Form: Shell Load Assignment - Temperature
Temperature loads for shell objects may be based on a user-specified uniform temperature change, or they may be based on previously specified joint object temperature changes at the joint objects at the corners of the shell object, or they may be based on a combination of both.
Assign temperature loads to shell objects as follows:
Select the shell object(s) to which temperature load is to be assigned.
Click the Assign menu > Shell Loads > Temperature command to access the Shell Load Assignment - Temperature form.
Use the following drop-down list, edit box, check box and options to specify the appropriate parameters for the load:
Load Pattern Name drop-down list. Select the name of a defined load pattern to which the specified shell object temperature loading is to be assigned. Note that the Define menu > Load Pattern command is used to define load patterns.
Uniform Temperature Change edit box. Specify the uniform temperature change, if any, for the object. If the temperature load for the shell object is being based on the joint temperatures at the end of the object only, enter 0 for the uniform temperature change. A positive temperature change corresponds to an increase in the temperature of an object.
Include Effect of Joint Temperatures check box. When this check box is checked, ETABS considers the temperature change in the shell object based on previously specified joint object temperature changes at the joint objects at the corners of the shell object. ETABS assumes that the temperature change varies linearly over the surface of the shell object based on the specified changes at the corner points. Note that the effect of the corner joint temperatures is not additive to itself; the corner joint temperature is considered (checked) or it is not (unchecked). Thus, the Uniform Temperature Change value has no effect on the option of including the effect of the joint temperatures, and the joint temperatures have no effect on the uniform temperature change specified in the Uniform Temperature Change edit box. A uniform temperature change and a temperature change based on specified corner joint temperatures can both be specified if required. However, probably more commonly, only one type of temperature change is specified.
Object Temperature Options
IMPORTANT NOTE: These options apply to the uniform temperature change as specified in the Uniform Temperature Change edit box only. They have no effect on the end point temperature option. The end point temperature is considered (check box is checked) or it is not (check box is unchecked).
Add to Existing Temperature: Adds the specified uniform temperature change to the shell object. If one or more uniform temperature change assignments have already been made, this option increases the total uniform temperature change on the shell object, assuming a positive uniform temperature change is being specified.
Replace Existing Temperature: Replaces the currently specified uniform temperature change, if any, with the new uniform temperature change assignment. If no assignment exists, the new assignment is still made. This is the default option. Note that only the temperature changes in the load pattern that is specified on the form are replaced.
Delete Existing Temperature: Deletes any and all uniform temperature change assignments made to the selected shell object(s). When this option is selected, any value input in the Uniform Temperature Change edit box is ignored when the Apply button is clicked. Note that only the temperature changes in the load pattern that is specified on the form are deleted.
Note that the default option is Replace and that the program defaults to this every time the form is opened.
Click the Apply button to complete the assignment.
When the Apply button is used, the Shell Load Assignment - Temperature form will remain open until it is closed by clicking the Close button. This allows selection of another frame object(s), to which another assignments can be made.<="">
If only one assignment is being made to only one set of selected objects, the OK button can be used to both apply the assignment and close the form.
See also: