Sleeve shift on collision with lattice girders for iWall

When generating or modifying a wall generated using the Design (iWall)) tool, an automatic offset of the Cast-in nuts can be selected if they collide with the Lattice Girders. As a result, Allplan 2023 no longer features complex checks and reworking that had previously been necessary, for example, to prevent the cast-in nuts in the second leaf from being flattened by the Lattice Girders when the leaf produced first of all is turned in.

To define whether or not a check and therefore a subsequent offset of the cast-in nuts should occur, the Cast-in Nut Offset was expanded under Basic Reinforcement,… on the Cast-in Nuts tab in the Other Cast-in Nut Parameters subdialog.

The Consider Collisions with Lattice Girders = Yes/No parameter (check box) had been added in the Cast-in Nuts Offset group. This check box is only visible for a span direction (setting on the Basic reinforcement,… tab in the Basic reinforcement general group) of 0 ° (= Lattice Girders Perpendicular in Element). No setting can be made for any deviating values for the span direction. The offset of the Cast-in Nuts may need to take place manually, where required.

If the check box remains disabled, the algorithm will remain complete unchanged. If the checkbox is active, an Offset to lattice girders parameter appears. Here enter the required offset of the mounting part for the sleeves to set the lattice girder axis. The offset is always based on the enveloping min-max box of the fixture.

Note: In the following investigation, only those Lattice Girders that can be generated using the automatic features in iWall are investigated. These are the normal Lattice Girders and the intermediary carriers for the Concrete wall, Double·wall and Thermal·wall Design Modes. In the case of the Thermal wall, the auxiliary lattice girders are also considered. Please note the aforementioned Lattice Girders, intermediate carriers or auxiliary lattice girders in the event of a manual offset, copy, etc., or the manually generated secondary lattice girders, which have been integrated into the Element Plan or the panel editing using the Secondary Girders or Shear Girders tools in Secondary Reinforcement, cannot be controlled.

If the Consider Collision with Lattice Girders option is active and Lattice Girders have been added in the corresponding element in the first place, a Collision Check and, where required, an offset of the Cast-in Nuts will be undertaken. The Cast-in Nuts will initially be positioned according to the existing rules. Checks are then made to see if the C-i nut is located within the sphere of influence of a Lattice Girder.

The sphere of influence of the Lattice Girder is defined by the value stipulated under Offset to Lattice Girder Axis. This is applied to the left and right next to the Lattice Girder axis.

If the C-i nut is not located within this sphere of influence, a valid position is therefore found for the C-i nut. If, however, a C-i nut is located within the sphere of influence specifically on or to the left or right next to the Lattice Girder axis, this must be offset further.

Note: It is only the Lattice Girder axis and the position of the fixture that will generally be investigated for the Cast-in Nuts. There is no real Collision Check undertaken between the Lattice Girders and the fixtures. In the case of flat Cast-in Nuts that do not collide with the Lattice Girder at all, the Consider Collision with Lattice Girders option must therefore be switched off where required.

The direction of the offset is in accordance with the configured variant for the Offset of Cast-in Nuts parameter.

• If the configured variant Only horizontal is selected, the C-i nut is therefore offset further in the direction (left or right) next to the Lattice Girder into a position where it is next to the Lattice Girder.
  
  If the C-i nut is located precisely on the Lattice Girder axis, it will be offset outwards (to the left or right, i.e. away from the center of gravity).
  
  Note: When selecting the Center of gravity option for C-i nut arrangement, the C-i nut will always be displaced to the right.
  
  The C-i nut is therefore offset until the min-max box of the C-i nut is completely outside of the defined range.
• If any is the chosen variant, the C-i nut will initially be displaced horizontal, vertical or in any direction (depending on the shortest distance). If it is positioned within the sphere of influence of a Lattice Girder, it will be offset further until it is outside of the sphere of influence.
  
  However it will only be offset horizontally, analogous to the Only horizontal variant. As a result, the same rules regarding the direction of the offset and the min-max box of the C-i nut as those applicable to the Only horizontal variant will apply.

Finally, checks are made once again to see if the Minimum spacing from openings and Minimum spacing from element edges offsets in the Edge offsets group of the Other Cast-In Nut Parameters subdialog, which is found on the Cast-In Nuts tab under Basic reinforcement,... have been observed.

If this condition is met, a valid position is therefore found for the C-i nut. If, on the other hand, the C-i nut slips too close to an opening, an element edge or one of the following, automatically generated Lattice Girders owing to the additional offset, it will be left in the original position before the additional offset, and the message Minimum spacing of C-i nut from the Lattice Girder cannot be observed owing to a clash in spacing’ will appear. Please change the parameters output.