doi:10.3850/978-981-08-6218-3_key-7
Ultra-High Strength Concrete Filled Columns for Highrise Buildings
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Professor Richard Liew Department of Civil Engineering National University of Singapore Singapore. cveljy@nus.edu.sg |
Biography
Richard Liew is a Professor and the Programme Director of Hazard, Risk and Mitigation in the Department of Civil Engineering at the National University of Singapore.
Richard’s research covers a broad area of design and behaviour of steel and composite steel-concrete structures, fire and blast engineering, as well as methods of nonlinear analysis and applications to design.
Richard is a registered professional engineer in Singapore and a Chartered Engineer in the United Kingdom. He is the author of over 250 publications and a number of design guides, several of which are used daily by practicing engineers. He is the Immediate Past President of the Singapore Structural Steel Society.
Richard has a wide range of experience on national and international technical committees and industry groups and has been involved in the development of the National Annexes for Eurocodes 3 and 4. He has been active in providing specialist advisory services to major construction projects in Singapore.
Abstract
This paper presents the investigation work on steel tubular columns infilled with ultra-high strength concrete (UHSC) of compressive strength close to 200MPa. Compression tests were carried out on eight UHSC filled circular composite specimens, including four infilled single-tube columns and four infilled double-tube columns. Different mix proportions and sizes of ordinary coarse aggregates were adopted to investigate their effect on the performance of UHSC filled tubular columns. It is found that the use of ordinary coarse aggregates had no significant effect on the strength and ductility, but they could reduce the mix proportion of binder and thus reduce the cost of producing the UHSC. The ductility of axially loaded UHSC filled steel tubular columns was assessed based on the residual strength in the post buckling range. Test results indicate that the columns with higher steel contribution ratio would have higher residual strength. Eurocode 4 method is found to provide reasonable estimation of the compression resistance of circular columns infilled with UHSC if the enhancement due to confinement effect is not considered. Furthermore, it is recommended that the minimum limit of steel contribution ratio should be at least 0.3 to achieve sufficient ductility performance.
