What is the status of the DWA codes for the structural analysis of underground pipes in September 2026? – An overview.
Introduction
With the IngSoft EasyPipe software and our engineering services, which include structural analysis, we are deeply rooted in the industry. In the field of the IngSoft EasyPipe software we
- respond to enquiries from our users that go beyond the use of the programme
- interpret DWA regulations, DIN standards and Eurocodes
With verifiable structural calculations
- we solve complex problems relating to the structural analysis of pipes and shafts (manholes)
- we take responsibility for structural design
- we regularly demonstrate our expertise
On the committees of
- DWA
- DIN/CEN and
- BUNDESVERBAND GRABENLOS
we play an active role and help shape the regulations. Through comments or objections, we highlight any ambiguities or contradictions. In the run-up to the programming phase, we act as voluntary quality assurance staff.
Research questions
This post answers a number of possible questions.
Is the ATV-DVWK-A 127:2000 worksheet still valid?
Yes. Its announced successor, the DWA-A 127-2 working paper, has been published as a draft. The working group is considering the comments submitted by objectors.
Has the DWA-A 127-2 worksheet already been introduced?
No. The official version has not yet been published. As long as the regulations are published only in draft form, that is, as a ‘yellow print’, worksheet ATV-DVWK-A 127 remains binding.
What is the number of load cycles used for railway live loads in fatigue analysis?
The state of the art is load model 71 (LM71), with 1×10⁸ load cycles. An exception is made for steel pipes with a cover depth of over 1.5 metres: in this case, dynamic verification for 5×10⁶ cycles is sufficient. For further details, see TM4-2019 from DB Netz AG; here is a direct link to the PDF.
What is the current load model for road traffic: SLW60 or LM1?
Whether it is a heavy-duty vehicle or a load model, both have their roots in bridge construction. According to ATV-DVWK-A 127, the SLW60 is established as the ‘classic’ choice for trench laying. Since 2014, pipe jacking, manhole construction and rehabilitation/lining have relied on Load Model 1 (LM1). With the publication of DWA-A 127-11 as a white paper, the SLW60 is being replaced by Pipe Load Model 1, or R-LM1 (German: Rohr-Lastmodell) for short.
How will the DWA proceed with Parts 11 and 12?
Both worksheets were removed from worksheet DWA-A 127-1 because it was not possible or desirable to commit to publishing it as a white paper. Part -11 deals with road traffic loads and the associated fatigue analysis; Part -12 deals with partial safety factors relating to materials. Following their publication as white papers, both sets of guidelines are to be incorporated into Part 1: Fundamentals in due course.
The following table shows the current status of the DWA regulations.
Regulatory frameworks, as at September 2026
| Set of rules | Contents | Date of issue | Type | Valid? | Comment |
|---|---|---|---|---|---|
| ATV-DVWK-A 127 | Trench installation, open cut, new build | 2000-08 | Final | Yes | Tried and tested, well-established |
| DWA-A 127-1 | Basics | 2022-12 | Final | Yes | |
| DWA-A 127-2 | Solid-wall pipes in open cut | 2024-08 | Draft | No | Processed by the working group |
| DWA-M 127-3 | Profiled plastic pipes in open cut | --- | --- | No | First edition currently being prepared, linked to -2 |
| DWA-M 127-4 | Cylindrical, underground manholes | --- | --- | No | First edition currently being prepared |
| DWA-A 127-5 | Pipe jacking | --- | --- | No | Renaming of the current DWA-A 161 |
| DWA-A 127-6 | Renovation using the lining and relining method | --- | --- | No | Renaming of the current DWA-A 143-2 standard; currently being drafted |
| DWA-A 127-10 | Material properties | 2020-09 | Final | Yes | |
| DWA-A 127-11 | Road traffic loads | 2025-09 | Draft | No | Processed by the working group; incorporated into -1 |
| DWA-A 127-12 | Partial safety factors for materials | 2026-03 | Draft | No | Processed by the working group; incorporated into -1 |
The current working instructions and information sheets have been incorporated into IngSoft EasyPipe.
Load models
The number of load cycles specified in the table is generally based on a design life of 50 years.
| Type | Cover depth | Load cycle*) | Valid? | Set of rules | Comment |
|---|---|---|---|---|---|
| Road: SLW60, heavy goods vehicle | from 0,5m | 2x10^6 | Yes | ATV-DVWK-A 127 | Fading away |
| Road: Load Model 1 (LM1) according to EC | from 1,0m | 2x10^6 | Yes | DWA-A 161, DWA-A 143-2 | 120kN or 150kN wheel load |
| Street: Pipe Load Model 1, R-LM1 | from 0,5m | 2x10^6 | No | DWA-A 127-11, planned: all in future | Simplified approach |
| Railway: UIC71 | from 1,5m | 2x10^6 | No | ATV-DVWK-A 127 | Fading away, superseded by LM71 |
| Railway: Load model 71 (LM71) in accordance with EC | from 1,1m | 1x0^8 | Yes | DWA-A 161, DWA-A 143-2, planned: all in future | Special feature of steel pipes – see below |
| Aircraft: Design aircraft, e.g. BFZ750 | from 1m | 2x10^6 | Yes | Virtually all | Appendix to DWA-A 127-1 |
*) The number of load cycles to be demonstrated in the ‘verification against non-predominantly static loading’, often referred to in common parlance as ‘dynamic proof’ or ‘fatigue verification’
Steel pipes
With the LM71 railway traffic load model, the DWA regulations replaced the previous UIC71 load model for the first time in 2014, following the publication of the white paper on DWA-A 161 / DVGW GW 312 (pipe jacking). The main changes are:
Changed designation (LM instead of UIC) whilst retaining the same number: 71
- Cover height: UIC: from 1.5 m; LM: from 1.1 m
- Impact factor: max. 1.40 for UIC, max. 1.67 for LM
- Number of load cycles in fatigue analysis: 2×10⁶ for UIC, 1×10⁸ for LM
For steel pipes laid beneath Deutsche Bahn tracks, the DB Netz AG ‘Technical Document’ TM4-2019 (PDF), which is freely available online, also applies.
- 1×10⁸ cycles must be demonstrated for cover depths (from 1.10 m) up to 1.50 m
- A fatigue life of 5×10⁶ cycles must be demonstrated for cover depths from 1.50 m
- At 5.5 m, the ‘internal pressure zone’ ends; for greater depths, a fatigue analysis is not usually required
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