Girder Parameters
Girder Layout: The girder layout is utilized to determine the position of the girder in both the longitudinal and transverse directions. The user is not required to input the vertical elevation of the precast girders; instead, the precast girders are vertically positioned automatically based on the alignment, deck thickness, and haunch thickness of the girder.
Tendon Layout Type[Straight/Harped]: Tendon layout type can be selected as 'harped' or 'straight.' Then, the tendons in the defined sections will be used to automatically generate a 3D representation of the tendons.
If 'straight' tendon is selected, one section is required.
If 'harped' tendon is selected, two sections—one at the start and one in the middle—and the harped region length are required to create a 3D representation of the tendons. The tendons in the two sections will be automatically connected based on tendon coordinates; the user must ensure that the number of tendons in both sections is the same. The correctness of entered inputs can be quickly verified in the 3D view.
To define tendons in the section editor, follow these steps:
If you require multiple tendon layouts for various girders or need harped tendon definitions, you can efficiently duplicate the sections as necessary. To do this, start by navigating to the "Sections" in the tree view, locate the prestressed I Girder section, and then click on the three-dot menu to duplicate it as needed.
Click on 'Section Editor' in the three-dot menu to view the section in the section editor. Next, click on 'Tendons' using the + Shapes icon to add a tendon layout.
Typically, parametric tendons are used to quickly define tendons with respect to the bottom or top reference line of the section. However, users can click on the 'Enter Parameters' button to activate the UI for drawing tendons.
Refer to the screenshots below to understand the meaning of the parameters. Typically, the bottom reference edge will be selected for straight tendons to enter the distance with respect to the bottom reference line of the section, and the top reference edge will be used for harped tendons defined at the top.
Refer to the parameter explanations below for any parameters that are not defined in the screenshot.
Prestressing Type: The prestressing type is utilized solely for certain code check procedures and does not impact any other calculations.
Strand per Tendon and Strand: The parameters "Strand per Tendon" and "Strand" will be employed to calculate the tendon's cross-sectional area.
Force in Tendon: Input "0" to utilize a force equivalent to 0.75 times Fu (ultimate tensile strength) multiplied by the tendon's cross-sectional area. For any other desired value, users should enter it accordingly.
Debonding Length: Usually, the debonding length is not entered when defining the tendon layout. Instead, it is entered after the tendon layout is exploded for a single tendon. Use the edit menu to “Explode” the tendon layout after the definition is completed. Then Edit debonding length value for each tendon. Debonding lengths will be displayed graphically, as shown in the screenshot below, to represent different lengths. This allows users to verify their entered data.
Girder Start-End Section: Enter the start and end section of the girder with tendons. When the harped tendon layout is active, tendons that are at the top should be defined in this section.
Girder Mid Section: Enter the mid-section of the girder with tendons when the harped tendon layout is active.
Hor. Dist. of Harped Tendon Region: This parameter is used to determine the horizontal distance between the start and end of the harped tendon region. A symmetrical assumption is made for both the start and end regions of the girder, so the entered value will also be applied to the both parts.
Haunch Thickness: The vertical distance between the top of the girder and the bottom of the deck. This parameter will also be utilized in load calculations.
FEA Settings
Rigid Section: Rigid beams are employed to link the nodes of girders with bearing locations/supports as seen in the screenshot below. Please refer to the following documentation to understand how to define rigid sections.
Moment Release Start[Fixed/Free]: Unless the user needs to connect two different discontinuous girders using a single bearing location, the 'Moment Release Start' should be set to 'Fixed'. Changing it to 'Free' introduces a member end release in the FEA model.
Moment Release End[Fixed/Free]: Unless the user needs to connect two different discontinuous girders using a single bearing location, the 'Moment Release Start' should be set to 'Fixed'. Changing it to 'Free' introduces a member end release in the FEA model.
Mesh Size (Longitudinal): The maximum distance between nodes in the longitudinal direction is specified using the longitudinal mesh size. In most cases, a smaller mesh size compared to the entered value might be generated due to bracing locations, deck pouring, or deconstruction definitions
# of Result Extraction St.: The result extraction station settings are solely for viewing FEA composite results in either the spreadsheet or FEA view, and do not impact standard finite element analysis results like member end forces, node displacement, and node reactions. For girder code checks, exact code check stations will be utilized for FEA composite results.
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