Concentric vs. Eccentric Manhole Cones 1

[CivilG]

What is the purpose of a eccentric manhole cone versus a concentric manhole cone? When do you use either. Do you use a eccentric cone because steps need to be bolted into a vertical surface for climbing in and out?

Thanks,

 

[gbam]

yes. Also, you can rotate to miss curb lines etc...

 

[MikeHalloran]

Try climbing a ladder that's tilted toward you.


Mike Halloran
Pembroke Pines, FL, USA

 

[dicksewerrat]

Don't put in steps. They rot over time and turn into safety hazards.

Richard A. Cornelius, P.E.

http://WWW.amlinereast.com

 

[beej67]

All the steps I see in manholes are HDPE or similar.

Hydrology, Drainage Analysis, Flood Studies, and Complex Stormwater Litigation for Atlanta and the South East -

http://www.campbellcivil.com

 

[cvg]

some agencies around here do not allow steps on sewer manholes. makes it too easy to avoid following the SWP which requires a fall harness and tripod

 

[cneberly]

Correct. The flat surface allows for placement of a ladder or manhole steps. The ladder is recommended to be frp or stainless steel construction for corrosion resistance.

Chris Eberly, PE

http://www.parkusa.com