Occasional loads can be included in any piping model for analysis. Some common static occasional load options are Wind, Snow and Static Earthquake. Let's review these options:
For Wind loads, users have the option to use UBC or ASCE-7 (1998, 2002, 2010 or 2016) codes. With one of these options, the user can enter some inputs and the wind profile will be created for you. If none of these codes apply, the user also has the option to choose “Profile.” With this option, you can input your user wind profile, defining how the pressure changes with height.
To define the Wind load case, click on Load > Wind.
Fill out the inputs in the top section of the Wind dialog box. Then click New to create a new Wind load case.
If you want to define a User Profile, select the specific wind profile you want to update (W1) and click on Modify.
In the Wind Profile dialog, the user wind profile can be created.
If you would prefer to use a wind code, select from the Type pull down menu for that specific Wind load case.
After choosing a code, select the row of the Wind load being defined (W1) and then click Modify.
In the next dialog box, enter all the inputs and click OK. This dialog will have different required inputs for each code. From these inputs, a wind profile is created.
Snow loads are basically applied as a distributed load on a segment basis. You can apply it as weight per length, weight per area or density.
To define the Snow load case, select Load > Snow.
Choose your Method and input your load. Then leave the checkbox checked on if you want the snow load applied to all segments. If you only want the snow load applied to a part of your model, uncheck the checkbox.
In the Review Component Data Input Grid, under the Segment tab, you can choose which segments you want the Snow load applied to. The same can be done for the Wind load.
Static Earthquake Loads
For Static Earthquake loads, you can choose from ALA (ASCE 2002), ASCE 2010, ASCE 2016, Chinese GB50011 – 2001 and Mexican CFE 2008 codes. You can also create a User profile where you can input the x, y and z components of your earthquake loads, using seismic accelerations as a factor of g. Again, if you choose from one of the codes, you have to enter some inputs and then the seismic accelerations will be calculated for you.
To define the Static Earthquake load case, select Load >Static Earthquake.
Create a Static Earthquake load case by selecting New. If you are using the User option, simply enter in your earthquake g-load values.
If you prefer to use a Seismic Code, select from the pull down options.
After choosing a code, select the row of the Static Earthquake load being defined (E1) and then click Modify Selected.
In the next dialog box, enter all the inputs and click OK. This dialog will have different required inputs for each code.
From these inputs, the X, Y and Z values will be calculated for you.
All of these static occasional loads, can be reviewed in the Model Input Listing. Select Result > Quick Reports > Input Listing. This can also be accessed from the Home Ribbon Tab or the Report Manager.
Move “Loads Summary” over to the Selected Reports section and click OK.
This report will show an Earthquake, Wind and Snow load sections. Examples are shown below.
Also!! Remember that you have to include these occasional load cases in your analysis sets in order for them to be applied. Select Analysis > Static Analysis Sets.
Select Create Default Sets.
Set up a single or multiple analysis sets but make sure the Include Occasional Loads option is checked on.
Alternatively, click New to manual create an analysis set. Then select the row and click Modify to customize each analysis set.
Make sure the desired static occasional loads are checked on to be included.
Review the loads being included in each analysis set back in the Analysis Sets dialog.