School of Civil Engineering

Strength improvement of soft soil based on a novel evaporative dewatering method

The increase in the population and infrastructure developments within the past few decades caused an increase in the development on soft soil deposits which needs to be preconditioned or improved prior to the construction of overlying structures. In addition to the existing soft soils, newly reclaimed lands from the ocean, riverbed and lakebed are also needed to be improved. Land reclamation projects are carried out in order to expand the adjacent facilities such as ports. In an environmentally feasible way, maintenance dredged mud can be reused as the filling materials (e.g. the Port of Brisbane expansion project). This dredged mud is predominantly fine-grained with low shear strength, difficult to dewater and consolidate and undergoes large settlement which causes many problems in engineering applications. Several techniques are available to increase the strength of soft soils prior to the commencement of construction activities, however, it is important and needed to have a flexible and efficient method for dewatering of fully saturated soft porous materials. Therefore, a new method is being proposed to effectively dewater and densify soft soils by applying controlled air flow within boreholes. Airflow can create the suction within soft porous materials and force water to flow out of the pore structure towards the boreholes. This method will densify and increase material shear strengths surrounding the boreholes. The approach requires an improved understanding of the evolution of soft soils’ strength during the densification process. Therefore, a series of lab and field tests have been designed and partially carried out in this research which the results will be of great significance for soft soils dewatering not only for Australia but also internationally.

10:00am - 11:00am

Wednesday, 28 November 2018


AEB Seminar Room 502
Advanced Engineering Building (49)