Continuity Diaphragm [CUG]
- Dogukan Kilic
- Melis Ceylan
- mert.goktas (Unlicensed)
- Cagin Yakar
Continuity Diaphragm
Purpose of the continuity diaphragm is to connect two different girder units. These units are connected with beam finite elements and they act as a continuous span instead of separate simple spans.
Connected Girders at Start (DownStation): Select the start girders (down station) to which the continuity diaphragm is connected. These girders belong to a separate unit. Continuity will be established through the continuity diaphragm object not the girders.
Connected Girders at End (UpStation): Select the end girders (upstation) to which the continuity diaphragm is connected. These girders belong to a separate unit. Continuity will be established through the continuity diaphragm object not the girders. Refer to the figure below for further clarification.
The FEA representation is as follows: it connects the start and end girders with beam elements, introduces an additional node at the midpoint of these start and end nodes, and then creates transverse beam elements.
Depth: The total depth of the section can be defined using this parameter.
Additional Overhang Length Transverse Dir. Left: The cantilever length for the diaphragm on the left side, when looking upstation along the PGL, can be specified using this parameter. This distance is measured from the web of the girder.
Additional Overhang Length Transverse Dir. Right: The cantilever length for the diaphragm on the right side, when looking upstation along the PGL, can be specified using this parameter. This distance is measured from the web of the girder.
Thickness (Downstation w.r.t. Support Line): The thickness (Downstation) of the continuity diaphragm measured from Support Line where girders are connected.
Thickness (Upstation w.r.t. Support Line): The thickness (Upstation) of the continuity diaphragm measured from Support Line where girders are connected.
Material: The material of the diaphragm can be specified using this parameter. A previously defined material from the Properties > Materials section can be assigned, or a material can be imported.
FEM
Cap Connection[Yes/No]: When selected as 'yes,' additional beam elements are created between the midpoint of the continuity diaphragm and the pier cap, and they behave as a unit. Otherwise, the bearing connection will transfer the forces.
As seen in the figure, the cap connection still exists between the girder and pier cap through the bearing
As shown in the figure below, there is an additional rigid beam between the cap and the continuity diaphragm.
Cap Connection Type[Rigid/Pin]: If the Cap connection option is set to 'yes,' we offer two types of connections: rigid and pin connections. The pin connection is suitable when the forces only transfer to the pier cap without sufficient reinforcement. This behavior(pin) is achieved by using beam end releases. If there is sufficient reinforcement connecting the pier cap to the diaphragm, the rigid connection can be selected to guarantee that the concrete block moves together during rotation.