Have any of you run through the calculations for the shear capacity of an anchor bolt at the top of a CMU wall using section 2.1.4.2.3 of ACI 530-5. This is a situation where for transverse loads, the side distance is less than 12 bolt diameters, so you have to discount the shear capacity of the masonry.
I was checking the capacity of an anchor bolt to plate connection, but increasing the bolt diameter actually reduced the capacity. There is an interpolation requirement based on side distance that actually ends up penalizing you for increasing the bolt size. This occurs because the allowable capacity is taken as the maximum capacity times the factor (side distance minus 1”)/(12 bolt diameters minus 1”) and this factor decreases with bolt diameter faster than the maximum capacity increases with bolt diameter. Maybe I’m missing something, but why should you lose capacity when the bolt size goes up. Can I pretend it’s a smaller bolt? Can I use two bolts offset each side of the wall centerline and base the side distance on the far face?
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