Bridge transition zones experience early track geometry deviation due to sudden stiffness variation, geotechnical causes, and soil moisture fluctuation. Differential settlement between bridge and its approach is a critical issue for the railway industry and no efficient solution is yet available to maintain a gradually smoothening transmission of forces between bridge and its approach. Identification of the real mechanism behind this track degradation growth is therefore important to develop a suitable maintenance technique for any specified location.

This presentation outlines possible causes of track degradation between bridge and its approach, existing mitigation techniques and their strengths and limitations, drawbacks of conservative design frameworks, and future challenges on Australian geotechnical engineers in a green railway industry.

Speaker Biography

Biyanvilage Dareeju is currently a PhD scholar at QUT. He acquired his MSc degree in Earthquake Engineering from Sapienza University of Rome, Italy. He obtained his BSc civil engineering degree with first class from the University of Moratuwa, Sri Lanka.

Samples were obtained undisturbed from the field for CBR testing, from an active zone. They were allowed to dry for different durations and tested to produce a CBR vs MC curve. The moisture content profile of the site was investigated on several occasions over six months and compared with the CBR vs MC curve to indicate the range of CBR values that might be obtained due to temporal variation.

Speaker Biography

Daniel Mellish is a current QUT undergrad studying a Bachelor of Engineering (Civil) / Bachelor of Business (Finance). Daniel completed his research project whilst working at SKM under the supervision of Dr Burt Look.

Many mine sites are exploring the feasibility of deep open pit mining. Mt Owen (Xstrata) in the Hunter Valley is the deepest coal mine in Australia at 270 m deep with associated spoil piles in excess of 330 m. Furthermore, spoil piles of the order of 800 m have been proposed at open pit mines overseas. One aspect of deep open pit mining that is not well understood is the behaviour of mine spoil of great depth. A study on the settlement and strength of coal mine spoil was conducted at UQ using oedometers of two sizes: 76 mm diameter standard and 150 mm diameter high stress capable of applying stresses up to 10 MPa.

The purpose of this study was to investigate the compressibility of various types of mine spoil and scale effects of testing in the laboratory. The results of these tests have been incorporated into a spreadsheet-based prediction tool for modelling spoil settlement. This presentation provides a commentary on the testing methodology and implications of the results on the settlement of high coal mine spoil piles.

Speaker Biography

Adrian Kho started working at Cardno in 2009 after graduating from UQ in 2009. He has been involved in various engineering projects in Australia, Papua New Guinea and Malaysia. For the past 3 years, Adrian has been on the TranscityJV team and has been involved in the geotechnical design on the Legacy Way Tunnel.

Adrian is a part-time PhD candidate within the Geotechnical Engineering Centre at UQ researching the effects of bulking, and subsequent self-weight, saturation and degradation settlements and geotechnical stability of high coal mine spoil piles.