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ODOT is looking at adopting the Wisconsin portable barrier that passed MASH TL-3 for freestanding and anchored in concrete (TRP-03-386-19). The lifting/drainage slot shown on the Midwest detail with in the referenced report is 4" deep and 1' wide, and located between the a2 bar and the center anchor pocket. A supplier is asking if they can modify the size (due to simplifying constructability/forming) and relocate the between the first set of vertical bars and the a2 (to make for easier handling). I attached a picture of this showing the Midwest detail on top and the supplier's detail below. Having the slots so close to the center apparently causes the barrier to sometimes teeter when being lifted. Also, they say the 1'-4" tapered to 1-6" makes for easier lifting, and allows the precast section to be released from the form much easier after pouring, versus the straight edge. Will the alteration and size and location of these slots impact the performance of the barrier?

We do not see any issues with revision of the slots as shown. Nebraska DOT has previous modifed the drainage slots to incorporate four 12" long slots in the segment as shown in the attached file. 

The proposed modification would provide similar drainage cavity space. The NDOT barrier has been tested to MASH TL-3. 

Thanks!