ergo is placed into motion).