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[CIM/Rebar] Action Rule of Hook/Align Option in Rebar Property


I wonder how Hook and Align Option are applied in CIM.



Hook is a function that creates a hook at the end of rebar. The Align Option determines how the reinforcing bars are aligned.



This document is a technical document about the rules for the Hook and Align Option in the Rebar Property to operate between rebar in Draw Rebar Mode.
In this document, the operation and utilization method of each function of hook applied between modeling of reinforcing bars, And the rules of operation of Options that define alignment from the plane are described.



Hook is a function that creates a hook shape at the end of a reinforcing bar.
Hook Property can be divided into two functions.

Direction / Location

Different Start/End Hook function is activated when you want to set different hooks at both ends.
If you activate the function, you can enter the setting of the hook at the beginning and the end, respectively.
The Start Point / End Point tab becomes active.

The direction of the rebar property determines the direction of creation of the hook.

Figure 1. Comparison of Hook creation direction between Rotate Angle and Hook Angle

This is a defining function.
Direction consists of two options.
Plane : A hook is created on the plane where the reinforcing bar is drawn.
Custom : A hook is created with the rotation angle specified by the user in a non-planar direction .

When selecting the function of Custom, change the Rotate Angle value.
A window for input is activated.
Based on the reinforcing bar that the hook is dependent on It rotates by the input value.

Location of Rebar Property is Determines where the Offset is applied.
In other words, it is a function about where the Hook is created.

Figure 2. Comparison according to location setting

Normal : Hook is created based on the inside of the transverse reinforcing bar line.
Extended : Hook is created based on the outside of the transverse reinforcing bar line.

Difference Between Hook Length and Part Length

Figure 3. Hook Length and Part Length

Even if the same input value is set for Hook Length and Part Length, due to the difference in the operation rules of the two properties, A different shape will appear.
In the case of Hook Length, the input value is applied after the curve of Hook Bending Radius for Hook Length.
However, in the case of Part Length, the Part Length is applied from the intersection of the center lines of the reinforcing bars.
Therefore, the gap between the two functions is as wide as the Hook Bending Radius.

Angle / Radius / Length

Hook Type : Select the hook type.

In Hook Type, you do not set the hook or You can choose the Hook type.

Also, select Custom to select Hook Property. User can directly input The Angle / Radius / Length input window is activated.

Angle : Input the hook angle of the hook.

Radius : Enter the radius of curvature of the hook.

Length : Enter the length of the hook.


Figure 4. Hook Angle / Radius / Length
Figure 5. Hook Action Rule

Hook Action Rule
Hook is a function that is activated after all the preceding properties are applied. In other words, if Offset, Part Length, and Hook are all set, ① Part Length - ② Offset - ③ Hook
Hook is created at the end point of the reinforcing bar determined in the process ① and ②.

When Location is set to Normal, the location of Hook creation goes beyond the end of the straight-line part of the reinforcing bar.

It is not created, but the center of the angle angle of the hook becomes the end point of the reinforcing bar when all the preceding properties are applied.
(If Location is Extend, it is the same as the operation rule of Part Length.)

Figure 6. Hook Radius and Bending Radius

By using the feature that can set the hook radius value separately from the bending radius, the curvature and You can model reinforcing bars with different curvatures at the ends of rebars.


Align Option

The Align Option, which determines the alignment method from the plane, consists of a total of 2 types.
On/From Plane Cover Align Center
Plane Alignment

On/From Plane Cover Align Center

Figure 7. On/From Plane Cover Align Center Figure 8. Plane Alignment
Figure 9. On/From Plane Cover Align Center 동작 규칙

On/From Plane Cover Align Center is located at the bottom of Cover Thickness,
You can enable/disable the function by On/Off.
When the On/From Plane Cover Align Center function is activated, the cover value (input value) is applied based on the center line of the rebar and When disabled, the cover value is applied from the outermost shell of the rebar.

Plane Alignment

Figure 10. Plane Alignment Action Rule


The Plane Alignment function is located at the bottom of the rebar property.

This function is performed by selecting the starting point / center point / end point on the Geometric Line as the constraint point of the Rebar (Start / End) plane.

This function is used as information when reinforcing reinforcing bar groups.

That is, when the geometery of the reinforcing bars currently placed in the object is changed, based on a certain point in the geometry This function determines whether to respond to shape transformation.

As in the example of Figure 10. When allocating a 1m Curve Library that has completed reinforcement to a 2m Assembly Unit, It can be seen that different shape changes occur depending on which point on the geometry is set as the reference point.

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