Soil Friction
Soil Friction
(OP)
Dear Frineds
I'm not a civil eng. and I have a basic question:
Suppose two same material and density pipes:
1- A 50 meters carbon steel pipe on 5 steel pipe support.
2- A 50 meters carbon steel pipe on the dry ground(not buried).
which of them does need greater force for moving?
I'm not a civil eng. and I have a basic question:
Suppose two same material and density pipes:
1- A 50 meters carbon steel pipe on 5 steel pipe support.
2- A 50 meters carbon steel pipe on the dry ground(not buried).
which of them does need greater force for moving?





RE: Soil Friction
Mike McCann
MMC Engineering
http://mmcengineering.tripod.com
RE: Soil Friction
Does friction coefficient depend on soil compaction(proctor number)?
RE: Soil Friction
Yes the coefficient will depend, to a greater or lesser extent, on soil type.
Mike Lambert
RE: Soil Friction
Pipe material and pipe envelope backfill material would be determining factors for the inteface friction angle. Research organizations such as DIPRA have publised values for this.
RE: Soil Friction
RE: Soil Friction
Suppose that the pipe movement is due to thermal expansion of the pipe.
RE: Soil Friction
Pipe thrust results at pipe bends, valves, reducers and line stops for pressure pipes. These forces need to be calculated and restrained by the appropriate method. This is why pipeline designer ask questions like: "what is coffecient of friction for the soil/pipe interface".
In the water pipeline design world we use restrained joint pipelines or thrust blocks to resist thrust forces. Sometimes, we need to use batter piles to support the thrust blocks. Thrust forces can be very large depending on the pressure and diameter. Improperly restained pipes can rupture, do lots of damage and result in loss of life. Calculation and design of pipe retraint can get complex due to geometry of multiple bends in a short distance (i.e., become three dimensional problem).