Blanchetown Bridge Geotechnical Investigation

A geotechnical investigation for a proposed replacement bridge at Blanchetown, South Australia was carried out. The investigation comprised drilling, coring, field and laboratory testing, analysis, pile testing and reporting. The background to the geotechnical investigation, the investigation methodology and the investigation results are briefly outlined, and a model of the geotechnical profile along the proposed bridge alignment is presented. The main geotechnical issues for the design and construction of the proposed bridge are then discussed. These comprise design and constructability of the bridge pier and abutment footings; slope stability and excavatability of the western bridge approach cutting; use of the excavated material as fill; settlement performance of the eastern bridge approach embankment; and design or construction techniques to minimise the effects of embankment settlement.