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Several states have made inquiries regarding alternative anchors for the F-shape barrier bolt-through tied-down. The original design was tested with 1.125" diameter A307 threaded rod that was epoxied 12" into the concrete apron at MwRSF in order to develop the full-capacity of the rod.

Figure 5 shows a list of anchors that were compared with the anchor used in the original bolt-through tie-down design. The listed anchors compare different diameters and grades with the highlighted original anchor. The criteria for selecting an alternative anchor would be that any alternative anchor must have equal or greater bending and shear capacities that the original anchor. In addition, MwRSF would recommend that the alternative anchor have similar or better ductility to Grade 5 threaded rod.

It should also be noted that the use of alternative anchors is only allowable if the anchor capacity can be sufficiently developed. For configurations where the state bolts the anchors through the deck, this should not be an issue. However, states that wish to epoxy the threaded rods into the concrete surface must insure that the epoxy and embedment depth are sufficient to develop loads equivalent or higher than the capacity of the original tested anchor.