I have the numbetrs for cemeny oval pipes
12 inch cement oval, Area- .83 Sq. Ft., circum. = 40.19 inches
15 inch cement oval, Area = 1.27 sq. ft.Circum. = 49.64 inches
18 inch cement oval, Area = 1.81 sq. ft. Circum. = 58.21 inches.
These are pipes that look like drain tiles and are 100 plus years old. They tend to deteriorate with a pattern that reflect the compaction effort during the construction of the pipe. The inside of the old pipe takes on a look like a corrugated pipe with a long span from peak to peak. This is the stoke of the machine that made the pipe. I will try to post some drawings of these. These drawings and numbers are courtesy of the City of Mpls., Sewer Maintenance Dept. At least that is what it was called back when I was in charge.
Richard A. Cornelius, P.E.
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