Read about START-PROF pipe stress analysis software
Input data can be copied using the
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icon and inserted into any other Start-Elements analysis by using the 
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that file.
Pipe strength against the surface load is calculated using the method described here.
Property |
Description |
External diameter, Da |
External pipe diameter, D |
Pipe wall thickness, S |
Nominal wall thickness |
Mill tolerance |
Mill tolerance at the time of production. More... |
Corrosion and wear allowance |
Corrosion and wear allowance (working mill tolerance) for wall thickness. More... |
External casing diameter, Dc |
External insulation casing diameter. If insulation is absent, set as 0 |
Casing thickness, SC |
Insulation casing thickness |
Weld bending quality factor |
Set based on standards. Can be calculated automatically
by pressing |
Ambient temperature |
Average wall (metal) temperature at the time when pipe segments become a single joined structure. More... |
Operation temperature |
Operation temperature in operation state. More... |
Depth, Z |
Depth (distance from soil surface to pipe axis) |
Insulation weight |
Insulation uniform weight. More... |
Product weight |
Product uniform weight. More... |
Backfill soil number |
Trench soil number, can be selected from the soil database (see appendix 1 below) |
Base soil number |
Base (undisturbed) soil number, can be selected from the soil database. |
Steel grade |
Pipe material from the materials database |
Operation pressure, P |
Operation pressure in operation state. Set for all standards except SNIP 2.05.06-85. More... |
Working pressure, Pwork |
Working pressure (based on standards). Set when analyzing with SNIP 2.05.06-85. More... |
Insulation type |
Insulation type: armopenobeton, polymer, polyurethane, other |
The additional vertical load for each point of the pipe insulation casing perimeter from the concentrated force, applied on the ground surface can be obtained from Bousinnesq equation
The additional vertical load for each point of the pipe insulation casing perimeter from the infinite length uniform load across the pipe, applied on the ground surface can be obtained using the equation
START-PROF apply two concentrated loads P at the distance L and one uniform load q, and calculate the sum of soil pressure on each point of the pipe finite element model surface around the upper half of the pipe. Also the pressure from the soil weight and pipe internal pressure are applied to the finite element model. After that the nonlinear finite element analysis is done the same way as mentioned above.
Two options of concentrated forces application are considered. The first option is the application of the two forces at the distance L/2 from the pipe axis. And the second option is when first force is right above the pipe axis. The worst pipe and insulation stresses are calculated and taken into account.
See also Polyurethane (PUR) Insulation Stress Analysis
Operating Stress - ring bending stress in the pipe wall
Allowable Stress - allowable stress according the selected code
Ovalization
Dmax, Dmin - maximum and minimum diameter of ovalized cross section of the pipe, Dн - pipe outer diameter
Deflection - ring deflection
Pipe. Buried> Pipe Strength against Surface Load
.