Siemens Greenlink Interconnector

The Greenlink Interconnector is a significant project involving high-voltage direct current (HVDC) connections between Great Island, Ireland, and Pembroke, Wales. The project includes the Control Building and Converter Transformer Area, with precast concrete crosswalls designed to provide structural integrity and stability for both sections.

Control Building

The Control Building is a single-storey structure with a precast concrete composite flat roof. The main structural elements are precast concrete twin walls, which ensure the building’s lateral stability, supporting both the floor system and other framing components. The filigree slab units, with a structural screed topping, span simply supported onto these walls, transferring vertical loads efficiently.

Converter Transformer Area

The Converter Transformer Area features twin walls that are designed as free-standing in the permanent condition. These walls are part of the overall structural design but remain unbraced. They serve to provide lateral stability to the structure while ensuring the building can handle horizontal loads.

The project considers two main conditions for horizontal load transfer:

• Wind Load
• Notional Horizontal Load

In the temporary erection condition, loads are transferred through the precast concrete composite floors, walls, and beams, with adequate propping in place until connections are completed. In the permanent condition, horizontal loads are transferred via the screeded filigree slab units, which act as a diaphragm, ensuring a stable moment transfer to the precast concrete shear walls.

This structural design ensures both vertical and horizontal load management through the strategic use of precast concrete elements, optimizing the building’s stability and safety in all conditions.