Shiao Huey Chow
BEng (Hons) MEng
Postgraduate Research Student
Centre for Geotechnical Research
School of Civil Engineering, Room 101
Phone: +61 2 9351 5155
Fax: +61 2 9351 3343
Research project - Rapid Penetration of Objects into Clay
Supervisor: A/Prof David Airey
Shear strength of soil is a critical design parameter in geotechnical engineering. Obtaining soil strength parameters can be costly for sites with poor accessibility such as seabeds. These seabed sediments are often very soft and obtaining high quality soil samples and testing their mechanical behaviour in the laboratory pose considerable challenges. One solution is to use free falling penetrometers to determine the strength in-situ. The penetrometers (retrievable or expendable) can be deployed from small vessels and be allowed to free-fall into the seabed. Free fall penetrometer tests are relatively rapid and enable wider test area coverage at lower cost than conventional offshore in-situ tests. As a result of these advantages, numerous free falling penetrometer systems have been developed. Despite successful field trials for the many penetrometer systems, their applications are still not wide spread mainly due to uncertainties in the data interpretation. Accurate data interpretation is hard to achieve due to poorly understood viscous rate effects observed in the test, which results in overly high dynamic soil resistances being measured under the high velocity penetration. The challenge therefore lies in relating the dynamic soil resistance to the static soil strength.
This research therefore aims to investigate viscous rate effects associated with the rapid penetration of free falling penetrometers into clay. The viscous rate effects are investigated using extensive laboratory rate studies consist of different soil tests sheared at a wide range of strain rates. Among the rate studies conducted include laboratory model free falling penetrometer tests, Ko consolidated undrained triaxial compression tests and vane shear tests. With better understanding of viscous rate effects based on these studies, an improved interpretation of free falling penetrometers will be proposed, that enables the undrained shear strength to be reliably estimated.
- Chow, S. H. and Airey, D. W. (2011). Rate Effects in Free Falling Penetrometer Tests, Proceedings of the 5th International Symposium on Deformation Characteristics of Geomaterials, Seoul, Korea. In-print.
- Chow, S. H. and Airey, D. W. (2011). Soil Strength Estimation Using Free Falling Penetrometers, Journal and News of the Australian Geomechanics Society, Vol. 46, No. 1, pp. 105-112.
- Chow, S. H. and Airey, D. W. (2010). Laboratory Free Falling Penetrometer Test into Clay. In S. Gourvenec & D. J. White (Eds.), 2nd International Symposium on Frontiers in Offshore Geotechnics (pp. 265-270). Perth, Australia: Taylor & Francis Group, London.
- Chow, S. H., Nazhat, Y. and Airey, D. W. (2010). Applications of High Speed Photography in Dynamic Tests. In S. Springman, J. Laue, & L. Seward (Eds.), The 7th International Conference on Physical Modelling in Geotechnics (pp. 313-318). Zurich, Switzerland: Taylor & Francis Group, London.
- Chow, S. H., Norshida Ismail and A Naser Abdul Ghani (2009). Shear Strength Characteristics of Sand-Waste Material Mixture. Journal of the Institution of Engineers, Malaysia, Vol. 70, No. 1, pp. 36-43.
- Chow, S. H., Chow, S. T., A Naser Abdul Ghani and Anas Ibrahim (2008). Development of a Laboratory Model Retaining Wall Test Facility. Proceedings of the Second International Conference on Science & Technology: Application in Industry & Education, Penang, Malaysia, pp. 216-222.
- Chow, S. H., Ng, S. F. and Salwah Che Mat (2007). An Investigation on e-Learning Readiness of Engineering Students. Journal of the Institution of Engineers, Malaysia, Vol. 68, No. 4, pp. 56-64.
- Chow, S. H. and Wong, K. S. (2004). Model Pile Pull-Out Tests Using Polyethylene Sheets to Reduce Downdrag on Cast Insitu Piles, Geotechnical Testing Journal, ASTM, Vol. 27, No. 3, pp. 230-238.
Learning and Teaching
- CIVL2410 Soil Mechanics