Pipe Connection represents a pipe with a circular cross section. The flow routing through a Pipe Connection is described in
Analysis of Junctions and Connections.
Parameters to specify:
Length, Slope, either Manning's n or Colebrook-White Roughness, Diameter/Base Width, see CConnections Inputs.
Upstream (US) Cover Elevation, Upstream Invert Elevation, Downstream (DS) Cover Elevation, Downstream Invert Elevation, Culvert Type and Culvert Entrance.
Entering a value for Manning's n or Colebrook-White Roughness will clear the value of the other. Manning's n is used by default.
If the Slope or Downstream Invert Elevation are changed by the user the other variable will be updated to match the slope.
If the Culvert Type is updated, the available Culvert Entrances are updated.
Automatic Setting of Elevations
Where possible connection elevations are automatically set from
Surface Data data, existing
Stormwater Controls - SWC and existing
Junctions. This is done following the rules below but can be overruled by the user. Where elevations have been overruled by the user or by the Network Design procedure the values will be shown in red to indicate they are no longer following the rules below and will not be automatically updated.
US Cover Elevation
- If the US coordinate is on a surface then set the US Cover Elevation to be the surface Elevation at the US coordinate (in the case of a Stormwater Control this may be at the location of an Inlet or Outlet).
- If the US coordinate is not on a surface (either a surface is not loaded or the US coordinate is not on a surface) then set the US Cover Elevation to the Cover Elevation of the upstream Manhole or the Exceedance Elevation of the upstream Stormwater Control.
DS Cover Elevation
- If the DS coordinate is on a surface then set the DS Cover Elevation to be the surface Elevation value at the DS coordinate (in the case of a Stormwater Control this may be at the location of an Inlet or Outlet).
- If the DS coordinate is not on a surface (either a surface is not loaded or the DS coordinate is not on a surface) then set the DSCL to the Cover Elevation to the Cover Elevation of the downstream Manhole or the Exceedance Elevation of the downstream Stormwater Control.
US Invert Elevation
- If the US item is a Simple Junction then the US Invert Elevation = US Cover Elevation –
Network Design Min Cover Depth – pipe Diameter.
- If the US item is not a Simple Junction then the US Invert Elevation = the Invert Elevation of the upstream Manhole or the Base Elevation of the upstream Stormwater Control.
- If the Stormwater Control has an outlet that is not free discharge then the outlet level is used instead.
DS Invert Elevation
- If the DS item is a Simple Junction then the DS Invert Elevation = DS Cover Elevation –
Network Design Min Cover Depth – pipe Diameter.
- If the DS item is not a Simple Junction then the DS Invert Elevation = the Invert Elevation of the downstream Manhole or the Base Elevation of the downstream Stormwater Control.