Deltaressystems design and analysis tools

Design of pipeline installation

Pipelines are an important part of the underground infrastructure. They are the lifelines of our modern society. The successful operation of a pipeline system on the long term, however, is largely determined by the quality of the engineering works prior to the installation of the pipeline.

From time immemorial, pipelines have been installed in trenches. After excavation of the trench the pipeline is installed on the bottom of the trench and is subsequently covered by the excavated soil. Since the 1970s, Deltares has been involved in the development and execution of trenchless technologies. Trenchless techniques provide a logical alternative when pipelines need to cross roads, railways, dikes, wetlands, rivers and other structures that have to remain intact. These techniques minimize the impact of installation activities in densely populated and economically sensitive areas.

Previous releases of D-Geo Pipeline were named MDrill. MDrill was one of the first design codes for Horizontal Directional Drilling (HDD). MDrill was de result of years of research. Since the release of the first version in 1995, the design code has regularly been updated with new knowledge. Recently, two modules have been added to take into account the installation of pipelines using micro tunnelling and the installation of pipelines in trenches.

General

The program D-Geo Pipeline provides tools for the design of a pipeline installation in a trench and trenchless installation, using the micro tunnelling technique or the Horizontal Directional Drilling (HDD) technique. D-Geo Pipeline allows the user to minimize the risks during and after installation.

• Geometry and 3D pipeline configuration
  The graphical user interface allows an easy and fast input of the soil layers. The upper soil layers can be designated as load for settlement calculation purposes. The three-dimensional pipeline configuration can be entered by a fast tabular input.
  

• Arching
  In case of trenchless installation, D-Geo Pipeline applies a reduced neutral soil load to incorporate the effect of arching. The amount of reduction depends on the installation method, the depth of the pipeline, diameter and the soil properties.
• Pipe stress analysis for horizontal directional drilling installation
  D-Geo Pipeline calculates the stresses in the pipeline during the installation stages in both axial and tangential direction. In a comprehensive report a stress verification is given for each pipeline material used.
• Advanced calculation of settlements
  Vertical displacement of soil below the pipeline that occurs after installation is an important factor in assessing the stresses in the pipeline. Pipeline settlement may be entered manually if the vertical settlements are available. For more accurate results, D-Geo Pipeline can use the D-Settlement computer program without additional input.
• Advanced pipeline stress analysis
  For advanced pipe stress analyses special programs need to be used. These programs need an advanced set of soil mechanical parameters, provided by D–Geo Pipeline. The programs will generate a complete spring model around the pipeline for further analyses. The soil mechanical parameters provided by D-Geo Pipeline are:
  - neutral, passive and reduced vertical soil load
  - vertical and horizontal modulus of sub grade reaction
  - ultimate vertical and horizontal bearing capacity
  - neutral horizontal soil load
  - vertical displacement
  - maximum axial friction
  - friction displacement.

D-Geo Pipeline comes as a standard module, which can be extended further with other modules to fit two other applications related to pipeline installation:
DGS 05.00 D-Geo Pipeline Standard module (Horizontal Directional Drilling)
DGS 05.01 Micro Tunnelling module
DGS 05.02 Trench module.

Interaction with other Deltares systems tools

D-Geo Pipeline interacts with other Deltares systems tools for settlement analysis, seepage analyses, central project and database storage:

• D-Settlement for analyses and import of settled geometry
• D-Geo Stability for slope stability analysis
• Scia Pipeline for advanced structural analysis of pipeline behaviour.

Support

Deltares Systems tools are supported by Deltares. A group of 70 people in software development ensures continuous research and development. Support is provided by the developers and if necessary by the appropriate Deltares experts. These experts can provide consultancy backup as well.

On-line software (Citrix)

Besides purchased software, Deltares Systems tools are available as an on-line service. The input can be created over the internet. Heavy duty calculation servers at Deltares guarantee quick analysis, while
results are presented on-line. Users can view and print results as well as locally store project files. Once connected, clients will be charged by the hour.