Application guide
UGCalc
Pressures on u/g pipes.
What this tool does
Pressures on u/g pipes. This guide describes the main workflow, key information and stated limits to review when using the tool.
Application version: V38.
Assess a buried service
- Enter pipe geometry, cover depth, soil and bedding assumptions, and the location and size of the surface load.
- Use the Main/Calc inputs to define the load cases and select the pipe behaviour and material route.
- Run the calculation and inspect the stress distribution at pipe level, wall-stress indicators and the code-check summary.
- Review the in-app assumptions and acceptance criteria. Save or export the calculation record if the route offers it.
- Compare the result with the actual installation details and service-owner requirements before accepting the pipe or surcharge arrangement.
Calculation basis
The surcharge stress is estimated using the Boussinesq elastic half-space method. The app provides BS 9295-style checks for flexible pipes and rigid pipes, using its stated assumptions for pipe, bedding and surrounding ground.
Ring and oval figures are indicative pressure indices based on assumed granular bedding. They are not pipe-wall stress analyses and should not be treated as a full soil–pipe interaction model.
Verification
Confirm cover, load footprint, load spread, groundwater, soil stiffness, bedding quality, pipe class and installation conditions. Check the applicable edition and acceptance criteria of BS 9295 and the pipeline owner’s requirements. The app output is a check aid and does not replace a project-specific buried-service design.