Bridges

The scale of local infrastructure projects is rapidly growing, where cut and cover tunnels are now larger than ever. Traditionally cut and cover structures have been classified as 'simple structures' or 'big culverts,' however, in recent projects we are seeing cut and cover spans exceeding 15 metres, challenging this classification.

This paper explores the design challenges faced on the North East Link (NEL) Project at the Bulleen Cut & Cover structure. This structure is a crucial element in Victoria’s largest road project in history, playing an essential role in connecting the Eastern Freeway and the M80 Ring Road.

The Bulleen Cut & Cover structure is a 625-meter long, top-down, single-pass wall system, with diaphragm walls and barrettes extending to depths in excess of 25 metres. With widths ranging from 47 to 57 metres, and design floodwater design levels 18 metres above the roof level, this structure has pushed the boundaries of cut-and-cover design, presenting complex design challenges.