Manhole statics (new construction)

Structural analysis of manholes: Statics for earth-jacketed shaft structures

iro 2023: IngSoft at the Oldenburg Pipe Forum

From 30 to 31 March 2023, IngSoft will be attending the 35th Oldenburg Pipe Forum


Worksheet DWA-A 127-1 "Fundamentals" (with restrictions) published

Worksheet DWA-A 127-1 - Structural analysis of drainage systems - Part 1: Fundamentals - December 2022 in the DWA Shop


Practical examples for professionals at "Look at the pipes"

Detailed practical examples - from large network operators to small municipalities - show different possibilities and measures for network maintenance.


Manhole calculation module

The Manhole calculation module is based on knowledge from pipe statics with engineering extensions and enables you to examine circular manholes from a structural point of view. The program for shaft statics performs the verifications in several design sections of the casing at the base and head of the manhole as well as at openings.

Boundary conditions such as working space, openings, nozzles and installations are included in the radial and axial considerations. If necessary, interaction verifications are carried out at prominent points. Plastic and coiled pipes can be mapped.

The following are listed as loads next to and on the shaft

  • Earth and traffic loads
  • Casing friction
  • Groundwater (buoyancy check)

Lid (cover) designs are

  • Concrete cone
  • Overlying lid or
  • Separately supported lid
  • Flat roof, if necessary with stiffening ribs/struts
  • Direct load input
  • Manufacturer-specific special designs

Bottom designs are

  • Shaft bottom with and without base plate
  • Shaft bottom with and without reinforced concrete foundation
  • Weight block for buoyancy control
  • Overhang
  • Sealing against pressing water

For standard covers and bottom plates, the software determines the required reinforcement.

Get to know the Manhole module?

The calculation module is part of the demo version of IngSoft EasyPipe.

Request a non-binding demo version now!

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Image: ingsoft-easypipe-shaft-expression-sketch-lid-bottom.png
Image: ingsoft-easypipe-shaft-expression-floor-tension.png
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Insights into the calculation module for shafts

Manhole convinces with its convenient user interface. System sketches in input and printout support you in creating/checking your shaft statics. The graphical progression of various actions (loads) over the installation depth simplifies the selection of possible load combinations.

Special features of the static calculation of buried shafts, such as the course of the earth pressure or the (horizontal) soil stresses, are clearly illustrated.

With Manhole, you can complete the shaft statics quickly and elegantly.

Click on a picture for further explanation.
(Screenshots are in German, software is available English.)

Focus shaft pipe

The static calculation of an underground manhole focuses on the essential component: the shaft pipe itself. Our calculation module Manhole for IngSoft EasyPipe expands the scope and additionally measures cover plates and bottom plates or manhole foundations. If desired, it takes into account openings and nozzles for inlets and outlets.

Manhole automatically forms the relevant cases from a large number of possible combinations of actions. As the user, you control the printout: you decide whether the programme outputs all loads or only relevant superpositions.

If time-dependent materials are to be examined, the shaft software offers two ways:

  • Weighting of the material parameters depending on the proportion of permanent and variable actions ("state of the art")
  • Verification separately for short-term and long-term loads with final superposition

Our research showed that "weighting" is not always "on the safe side". With Manhole you cover both possibilities.

Set of rules in progress

At the DWA, a working group deals with the static calculation of manholes. We are an active member of this committee.