Construction & Contractors/direct reading rod


Can you use a direct reading rod with a rotary laser set to slope to in install storm sewer pipe?

This isn't my area of specialty, but from what I've seen most people set their lasers to horizontal and just figure the slope of the pipe off the rod readings, I guess because it's more accurate to level the laser and, if you think about it, the angle you get on the pipe will only be the same as the maximum slope of the laser plane if the laser is sitting right over the pipe.  If the laser is off to the side, the slope will be less due to the horizontal offset and you'd have to figure the difference using trigonometry.  Plus it is usually harder to get an accurate slope as opposed to just leveling the unit.  

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Robert Cummings, P.E.


I can answer questions related to rock blasting, rock and soil excavation (such as tunnels and highway cuts), stability of such excavations, and foundations in rock and soil. I can also answer questions related to geology and mining.


30+ years as a geotechnical engineer and minerals engineer. Active consulting practice in rock blasting, geotechnical engineering, and rock mechanics for mining and heavy construction.

Society of Mining Engineers, Deep Foundations Institute, Association of Engineering Geologists, and International Society of Explosives Engineers.

Mining Engineering, AEG Bulletin.

BS and MS Geological Engineering

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