On site, the maximum winter frost line is between 4-1/2 and 5-feet deep underground. An existing pipeline is currently buried 3.5 deep which is above the aforementioned frost line. A portion of the exiting pipeline needs to be lowered due to new agricultural activity in the area. Therefore, a portion of the exiting pipeline will be replaced with new piping buried deeper below the frost line and then tied in.
Can AutoPIPE model the stress in the existing piping and tie-in piping?
Yes, suggest the following approach:
1. Model the exiting pipeline.
2. Model the new piping with the tie in configuration.
3. Add 2 new soil properties: 1. Soil property above the frost line and 2. Soil property below the frost line.
Note: Sometimes soils freeze so that there is no visible difference between frozen soil and ice. Suggest to consult a Geo-technical engineer's report for site soil properties both above and below the frost line. Otherwise the stress analysis my be unconservative or overly-conservative.
4. Apply soil properties to the pipe as needed. using the frost line as the deciding factor.
5. Analyze the system. and review the results.
Again, realize that the results approximation depend heavily on soil properties specified.
Model Soil Properties with Soil Calculator and Underground Piping
Bentley AutoPIPE