Engineering and Information Sciences

People

Martin Liu



Current Positions:

Senior Lecturer, Faculty of Engineering, UOW

Biography:

University of Wollongong Senior Lecturer
(February 2009) Faculty of Engineering

University of New South Wales Researcher Associate
(January 2006 to February 2009) School of Civil Engineering

Sydney University Researcher Associate
(July 1995 to December 2005) Department of Civil Engineering

Kiso-Jiban Consultants Co. Ltd., Japan Senior Consultant
(April 1992 - December 1994) Numerical Analysis Section

Nagoya Institute of Technology, Japan Visiting Professor
(June 1991 - March 1992) Department of Civil Engineering

Glasgow University, UK Doctor of Philosophy in soil mechanics
(Oct 1987 - March 1991)

University of Cambridge (Trinity) Master of Philosophy in soil mechanics
(Oct 1986 - Aug 1987)

East China Technical University Bachelor of Engineering in
of Water Resources, China Hydraulic Structure Engineering
(Sept 1980 - July 1984)

Research Interests:

(1) Constitutive modelling of the behaviour of geomaterials including rock joints based on available experimental data. A number of research topics can be included in this category, such as a study on one type of geo-materials (i.e., clay, sand, calcareous soil, gravel, rock, or rock mass), a particular structure that found in nature or artificially formed for special engineering purposes including geosynthetics soils. Also included in this category of research is the behaviour of structured soils under special circumstances such as cyclic loading, creep effect, strain rate effect, temperature effect, degrees of saturation, and fissures.
(2) A study of the development and formulation anisotropy in engineering geomaterials and its influence on their mechanical behaviour.
(3) Numerical analysis of soil and structure interaction, such as developing finite element analysis codes for new constitutive models and new structure elements, and solving boundary value problems encountered in geotechnical engineering practice.

Professional Activities:

The three most significant accomplishments:
(A) A compression model for structured clays (2000). The model is increasingly used as a standard tool for representing natural clays, a significant step forward from the conventional linear e - lnp' representation for laboratory reconstituted soils.
(B) A theoretical framework, the Structural Cam Clay (2002). The SCC has been used as a key platform to understand and model mechanical properties of natural soils and to solve engineering problems by researchers in several countries.
(C) A complicated philosophical model, the Sydney Soil Model (2010).
Based on the collaborated work in the past ten years, Liu and Carter and Airey recently proposed the Sydney Soil (SS) Model (2010). The SS model makes major breakthrough of the theoretical framework of the Cam Clay. The formulation of Cam Clay in 1950s is a revolution in modern soil mechanics, which unifies soil mechanics into a cohesive science, the Critical State Soil Mechanics. However, the Cam Clay is based on and suitable for laboratory reconstituted clays. It has two basic behavior patterns. Almost all existing models are confined to these two types of behavior patterns. The SS Model is formulated based on two fundamental assumptions (i.e., the existence of the intrinsic final failure state and the plastic-volumetric-deformation-dependent hardening). The SS Model successfully unifies the behaviour of two types of soils, clays and sands, into a single theoretical framework with the introduction of the influence of soil structures (both naturally and artificially formed) into the classic soil plasticity. Different patterns of soil behaviour other than the two predicted by Cam Clay are interpreted and predicted satisfactorily.

Future Research Topics:

(1) The most challenging and exciting topic: understanding the mechanisms of anisotropy in general and formulating a theoretical framework for modelling the variation of the mechanical properties of engineering materials associated with anisotropy.
(2) Constitutive modelling of the behaviour of rail materials, particularly under a large number of cycles, formulating a complete hydraulic-mechanical models for ballast.