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FDOT is phasing out the FDOT 415 (Jersey Shape). The existing anchoring plate we use in Florida are not crash tested and FDOT is proposing using the anchoring holes on the F shape to stake the barrier end unit when they are attached to crash cushions or if the barrier is on the trailing end.

1.       I don't have any details on the type of crash cushion you are using, but I am assuming that the design is fixed on the end to some sort of rigid end post or support. The staked PCB transition was not designed with the intent of providing anchorage and support for end mounted crash cushions. There would be concerns if you were planning to use the staked PCB sections in that manner.

2.       There needs to be some care taken when connecting the PCB to the end of the crash cushion. This connection is critical because it must be capable of developing and transferring the necessary shear and tensile loads between two barriers as well as prevent snag at the barrier joint. The transition we tested had nested 12 gauge thrie beam across both sides of the joint. These thrie beam sections were capable of developing shear and tension across the joint as well as preventing snag of the vehicle on the joint. With that in mind, we would recommend that the connection between the crash cushion and the PCB in your detail have similar or greater capacity and be capable of preventing snag across the barrier joint.

3.       On the downstream end of your opposing traffic, your detail shows using the stakes to anchor the downstream end of the barrier. Use of the stakes in this manner to create a downstream anchor has never been tested. There is some concern that impacts on the end barriers may cause barrier rotations and deflections that would promote vehicle instability. Typically, we have recommended extending the downstream end of PCB runs a minimum of 8 segments past the length of need and then flaring the end outside of the clear zone.