Suspension Bridge

Enter the coordinates of the nodes defining a suspension bridge.

3-Dimensional : Check to model a 3-dimensional model.

A : Origin point of the cable

A1 : Origin point of the girder

B : Top of the left tower

C : Center point of the cable

Asymmetric Bridge : Check if the bridge is asymmetric.

D : Top of the right pylon

E : End point of the cable

E1 : End point of the girder

H1 : Height of the left pylon

H2 : Height of the right pylon

Enter the distances between the hangers.

Left : Hanger spacing and loadings in the left span

Center : Hanger spacing and loadings in the center span

Right : Hanger spacing and loadings in the right span

If the structure does not include hangers in the left span, enter the distance from the starting point of the deck to the pylon. It applies the same to the right span.

The number of hangers in the center span must be an odd number because the nodal information at the most sagging point must be entered.

Material, Section : Enter the material and section properties for

Main Cable : Material properties and cross-sectional properties applied to the main cable element

Side Cable : Material properties and cross-sectional properties applied to the side cable element

Typical Hanger : Material properties and cross-sectional properties applied to the typical hanger element

End Hanger : Material properties and cross-sectional properties applied to the hanger elements (referring to the leftmost hanger and the rightmost hanger)

Deck : Material properties and cross-sectional properties applied to the deck element (same with girder element)

Pylon : Material properties and cross-sectional properties applied to the pylon element

End Hanger represents the first hanger in the left span and the last hanger in the right span.
Deck is generated as a Fish-born structure.

Width : Width of the deck

Depth : Depth of the deck (If the depth remains blank, the wizard models the deck with a single girder system. However, if the depth is specified, it models a framing system with truss elements that connects a top and bottom girders.)

Deck depth is only used for formwork. For more detailed analysis, the user needs to accurately model the deck by including the stiffness.

Unit Weight : Enter the unit weight of the deck. Since 2D suspension bridge has mono-type main cables, one row of hanger supports the unit weight assigned. On the other hand, 3D suspension bridge model has dual-type main cables, and the unit weight assigned to two rows of hanger supports. Therefore, half of the unit weight of deck is supported by each row of hangers.  

Check this button to enter a different unit weight for the left, right, and middle span.

In the Suspension Bridge Wizard, the self-weight of the main cable and hangers are accurately considered during the process of finding the optimal shape of the suspension bridge. Therefore, only the dead weight of the girder and additional dead loads should be considered as loads. Loads applied at the intersection between the main cable, hangers, and their attachments, such as additional cable loads, cannot be considered in the Suspension Bridge Wizard and should be applied using the Suspension Bridge Analysis Control after the wizard process. Additionally, in order to analyze a suspension bridge without hangers in both spans, a distributed load should be input in the Deck System > Advanced... > Distributed Load section.

G1 : Distance from the end of the deck on the left span to the left pylon.

G2 : Distance from the end of the deck on the center span to the left pylon.

G3 : Distance from the end of the deck on the center span to the right pylon.

G4 : Distance from the end of the deck on the right span to the right pylon.

Slope : Define the shape of deck simply by specifying the slopes of each side span and the arc length of the center span.

Left Slope(%) : Slope at the left end of the arc

Arc Length(m) : Arc length

Right Spole(%) : Slope at the right end of the arc

Enter the arc length, (D-B) long if only the center span is sloped. In order to specify a slope throughout the entire length of the bridge, enter a length equal to or greater than (E1-A1).

Coordinate : Directly specify the Z coordinates of the deck to define the shape as desired by the user.

1. Specify the coordinates from the left span to the center span. It is assumed that the coordinates of the right span is identical to those of the left span.
2. When "Distance from Deck to Pylon" option is used, two points with an identical X coordinate are generated on the deck. Z coordinates of these two points should be identical.
3. Deck coordinates entered by using "Coordinate" option cannot be saved as *.wzd.

X-Y Plane : Display the model on the X-Y Plane.

X-Z Plane : Display the model on the X-Z Plane.

Bitmap : It displays the model in the form of a bitmap, indicating the location and shape of the data to be entered.

Drawing : Display the overall shape of the bridge using the data entries.

: It is activated when Drawing is selected. It displays the entire shape reflecting the entered data.

Horizontal Force : Horizontal forces of the main cable, which is based on the initial equilibrium state defined by the user, is automatically calculated and displayed in real time.

: The input data is used to calculate the coordinates of each node and the stress-free configuration of elements and cables, generating data and closing the Wizard window.

: Cancel the data entries and close the Wizard window.

In the dialog box, the most recently entered data is displayed as default, and the default input for the first run is the input data for the approximate 3D shape of Yeongjong Bridge, a 3D parabolic suspension bridge.

: This function allows you to load data saved in *.wzd files in Suspension Bridge Wizard. With this function, you can modify and review previously entered data within the Wizard after restarting midas Civil.

: Save the entered data in Suspension Bridge Wizard in *.wzd file format.