## Function

- Define tendon profiles that will be assigned to longitudinal members.

## Call

From the main menu, select **[Structure] tab > [PSC Bridge] group > [PSC Box Bridge] > [Grillage Model]**

## Input

Grillage Model Tendon dialog box

### Tendon Profile

#### Tendon Property

Select the tendon property. Click to the right to add new, modify or delete previously defined tendon properties.

#### Input Type

The dimension of Tendon Profile is specified.

**2D** : Tendon Profile is defined in 2-dimensional coordinates.

**3D** : Tendon Profile is defined in 3-dimensional coordinates.

#### Curve Type

Specify the type of curvature for tendon placement.

**Spline** : Calculate the minimum polynomial curvature connecting the points defining the tendon profile and auto-place the tendons.

**Round** : Place the tendons following the circle, which forms tangents to the straight lines connecting the points defining the tendon profile.

#### Typical Tendon

This is a function for defining a lumped representative tendon. If this option is checked on and the number of tendons is inputted, the generated tendon profile is multiplied by the inputted number of tendons when analysis is performed. For simple analysis, such as the schematic design of a bridge, inputting 3 dimensional tendon profiles is time consuming. Therefore, using the function of lumped representative tendon, which defines only one tendon profile for analysis, the time required for generating the model and performing analysis can be reduced.

After analysis is performed, the results for only one tendon are displayed.

#### No. of Tendon

Number of lumped representative tendons.

#### Type of Input

**Distance** : The actual vertical distance of the bridge.

**10th Point** : Divide the span into 10 even parts and use distance rates to make inputs.

#### Ref. of z-axis

The origin of the z coordinate.

**Top** : Distance from the top.

**Bottom** : Distance from the bottom.

#### Point of Sym.

Copy symmetrically the Tendon Profile entered in the table.

**First** : The starting point of the current Tendon is assumed to be the axis of symmetry.

**Last** : The end point of the current Tendon is assumed to be the axis of symmetry.

**Make Sysmetric Tendon** : Tendon Profile is created on the basis of the selected symmetry point (First or Last).

#### X-Axis Rot. Angle

The tendon profile placed in the table is rotated about TCS (Tendon Coordinate System) x-axis by the Angle. This is usefully implemented when placing a tendon on an inclined (non-vertical) web.

X-Axis Rot. Angle must be entered between -85 and +85 degrees.

#### X-Axis Direction

Direction: Define the x-axis of TCS for tendon placement.

**L->R** : The x-axis in TCS is defined in the direction from the left to right of the element.

**R->L** : The x-axis in TCS is defined in the direction from the right to left of the element.

#### Offset

Move the tendon by the offset distance from the origin.

#### Auto Generate

Copy the inputted tendon profiles to the other longitudinal girders. The x and z coordinates remain identical and the y- coordinates are the same as the centroid of each longitudinal girder.

### Pretension Load

Specify the magnitude of the prestress loads to be applied to each tendon profile in force/stress unit.