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The details for PCB anchored in concrete show a connection pin with a 5/8" diameter hole at 1 1/2" from the bottom of the pin. Is a retainer bolt and nut required here to restrain vertical movement of the connection pin (during an impact event)? The bill of materials do not seem to include one, and I do not see it in the images from the crash test. There does not appear to be a hole in the connection pin for the freestanding version from TTI's Test Report No. 607911-1&2. ODOT is adding this shape of PCB to our standard drawing, and we were not sure if we should require a retainer bolt, exclude it, or leave it to the discretion of the contractor?

The connection pin does have a hole for a retention  bolt in that system. However, the retention bolt is not required for the free-standing or concrete tie-down anchors through the vertical holes in the face of the barrier segment. Both of those systems were tested with an unconstrained pin. 

The hole has been retained in the design for two reasons. First, MwRSF previuously developed a steel strap anchorage for that PCB that connected to directly to the connection pin. That system requires the constraint bolt in the pin. Additionally, the constraining pin is preferred by some states as a vandalism deterent.