November 1992 Table of Contents

Problem Clinic Understanding F-Numbers for Floor Flatness and Levelness

We're bidding on a concrete floor job that requires a minimum FF of 20 and a minimum FL of 17. What do these numbers mean and how hard is it going to be to build to these specs? Read more

Problem Clinic Rebar Near Surface Causes Marks in Slab

We just placed a 6-inch-thick slab on grade with #4 rebars spaced at 12 inches on centers each way. The rebars were 1 1/4 inches from the slab surface. The concrete was placed by crane and bucket and had a 5- to 6-inch slump. It was hand-screeded without Read more

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