Noarlunga, South Australia

BEENGS geotechnical team provided on the Seaford Rail Line Extension project that provided a 5.7-kilometre extension of the dual-track rail line from Noarlunga Ctr Railway Station to the Seaford District Ctr, including stations, bus interchange and parking facilities. The total value of this project was $291 MIL. This was in addition to a 1.2-kilometre elevated rail bridge than spans over the Onkaparinga Valley. The project was segmented into five major design stages. These stages include a preliminary geotechnical investigation & reporting, shallow footing design, retaining wall design and geotechnical stable slope.

The geotechnical investigation identified the soil condition and properties of the vicinity, where a formal geotechnical report was submitted for design recommendations. Thus, provided the fundamental basis of the entire design project. Due to the soft cohesive soil conditions, accelerated soil consolidations were considered – Vacuum Preloading and Prefabricated Vertical Draining Systems were considered and implemented into the construction process. A recommended concrete footing size of 6x4x2 m and a cantilevered concrete retaining wall of 6x4x0.6 m was designed for construction. A qualitative analysis via GeoStudio – Slope/W software allowed our team to design a geotechnically stable slope based on the slope steepness angle.