Structural Point#

../../_images/structural_point.png Create Structural Point

Command

SOF_SE_POINT

Tooltip

Creates structural points that define FE node point in the element mesh.

Sidebar

Structural Elements

../../_images/structural_point_m.png Modify Structural Point

Command

SOF_SE_POINT_M

Tooltip

Modifies structural points that define FE node point in the element mesh.

Sidebar

Structural Elements

Structural points can be used to create rigid supports, elastic supports, elastic supports as columns, halfspace piles, and column heads/haunches. Dimensions can be set to be used during calculation of punching shear and reference points in an area.

Structural points are written into the structural database (.CDB) during export. The program SOFiMSHC creates punctiform finite elements such as nodes or springs for the structural calculation.

Loads can be assigned to structural points.

A detailed description of these properties can be found in the chapter ‘SPT – Structural point’ and the following chapters of the manual SOFiMSHC.

Note

Each structural element is assigned a local coordinate system. Exported finite elements are created with the same local coordinate systems. This also affects any locally applied loads!

If the local coordinate system of a structural element requires modification, this can be done using the Align Elements command.

Available options:#

For creation of structural points, the following options are available for use:

Select Point

Creates a structural element at the chosen position.

Point in Column

Select a point within the desired column. For round or rectangular column sections, the section dimensions are automatically transferred into the general tab of the structural point dialog box. In the case of irregularly shaped column sections, the area is determined from the border and entered as a square support of equal area at its centre of gravity. Ensure that the section’s boundary is closed and that the point is not too close to a re-entrant corner, otherwise in this case, the program will be unable to find the boundary.

Select end point(s) of structural line(s)

Allows to create structural points at selected points of structural lines. This can be useful to assign boundary conditions to columns, for example.

General Tab#

Each element is given a name and a number that is shown in the drawing. This is the internal number of the element which is used for identification.

If a column with dimensions is defined, a distinction is made between the definitions of circular or rectangular sections. This is particularly important for the calculation of punching shear checks. Structural points without any defined properties are used for the definition of vertices.

To define slabs with variable thickness, the dimensions for the corner nodes could be defined via some structural points. Please notice, in this case the slabthickness has to be set to zero.

Support Conditions Tab#

Support conditions (fixed supports) can be set here for the structural points. There is a distinction between local and global support directions. A fully rigid support condition can be activated or deactivated with the tickbox All. The mixing of global and local support conditions is only possible in a limited fashion. For example, if a global support is activated, then only local moment supports are available. The program automatically greys out any support conditions which become unavailable.

Springs Tab#

Here elastic support conditions at the structural point can be defined. Spring entries can be created or deleted using the buttons at the top of the dialog box. Individual springs are then generated when the drawing is exported. These can be specified to fail in tension (set Max Tension 0). This non-linearity (cracking) can be calculated only in the ASE module. Should a work law need to be defined for a spring, this must be defined beforehand using the work laws command.

Each spring can have a result set identifier (RSET ID). Additionaly, a designation can be defined. Both options can be used to identify the result set in the analysis workflow.

Lower/Upper Column Tab#

Elastic support conditions for structural points can also be defined here. However, the spring values are not directly entered, but instead they are defined by dimensions of the adjacent elements. The value for the elastic support is calculated upon export according to the defined parameters and written directly into the structural database (.CDB). The entries after export are no longer available for editing. The calculated values are automatically entered in the springs tab during export. When entering data into the lower part of the dialog box, it is handled as though input for the adjacent column. The end fixity (remote) defines the fixity of the adjacent column at the opposite end. The value 0 represents a pinned support and the value 100 represents a fully rigid support.

The values in the structural database (.CDB) are calculated as follows:

Rotational springs with full fixity at the opposite end:

../../_images/stuetze_dreh_100.png

Rotational springs with hinged supports at the opposite end:

../../_images/stuetze_dreh_0.png

Vertical spring:

../../_images/stuetze_senk.png

The dimensions out of this tab is not used for punching design. To define the dimensions for punching design use tab General.

Column Head Tab#

In this tab a column head thickening can be defined. Column heads are only active when the Enable Column Head tickbox is checked. This can only be done after column dimensions have been given in the General tab. There are three types of column head available for use. The available column head types are changed depending on the specified system type.

Halfspace Pile Tab#

In this tab the structural point properties for the program HASE (halfspace and other stiffness elements) are assigned. The pile cross section is taken as either the dimensions of the structural points or defined with explicit input.

Explanation of the values:

../../_images/GDB_MOD028.svg

L = Length in Direction of Gravity

MANT = Force Transfer via Skin Friction

ZMAN = Inactive Pile Length (at top of pile)

Inserting values for the limit forces can be used to define limiting (cracking) values for the pile. Note that this data can be used only in a non-linear analysis.

A detailed description of this input possibilities can be found in the chapter “PILE – Piles in the Halfspace” of the manual HASE.

Loads Tab#

In the Loads tab, loads applied directly to the structural point can be defined or modified.

A detailed description of the load possibilities can be found in the chapter “POIN – Free Point Loads” in the manual SOFiLOAD.