2-way shear vs. anchor strength

[Robbiee]

Hello all,
My question is explained in the attached sheet. Thinking of the failure mode being similar in the two cases, i.e. the same concrete block-out, it is not clear to me why the 2-way shear is 3 times the tension capacity of the anchor in this specific case, where f’c is assumed 30MPa (4350 psi). Any input is appreciated. Thanks

 

[bjcure]

I don't recall the answer, but check out some of the threads on ACI App. D. There are a lot of complaints about App. D being very conservative.