A Manhole Size library contains the acceptable manhole sizes, connection sizes and access sizes that will be used by the manhole autosize calculations. Libraries can be saved as .IDMHSX files so that they can be shared/reused.

By selecting the manhole size library from the pipe sizing criteria form you will be able to edit / create a manhole size library. Simply fill out each of the three tabs with valid data.

The Diameter/Width tab determines how the diameter and width of the junction is sized based on the incoming/outgoing connection. The first column requires the diameter/width of the connection to be entered, the other two columns require the junction diameter/length and width to be inputted. During sizing the connection size will be matched with the entered diameter/length and width in order to size the junction. If no width is specified then any rectangular manhole will be made circular however if a width is specified then circular manholes will be made rectangular.

There is an additional sizing option on this tab, which allows a connection size to be specified that once exceeded will increase the junction diameter/length and width by the inputted amount, this allows for the junction to always be sized bigger than the connection.

The Depth tab determines how the diameter and width of the junction is sized based on the junction depth. The first column requires the depths of the junction to be entered, the other two columns require the junction diameter/length and width to be inputted. During sizing the depth of the junction will be matched with the entered diameter/length and width in order to size the junction.

During sizing the two tabs results are compared and the biggest diameter and width of the two are selected.

The Access tab only applies when an offset is required. In this tab the ladder protrusion is calculated based on the junction depth. The first column requires the depth of the junction to be entered and the other column requires the ladder protrusion amount. Then if the offset requirements have been met the depth of the junction will be matched against the required ladder protrusion and used in the offset calculation.

Also available on the Access tab are the Landing Width and Benching Width.  These dictate how much space is available on either side of the junction when split by the incoming and outgoing connections.  Landing width is the minimum width measured from the edge of the ladder to the incoming/outgoing connection meeting point.  Benching width is the minimum width measured from the incoming/outgoing connection meeting point to the edge of the junction.


Note

The first column of each tab must be entered in ascending order and must each be unique. Additionally there is validation to ensure both of these conditions are enforced as well as validation to stop invalid data being entered

The New button clears the current manhole size library.

The Open button allows the import of .IDMHSX files or the importing of excel and txt/csv files using the universal importer.

The Save button exports the current library to .IDMHSX.

The Default button loads the standard manhole size library converted to the relevant units.