Precast Parking Garage Topping Slab Special Admixtures / Sealers

[MJC6125]

I'm working on a precast parking garage with a cast-in-place topping slab applied over the precast double tees. I found the PCI Parking Structure Manual which has some good information on durability considerations including a geographical zone map and table shown below. For reference, this project is in Zone III. I have a couple questions for people who have specified topping slabs like this in the past.

1. Do you typically require any special admixtures in the cast-in-place topping slab? Like a corrosion inhibitor or an integral watertight admixture? As far as I could find, these are not required per code, but I'd like to know if there is any industry standards to require them.

2. Do you typically require a sealer product be applied on all floors and roofs of the parking garage like the PCI manual calls for in the table below?

3. Do you typically require a traffic coating membrane on any of the parking deck surfaces? It sounds like this is recommended over occupied spaces, but I don't think I necessarily have that on my project.

 

[cliff234]

Most of our precast garages are in Zone 3. We follow the recommendations in PCI Table 3-1. Furthermore, we specify the inclusion of 4 pounds / cy of macro fiber fiber reinforcing (to help restrain the growth of cracks) in the topping. We specify a traffic bearing membrane in parking garage framing above occupied spaces for all parking garage framing systems – not just precast.