Controlled Modulus Columns Supporting Approach Embankment for Clarence River Bridge at Harwood, NSW
摘要
As part of the Woolgoolga to Ballina Upgrade project, CMC ground improvement was required to treat the soft soil between 22 and 34 m below surface level to support the structural zone of the new southern approach embankment of Hardwood bridge with design embankment height reaching up to 8.0 m. Wick drains were designed to meet the design requirement within the general embankment area. A combination of CMC and wick drains were designed within the transition zone between the structural zone and the general embankment to allow the settlement to transition between the more restrictive settlement criteria within 20 m behind the abutment and away from the abutment. This paper details the development of the ground improvement design from the early investigation to construction. Design was performed through finite element modelling using FE software Plaxis. Quality control measures and testing of the design have been summarised to verify that the construction has been performed to the designers intent.