Professor Steeve Chung Kim Yuen
Associate Professor Steeve Chung Kim Yuen is the Deputy Director of the BISRU Centre. He is a graduate of the University of Cape Town. He obtained his BSc in Engineering (Mechanical) in 1997 before completing a Masters degree in Engineering in the field of Structural Impact (looking at deformation and tearing of quadrangular stiffened plates subjected to uniform blast load) in 2000. He completed his PhD in the field of crashworthiness in 2006. He is an NRF rated researcher (C1) and is currently employed as an Associate Professor in the Department of Mechanical Engineering. Steeve's research interests focus mostly on the response of structures to blast loading (both in air and buried charges (towards developing blast protection structures) and impact loading (crashworthiness).
Current Research
Crashworthiness
Thin-walled structures have been widely used for their energy absorption capabilities, particularly in the petro-chemical and nuclear industries as well as in crashworthiness design of vehicles (cars, buses, trains, and aeroplane) where the life of passengers is at risk in the event of a collision.
An understanding of energy absorption of structures and materials is important in, for example, calculating the damage to structures caused by accidental collision, assessing the residual strength of structures after initial damage, and designing containers to protect its contents in the event of impact. There has been a great amount of research carried out in the area over the last few decades; nevertheless the topics are gaining more eminence in the research community with the demand for increased safety.
Thin-walled structures are efficient energy absorbers provided they failed in the "right" mode of failure. Progressive buckling mode, in this case, is a more efficient mode of failure compared to the Euler mode. Nevertheless, thin-walled structures failing in the progressive buckling mode do not necessarily mean lives saved because of its high first peak load. A mean to decrease the first peak load is the introduction of geometric imperfection which can be of several natures, dent, holes, blast and any of the above in any combinations.
The objectives of the research are primarily to assess how to improve the crashworthiness of tubular structures by reducing its first peak load when dynamically compressed in the axial direction and absorbing the maximum energy. The investigations are conducted both experimentally and numerically.
Blast loading of Structures
Air blast
Extensive experimental studies have been carried out to understand the large permanent ductile deformation and rupture of plates, beams and shells. The response of thin plates, considered as one of the basic elements of structures, clamped at the outer edges or built-in at the boundary subjected to either uniform or localised blast loading conditions have been studied for a number of years.
The objectives of this research is to gain understanding and insights into the response of structures to blast load and develop ways to either mitigate or absorb the energy from a blast to protect a targeted structure.
Buried Charges
There are more than 70 states that are believed to be mine-affected. The use of landmines and Improvised Explosive Device (IED) highlights the need for better mine resistant vehicles, especially for peace-keeping forces and the demining effort. With landmine being a major threat worldwide, it has become important to investigate structural response to buried charges to efficiently develop protections systems against landmine threats.
Focus on the effects of buried charges on structures has increased. The effects of buried explosives on a structure and compared to air blast response, adds more complication to an existing complex mechanism. Research on buried charges on small scale testing has numerous advantages over full-scale tests. The test process can be better controlled in regards to accurate measurement of explosive size, accurate positioning of the explosive, easier to shape the explosive in different configurations (spherical, disc shaped of various diameter to height ratios), stand–off distance from soil level to target structure; and calibrated and controlled measurement of the impulse.
The objectives of the research are primarily to investigate on the various mechanisms and parameters that are responsible for delivering impulse to a structure subjected to buried charges.
Recent Publications
Book Chapters
- CHUNG KIM YUEN, S. and NURICK, G.N., Chapter: The use of tubular structures as cores for sandwich panels subjected to dynamic and blast loading, Blast Mitigation: Experimental and Numerical Studies, Editors: A.SHUKLA, Y. RAJAPAKSE, and M.E. HYNES, Publisher: Springer, pp 229-248, 2014.
- CHUNG KIM YUEN, S & NURICK, GN, "The Response of "Large" Square Tubes (width/thickness ratio>45) to Opposite Lateral Blast Loads Followed by Dynamic Axial Load", IUTAM Symposium on Theoretical, Computational and Modelling Aspects of Inelastic Media, Vol 11, pp. 309-317, 2008.
Journal Papers
- WANG, C., XU, W.L. and CHUNG KIM YUEN, S., Penetration of shaped charge into layered and spaced concrete targets, International Journal of Impact Engineering, Vol 112, pp 193-206, https://doi.org/10.1016/j.ijimpeng.2017.10.013, 2018.
- CHUNG KIM YUEN, S. and WARNCKE, The response of quadrangular plates to blast load resulting from the detonation of encased buried charges, International Journal of Protective Structures: Special Issue on “Research Development on Protective Structures ", Vol.8(3), pp 433-453, https://doi.org/10.1177/2041419617721547, 2017.
- AMINI, K., ALTENHOF, W., CHUNG KIM YUEN, S., OPPERMAN, C.J. and NURICK, G.N., Experimental and numerical investigation on the deformation and energy dissipation of AA6061-T6 circular extrusion subjected to blast loading, International Journal of Impact Engineering: Special Issue in honor of Seventy Fifth Birthday of Professor N. K. Gupta, Vol. 110, pp 228-241, https://doi.org/10.1016/j.ijimpeng.2017.02.003, 2017.
- CHUNG KIM YUEN, S., CUNLIFFE, G. and du PLESSIS, M.C., Blast response of cladding sandwich panels with tubular cores, International Journal of Impact Engineering: Special Issue in honor of Seventy Fifth Birthday of Professor N. K. Gupta, Vol.110, pp 266-278, https://doi.org/10.1016/j.ijimpeng.2017.04.016, 2017.
- CHUNG KIM YUEN, S., NURICK, G.N., LANGDON, G.S. and IYER, Y., Deformation of thin plates subjected to impulsive load:Part III, International Journal of Impact Engineering, Vol 107, pp 108-117, http://dx.doi.org/10.1016/j.ijimpeng.2016.06.010, 2017.
- RANWAHA, N. and CHUNG KIM YUEN, S., The effects of blast-induced fragments on cellular materials, International Journal of Impact Engineering, Vol 92 Special issue on Impact Loading on Lightweight Structures,pp 50-65, https://doi.org/10.1016/j.ijimpeng.2015.12.003 , 2016
- NIOLLET, J.E., CHUNG KIM YUEN, S., NURICK, G.N. and GIRAULT, G., A study to assess the use of cylindrical bars as blast barriers, International Journal of Protective Structures: Special Issue on “Protection of Structures against Hazards", Vol 6 (2), pp263-286, https://doi.org/10.1260/2041-4196.6.2.263 2015.
- GERETTO, C., CHUNG KIM YUEN S. and NURICK, G.N., An experimental study of the effects of degrees of confinement on the response of square mild steel plates subjected to blast loading, International Journal of Impact Engineering, Vol 79 Special issue for IUTAM 2013, pp 32-44, https://doi.org/10.1016/j.ijimpeng.2014.08.002 , 2015
- LANGDON, GS, OZINSKY, A and CHUNG KIM YUEN, S., The response of partially confined right circular stainless steel cylinders to internal air-blast loading, International Journal of Impact Engineering, Vol 73, pp 1-14, https://doi.org/10.1016/j.ijimpeng.2014.05.002 , 2014.
- ALIA, RA, CANTWELL WJ, LANGDON,GS CHUNG KIM YUEN S and NURICK, GN, The energy-absorbing characteristics of composite tube-reinforced foam structures, Composites: Part B, 61, pp 127–135, http://dx.doi.org/10.1016/j.compositesb.2014.01.018, 2014.
Published Conferences Proceedings
- CHUNG KIM YUEN, S & NURICK, GN, "Modelling of axial loading of square tubes with blast-induced imperfections" – 9th International Symposium on Plasticity and Impact Mechanics (IMPLAST 2007), Bochum, Germany , pp 553-560., 2007
- KARAGIOZOVA, D, NURICK, GN, LANGDON, GS, CHUNG KIM YUEN,S , CHI, Y & BARTLE, S, "Response of flexible sandwich panels to blast loading", 16th International Conference on Composite Materials, Japan, July 2007
- NURICK, G. N., CHUNG KIM YUEN, S., JACOB, N., VERSTER, W., BWALYA, D., & VARA, A., "Response of Quadrangular Mild Steel Plates to Large Explosive Load" [Keynote address]– 2nd International Conference on Defence and Analysis of Protective Structures, (DAPS 2006), Singapore, pp 30-44, 2006
- CHUNG KIM YUEN, S., & NURICK, G. N.,Modelling the deformation and tearing of "thin and thick plates subjected to localised blast loads - 8th International Symposium on Plasticity and Impact Mechanics, (IMPLAST 2003) - New Delhi - India, pp 729-739, 2003.
- JACOB, N., CHUNG KIM YUEN, S., NURICK, G. N., DESAI, S. & TAIT, D., Quadrangular plates subjected to localised blast loads - An insight into scaling - 8th International Symposium on Plasticity and Impact Mechanics, (IMPLAST 2003) - New Delhi - India, pp 769-776, 2003.
- NURICK, G.N., BALDEN, V.H., CHUNG KIM YUEN, S., WILLIAMS, J., STRETCH, R.A., "Measuring the position of impact of a ball striking a cricket bat - Results of three elite cricketers." Science and Medicine in Cricket - A collection of papers from the Second World Congress of Science and Medicine in Cricket, (Eds. Stretch RA, Noakes T, Vaughan CL.), ComPress, Cape Town (ISBN 1-919833-62-5), pp121-140, 2003.
- LANGDON, G. S., CHUNG KIM YUEN, S., & NURICK, G. N., The response of stiffened plates subjected to localised blast loading - 6th International Conference on Structures under Shock and Impact, (SUSI2002), Montreal - Canada, 2002.
- CHUNG KIM YUEN, S., & NURICK, G. N.,Deformation and tearing of uniformly blast-loaded quadrangular stiffened plates - Proceedings of the International Conference on Structural Engineering, Mechanics and Computation (SEMC) - Cape Town - South Africa, pp 1029 - 1036, 2001.
- CHUNG KIM YUEN, S., & NURICK, G. N., The significance of the thickness of a plate when subjected to localised blast load - 16th Symposium on Military Aspects of Blast and Shock (MABS16) - Oxford - UK, pp 491 - 499, 2000.
Published Conference Abstracts/Presentations
- CHUNG KIM YUEN, S, NURICK GN, & WITBEEN HL, The response of sandwich panels made of thin-walled tubes subjected to dynamic axial load, Impact Loading of Lightweight Structures Conference, Norway 17-19 June 2008.
- NURICK, GN, CHUNG KIM YUEN, S, JACOB, N, VERSTER, W, BWALYA, KD, & VARA, A. "Experiments of Steel Plates subjected to Large Explosive Loads", US-Africa Workshop on Mechanics and Materials, University of Cape Town, Cape Town, South Africa, 24-28 January, 2005.
- CHUNG KIM YUEN, S, LANGDON, GS & NURICK, GN. "Predicting tearing in blast-loaded quadrangular stiffened plates ", US-Africa Workshop on Mechanics and Materials, University of Cape Town, Cape Town, South Africa, 24-28 January, 2005.
- CHUNG KIM YUEN, S., & NURICK, G.N., "Modelling the deformation and tearing of thin and thick plates subjected to localised blast loads." South Africa's First International Symposium on Land Mine Countermeasures and Survivability, Pretoria, South Africa, September, 2003.
- JACOB, N., CHUNG KIM YUEN, S., NURICK, G.N., DESAI, S., & TAIT, D. "Quadrangular plates subjected to localised blast loads - an insight into scaling." South Africa's First International Symposium on Land Mine Countermeasures and Survivability, Pretoria, South Africa, September, 2003.
- CHUNG KIM YUEN, S., & NURICK, G. N., Deformation and tearing of uniformly blast-loaded quadrangular stiffened plates - Proceedings of the Solid Mechanics, Materials and Manufacturing conference (MMM)- Cape Town - South Africa, p 23 - 24, 2000.