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Median barriers in Indiana are almost always constructed by slip forming in order to speed up construction and reduce costs.  When light poles are mounted to the top of median barriers, Contractors will often lower the base of the light pole such that the tops of the anchor bolts are below the typical top surface of the barrier, see picture in attached PDF.  This is done to prevent the slip forming machine from running into the anchor bolts.  Without this modification of the INDOT Standards, the slip forming operation has to be terminated at the light poles and those locations are required to be hand formed and poured after the remaining barrier has been slip formed.  It appears to us that the current practice, as shown in the attached PDF, has the potential of creating a snagging hazard at the light poles, since a nearly vertical face is formed in the barrier immediately adjacent to the light poles.  Just an FYI our light poles are typically spaced somewhere around ever 250 ft.  Our questions are:

• Does the current practice of forming a very short block out create an unacceptable risk of snagging?  If so, our second question is;


• Would the overall risk be reduced to an acceptable level if the length of the block out was increased enough to allow for a 6h:1v top slope on the barrier adjacent to the light poles, see the attached PDF?  This should minimize the risk of snagging, but also introduces a short length of barrier that is less than the design height. 

We would appreciate any thoughts on this matter.  Thank you

I have some thoughts on this.

1. The current installation has a couple of snag hazards. One is the luminaire pole itself and the other is the notch or block out. Using a more gradual slope would tend to reduce the notch snag hazard, but as you noted, it would lower the effective barrier height. This may not be desirable either.
2. We can envision a couple of potential alternative solutions.
   1. First, to eliminate the potential for snag on the pole, one could invert your current installation and install the pole on an elevated island. This would move the base of the pole high enough to limit the potential for passenger vehicle snag on it. One would want to utilize a 6:1 vertical taper and the height of the island would likely need to be 48” or more to reduce the potential for vehicle interaction with the pole. This may not help with you slip-forming and anchor bolt interference issue.
   2. Another option would be a steel plate bolted over the notch. See sketch. This could be installed over the notch to eliminate snag on the notch. There is still the potential for snag on the pole in this scenario.

These are some quick thoughts. Let me know if you need anything else.