Support Types
Support Types
|
Each of the Six Degree of Freedoms (DOF) at the bottom node of the columns can be restrained or unrestrained. Furthermore, each of these DOF can be assigned torsional or axial springs whose spring constants are to be determined by the user. |
In order to create Support Types to be assigned to bottom node of a column:
-
Select “ Support Types” option in the “ Modelling ” tab.
-
The “ Support Types ” form will be loaded. “ Default ” Support Type in the list corresponds to a full restraint at each of the six DOF. In this case, all columns and walls at the S T:01 level will have fixed supports while other bottom DOF of the upper columns and walls will not be restrained at all.
-
To create a Support Condition other than “ Default ”, press “ Add New ” button on the same form. A new support category with all DOF restrained will be added to the end of the list.
-
Six degrees of freedom consists of following components:
-
X: displacement along global x axis.
-
Y: displacement along global y axis.
-
Z: displacement along global z axis.
-
X-Rotation
-
Y-Rotation
-
Z-Rotation
A checked box just near the DOF means that related DOF is restrained. If this box is unchecked, “ Spring Constant ” field will be enabled. You can either enter a Spring Constant consistent with the current unit system or just leave it zero to fully unrestraint the DOF. -
User can also select the icon button under "Fast Restraints" section to quickly define the restraint type such as "Fix"
, "Pin"
, "Roller"
for direction X and Y.
-
Close the “Support Type” window by pressing “OK” button after creating the adequate number of support types.
For the buildings with columns ending up at different basement elevations, just create a fixed support type other than “Default”. Then assign this Support Type to the related columns at the lowest level as described above.
Soil-Structure Interaction type solutions can also be achieved by the help of this option. However, spring constants which are closely related with the soil parameters must be selected carefully. A faulty value selected as the axial spring constant will affect all super-structure force and moments.
Pinned Support
There are two methods to define the column support condition to be pinned. However both result will be different, therefore user have to decide which method to apply when defining pin condition to your member.
- Set Support Types to Pin Condition and applies to column properties.
Section eccentricity to the center will be considered and calculated (distance x axial load = moment).
- Remain Support Types to be "Default " but set Hinge type to "Hinge Bottom" in Column Properties.
Column bottom will have zero moment regardless of section eccentricity.
Related Articles
How to Model a Roller Support
When modelling a truss in ProtaStructure, it must be supported by a column, wall or another beam. Hence, the supporting member must be modelled for the truss to sit on. If you want to assign a special support, such as a roller support, it must be ...Working with Walls
Defining a New Wall Before inserting a wall member its reference axes must be defined. Walls are defined by two axis intersection points (insertion points) defining the start "I" and end "J" of the member. Hence for wall, 3 axes are needed for create ...ProtaStructure Basic Training Guide
Thank you for choosing ProtaStructure. This Basic Training Guide aims to get you up and running quickly. Starting from an introduction to the interface, this guide explains how to create, analyze and design a model step-by-step. You should be able to ...How to model a Foundation at Different Level/Storey
What is a default support? Default Supports Method The support provided by default is dependent upon the storey level at which the column or wall stops. For columns and walls that stop at ST: 0 (i.e. the foundation) — Default = Fully Fixed Support ...ProtaStructure Suite 2026 New Features
As Prota, we have been developing leading structural BIM software for over 40 years. Priority on our product strategy has always been: Providing new practical modeling approaches Introducing innovative design technologies that will add value to your ...