Understanding the Curve library

Summary	What do you model in the Curve library?

Summary	What do you model in the Curve library?
Related Function	Base > Library > Curve Curve Library & Assembly Unit
Type	FAQ, Tip, Verification, Example

Q. What does the Curve Library model?

A. In Curve Library Mode, structures whose shape changes according to alignment changes such as slabs, median strips, and crossbeams are created.

CIM's modeling is based on the Library. This is the basic composition method of the Curve Library, which is one of the library components.

When Base > Library > Curve > Create is operated, the setting screen is entered, and the Default Constraint Path of Unit Length and Constraint Plane at both ends of the path are created.
In the default setting of the Curve Library, you can set the name of the library, the unit length of the library, and the direction.
The direction is set based on the global coordinates of the modeling window and can be set in the global +X, +Y, +Z, -X, -Y, -Z directions from the GCS origin (0,0,0).

Figure. 1 Curve Library Setting Dialog

The model space of the Curve Library is a group of modeling elements based on alignment or length.

It is a modeling space with a basic unit length to be applied to the assembly unit or Base Mode ( Layout or Line ) of a higher concept.

Figure. 2 Models created in the Curve Library

Models whose shape itself is affected by alignment changes such as slabs, median strips, crossbeams, cables and railings of cable bridges,

Section and alignment-based models are created in Curve Library Mode.

Objects created in Curve Library Mode can have constraint information through two types of Linked Entity functions.

Objects without constraint information exist only in Mode and do not appear at the time of assignment.

The types of Linked Entity are as follows.

Linked Entity type of Curve Library

Path Linked Entity: 1D object that has a constraint in one main path and is created based on section and path information.
The shape changes according to the shape of the Main Path assigned to the alignment.
Point Linked Entity: An object that has one constraint point and constraint, and is dependent on the position change of the constraint point without changing the shape, and only moves the position.
(If you use the Point Library Import function in Curve Library Mode, it becomes a Point Linked Entity.)

By importing the model from the Point Library, it is possible to configure the model in the Curve Library.

However, since the information model itself is imported and there is no link relationship, the update is not reflected when modifying the Point Library model later.

The types of Constraint Entity that can be created in Curve Library Mode are as follows.

Constraint Entity that can be created in Curve Library Mode

Constraint Plane: Used to create the Main Path, and defines the location and alignment rules of the Start/End Points of each Main Path.
Main Path: It is used to create Path Linked Entity, and Constraint Point for Point Linked Entity can be created on the Main Path.
The shape of the entire Curve Library is determined according to the shape of the Main Path at the time of alignment assignment.
It has offset information (Y, Z).
Constraint Point: It is used as a reference point to define an object to be placed at a point in the alignment as a Point Linked Entity.
Constraint Array Point: It is used as an Array reference point of objects to be arranged according to the Arrangement rule on the alignment.

Detailed explanations for understanding each Constraint Entity can be found in the respective technical documentation.
　Understanding the Constraint Entity(Plane)
　Understanding the Constraint Entity(Path)
　Understanding the Constraint Entity(Point)

The example below is an example of modeling a PSC BOX with a unit length of 50m with a Curve Library and assigning it to a layout.

Figure. 3 Curve Library (10m unit length PSC BOX upper model)

Figure. 4 Base Mode (PSC BOX model assigned to curved layout)

Figure 3. is an example of modeling PSC BOX in Curve Library Mode with unit length of 50m. (Set the constraint plane to accommodate the length change at the center of the span)

Figure 4. shows the Curve Library model of Figure 3. assigned to curve layouts of different lengths in Base Mode.

The figure below is an example of changing the configuration of the branch of the PSC Box model only by changing the location of the constraint plane.

Figure. 5 Modifying the model using Constraint Entity