Canberra Event: Ground Improvement for International Container Terminal Project at Webb Dock Melbourne
Dr. Kejing Chen
The presentation will cover one of the projects he involved for the International Container Terminal Project at Webb Dock Melbourne. The project is located on a reclaimed land at Port Melbourne underlain by high compressible marine clays referred to locally as Coode Island Silt (CIS). The proposed development imposes additional ground surcharge of 55 kPa (stack of 5 containers high) and repeated loads of 360 kN/wheel (Automated Stacking Cranes). It was estimated that without ground improvement the development could potentially be subjected to settlement of up to 500 mm over the 27 year design life. Ground improvement was necessary in order to satisfy the operational and maintenance requirements for the development. This presentation will focus on the pre-loading – one of the ground improvement methods adopted for the project. Other methods, such as CMCs and impact rolling will be briefly discussed.
The pre-loading study comprises a review of the site reclamation history, followed by the consolidation back analysis using PLAXIS 2D to study the historical settlements associated with the previous reclamation and land use and their effect on the future development with and without the adoption of preloading. A pre-loading program was then decided that involved the application of up to 5.5 m high compacted earth fill (surcharge equivalent to twice of the maximum design load of the 5 stacked containers) for a period of 2 to 3 months, targeting to remove over 40% of the potential total settlement under the container stacking loads. The monitoring of pre-loading was undertaken using settlement plates, inclinometers and vibrating wire piezometers, that were employed to verify the target consolidation settlements. The study concluded that the design intention had been achieved by the completed preloading ground improvement program. Comparison of the measured settlements in the first 5 year option with the predicted shows good agreement.
About the speaker
Dr. Kejing Chen Associate Director, AECOM
Dr. Kejing Chen is an Associate Director at AECOM and Fellow of Engineering Australia. Kejing has over 30 years of experience in geotechnical engineering. His expertise includes soft soils, slopes, ground retention and piling. In the last ten years, Kejing has been the design lead for many major projects, including Regional Rail Link- City to Maribyrnong River, Victorian International Container Terminal Development at Webb Dock, Melbourne Metro Tunnel Project (RIA) and Level Crossing Removal Projects.
Engineers Australia members participating in AGS technical sessions can record attendance on their personal CPD logs. Members should refer to Engineers Australia CPD policy for details on CPD types, requirements and auditing guidelines.