Applies To Product(s): AutoPIPE, Version(s): 2004, XM, & V8i Environment: N/A Area: Enhancements Subarea: Original Author: Bentley Technical Support Group The following enhancements have already been requested: Note: if an enhancement has not been added to the program, log an Service request for that enhancement. The more requests logged per an enhancement, the quicker the CAE development team will add that feature to the program. 1. CAE-CR-5848: Add option for above ground continuous support with friction Description: For long runs of pipe with large diameter bends laying on the ground an option of continuous support with friction would alleviate the need for a soils analysis for above grounds piping or closly spaced supports on segmented bends. Avoidance: Option 1: The Buried pipe option can be used to model semi-embedded (debris builds up on the sides of the pipe over time) or non-embedded piping. The difficulty is calculating a transverse horizontal (lateral) and longitudinal soil stiffness. a) The vertical up soil stiffness K1, P1 and K2 can be taken as 0. b) The transverse horizontal K1 and P1 is usually taken as low values. Higher if semi-embedded pipe is anticipated. c) Transverse vertical down K1 and p1 can be calculated as non-zero with H=0 (e.g. equation D-15 in the appendices under the PIPE-SOIL help files under Example Systems). d) The longitudinal K1 and P1 would go to zero with Z=0 but there may be an alternative equation in some textbook which would calculate a non-zero longitudinal K1 and P1 although I suspect it would be a low value since only line contact of soil with the pipe is assumed. You may wish to enter some non-zero K1 and P1 values to evaluate the longitudinal frictional stiffness effect back on the pipe system. It is recommend to set all final stiffness, K2 = 0.1 lb/in/ft (0.006Kg/m/mm) to avoid convergence problems. Option2: Using the equations for modeling a wide mitered bend, without calling it a wide miter, you can calculate a series of partial bends. The difficulty here is calculating all the tangent offset points and you may have to adjust the lengths slightly to get the bends to fit (see Help/Contents/Modeling Approaches/Modeling Approaches/Bends/Miter Bends). You would be able to place supports at the tangent and mid points of the partial bends. Depending on how small you wanted to break up the larger bend this could be tedious but possible. Option 3: This is probably the easiest option. The radius of curvature for the bend is so large that the SIF for the bend would be recognized as 1. Rather than create partial bends you can input incremental kinked runs. You would still have to calculate the offsets but wouldn’t have to worry about getting the bends to fit. You could use as many or as little as you would need to stabilize the bend. Both options 2 and 3 have the benefit of your being able to use V-stops and having friction accounted for without having to equate soil stiffnesses to friction factors. Corrected Version: TDB See Also Bentley AutoPIPE External Links Bentley Technical Support KnowledgeBase Bentley LEARN Server Comments or Corrections? Bentley's Technical Support Group requests that you please submit any comments you have on this Wiki article to the "Comments" area below. THANK YOU!
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