Properties of Structure
In: Data_base tree structure->Properties
The Properties of Structure window is of the second type of the general Edit/View window. It can be run by a click on the View or Edit command in the right-hand click popup menu of the data_base tree structure. Its typical composition follows:
The properties of structure are defined in order to assign parameters related to technology or to size of the tested structure to particular elements. This means that there can be nodes lying on border of two different materials or properties. The fatigue calculation solved at results averaged at nodes then runs on both bordering materials or properties, but only the higher value of damage is assigned to node.
Be aware, that all parameters defined in this dialogue are currently used only by the LESA fatigue calculation method. They have no effect if used by any other method. Even within LESA, if the chosen influence is not confirmed within the Calculation Methods window, the effect defined here will not be applied.
Except for the ID-number and textual description of the created property, the dialogue continues by definition of roughness. The user can either set the roughness in microns or uses predefined finishing from the combobox in the right side. The user can choose three different technologies used by manufacturing of the structure, or can directly input the influence factor affecting the fatigue limit.
At last, the characteristic dimension is used for definition of size effect. The user selects the typical cross-section and assigns its corresponding dimensions in mm. The equivalent characteristic dimension is computed then. Do not be surprised that once saved, the cross-section is set to plate with corresponding thickness. The characteristic dimension stays correct.
The concept of characteristic dimensions is not a very satisfying feature. I would prefer any other solution, but we have to start with something. It corresponds to solution used within FemFat. What I do not like also, is the fact that I was forced to apply it on elements. It is logical that it should be related to nodes. But I did not want to create another entity and all those cross-dependencies. I hope the concept will be abandoned soon...
Once the selected property of structure is saved it can be applied to chosen set of elements by clicking the Apply to set button. Default setup of any imported element is that its property of structure is of ID=0. This is an automatically created default property, defined in the creation of any task (similarly to default global cartesian coordinate system). The default setup of the default property is set to roughness 1 micron (polished), no special technology applied and plate of 10 mm thickness.
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