Pipe Support Loads There are two main stages in working with pipe support loads. The first stage is while the analyst is developing the model – supports need to be checked to ensure they are not over-constrained, that loads are reasonable, that there is no liftoff etc. The second stage is once the model is complete, the loads need to be processed for structural use/support design. This second task is well handled now with the Pipe-Link/Staad system. The first stage is not well handled by AutoPIPE. Because of this we have developed an external load processor. We create a results *.mdb file, then use an Excel macro to run a database query and load the information into Excel. In Excel we can: • Combine supports where required – commonly Guide + Linestop will act on a single structure • View global and/or local forces • View global and/or local displacements • Filter based on a number of complex criteria – for example Local Direction Forward greater than +50mm or less than -50mm, Local Force Right greater than +50kN or less than -50kN etc • Use conditional formatting with colours to highlight progressively greater loads and displacements so that the user is automatically drawn to areas of high loading or large displacement • Format the data so that it is easily read – for example instead of displaying a value in N of -28647.52, we format it to kN displayed as -28.7 – this makes it much easier to scan and review the results. The limitations in the AutoPIPE grids are: Grid does not hold changes made. Say for example we wish to view local forces and displacements only, so we hide all of the global force/displacement columns (because the local forces & displacements are out to the RHS of the results grid). We examine the results, then make some model changes, re-run the analysis, and go back to the grids, to find that we have to go and hide all the same columns again. The column hiding should be “sticky”. The filters are clunky – compare them to Excel type filters. For supports you would simply have a dropdown filter at the top of the “Type” column that would allow selection/deselection. Similarly with combinations. It might be argued that the functionality is already provided, and therefore no change is required, however the current Type and Combination filters take up a large amount of screen space, and when I am reviewing results I want to see as much as possible on screen. Combining Pipe Support Loads at One Point It would be really helpful to have an options to combine loads where there are two or more supports at one node point. I would envisage that this be implemented by allowing “Groups” to be defined for each node point, and that supports would be automatically assigned to a group (I don’t think you should have to create these). For example the first support at a node is Group 1, the second support at the same node is Group 2, and so on. This would give the user the ability to join together supports as required by the physical arrangement. For example a typical support on a steam system could use a Guide + Line-stop + Spring hanger. The actual grouping of these would depend upon the detail design of the support steelwork. I can think of one configuration where you would put the Guide & Line Stop in Group 1, with the Spring Hanger in Group 2. Alternatively it is also possible that you might want them all in one group. For simplicity all supports entered at a node would default to unique groups e.g. 1st support inserted = guide (assigned to Group 1) 2nd support inserted = line-stop (assigned to Group 2) 3rd support inserted = spring hanger (assigned to Group 3) This means that users who do not wish to use this feature don’t need to do anything or change anything. However users who do want to combine supports could then assign supports to the appropriate group (in the example above, the line-stop would be changed to Group 1). Output reporting would then be by Group at a node, rather than by support at a node. The Group no. would just be another field that appears on the support dialogue box, and defaults to 1 for 1st support, 2 for 2nd support and so on.
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