Create concrete cores

Tekla Structural Designer
Tekla Structural Designer

Create concrete cores

Tekla Structural Designer allows you to combine concrete wall panels, columns, and beams to form cores.

Overview of concrete cores

Concrete wall panels, columns, and beams can be combined to form cores for which overall analysis results are automatically calculated and available for review and output.

Such cores might then be used in a number of ways, for example:

  • The engineer may wish to see/ output core forces to; better understand the distribution of lateral forces within the structure; for additional checks they wish to undertake; for overall core foundation forces or exclusive core reactions for cores on foundation mats.
  • Cores provide a way of checking lateral forces per object type or SFRS type. This might be used when assessing buildings for some codes which require frames in dual systems to resist a minimum amount of seismic load.
  • Adding all elements of the lateral system to a single core will give overall building vertical and lateral load, overturning moments or accumulated seismic torsion, in any direction.
Any number of walls (meshed and mid-pier), columns, and beams can be added to a core.
  • Constituent objects of a core do not need to be physically attached.
  • Once defined the core is listed in the structure tree and can be graphically selected as a single entity. When selected, its properties are displayed in the Property Window and Delete, Move, Copy and Mirror operations can be applied to it.

The directions of each core can be defined as any of; Dir 1/2 - Main Building Directions; Principal 1/2 - Major and minor local axis; Angle - (w.r.t.) Global Coordinate System.

The following core properties are automatically calculated/ displayed; Core section for each level; Core centroid and its coordinates above and below each level; a Core line with Local coordinate system (LCS) assigned and displayed at the centroid location; a Core support (for reporting purposes not analysis).

After analysis the following core results are available:

  • Core Line Forces - 2D Integrated Results termed “Core Line” results for cores giving the following overall core forces; Axial Force, Major and Minor axis Moment and Shear, Torsion.
    • In the Results View via 2D Integrated Results > Core Lines, force diagrams of these results are displayed along the core line w.r.t. its LCS, with numerical values displayed at the top and bottom of each core stack and in the Tooltip when the result diagram is cursored over.
    • Results are available for all of; All Static Analyses including chase-down; RSA Seismic both for individual modes and Modal combination; Imposed/Live load reductions.
    • Tabular Results - Core results are also available in Tabular form via Analyze > Tabular Data and the associated Report option Analysis > “Core Line Forces”.
      Note: Settings controls in the Member Forces and Wall Line Forces Report items allow you to optionally exclude columns/walls assigned to cores.
  • Core Reactions - overall Reaction results are calculated for the core and can be viewed in the Results view via Reactions > Cores and output.

Create concrete core (assisted mode)

Cores are either created in Assisted or Unassisted mode. In assisted mode (which is the default), all potential members of a core are automatically highlighted when the cursor is moved over any of the constituent members, giving a preview of the core that can be created - a single click then adds all the highlighted walls to a new core.
  1. On the Model tab, click Cores.

Assisted Mode

  1. In the Properties window, select Assisted.
  2. Select an appropriate wall panel or column and all highlighted members are added to the core.

    The mode switches to Modify to enable you to edit the core if required.

  3. If no modifications are required, press Esc to finish.
    Note: Assisted Mode detects overlapping concrete walls, columns and coupling beams* that may potentially form a core.

    *Beams for which the Construction property is set = “Coupling Beam”. Note that no additional design checks are performed for this construction type so currently it serves only to mark beams; for consideration by the assisted mode core function; for which additional design checks beyond those currently made in the program may be required.

Create concrete core (unassisted mode)

  1. On the Model tab, click Cores.
  2. In the Properties window, unselect Assisted.
  3. Select either a wall panel or column as the first member of the core.
  4. Select the next wall panel, column, or beam to be part of the core.
    Note: You can drag the mouse pointer to select multiple members.
  5. Continue selecting until all the members of the core have been chosen, and then press Esc to finish.

    Tekla Structural Designer combines the selected members into a single core.

Set the core axis direction

Analysis results are displayed with respect to the axis diection of each core. This can be aligned to the main building directions, the major and minor local axis, or to a specified angle.

  1. Select the core.
  2. In the Properties window, choose the rotation angle as required.

Modify concrete core

  1. On the Model tab, click Cores.
  2. In the Properties window,
    1. Set Mode to Modify
    2. Select the Active Core as required.
    3. Set Area Selection Mode to Set On to add members to the core, or Set Off to remove members from the core.
  3. Select a member to add or remove from the core.
  4. Continue selecting or press Esc to finish.

    Tekla Structural Designer combines the selected members into a single core.

Dissociate concrete core

Existing cores can be disconnected if required.

  1. Hover the mouse pointer over the core.
  2. If a different entity is highlighted, press the <down arrow> cursor key until the required core reference is shown in the Select Entity tooltip.
  3. Right click and select Dissociate Core.
Was this helpful?