UKPN Services – Thameslink Substation at Three Bridges Depot
Description: Design and construction of a steel framed substation with anodised aluminium cladding system, Kingspan roof, SFA piling, drainage and FRC floors and supporting structures. Works also included block blast walls, acoustic screening, M&E, security fencing and hard landscaping.
Challenges: Investigation of the ground conditions on site indicated the bearing capacity was not sufficient to support the HV equipment and transformers. To provide sufficient foundation for the new substation, SFA piles were placed, a capping layer was dynamically compacted, and a 450mm thick reinforced concrete ground-bearing slab was constructed. A primary factor in the design was to ensure the adjacent viaduct and operational railway was kept open and safe at all times.
Key achievements and innovations: Three Bridges Substation was planned and installed in an unprecedented nine months, and is one of the most advanced of its type on the Network Rail infrastructure. It contains eight transformer/rectifiers, two auxiliary transformers, one Distribution Network Operator (DNO) isolating transformer, eight contractors, four Programmable Logic Controllers (PLCs), four Remote Terminal Units (RTUs), two AC distribution suites, four DC distribution suites, and four Voltage Limiting Devices (VLDs).
Location: Three Bridges, Crawley, Sussex
Client: UKPN Services
Completion: March 2015