Cable-stayed columns and their applications in building structures

Stayed columns have been used as architecturally expressive lightweight elements in buildings and tensioned-membrane structures. Their structural merits of reduced core size and enhanced compression strength even outweigh the architectural elegance. The main emphases of this paper, as such, is to reveal the structural benefits, the counter-intuitive structural behaviour, and to raise research interest in this special type of column through a series of case-studies. Structural behaviour of one and two-tier cross-arm cable-stayed columns are investigated for both symmetric and anti-symmetric modes. The use of prestressed tension elements (cables or rods as stays) along with a compression member (tube or solid core) and the pinching effect of cross-arms contribute to their anomalous structural behaviour. A Strength Enhancement Ratio (SER) is defined that evaluates the enhanced strength resulting from transforming a steel tube into a cable-stayed column. This provides a criteria for designers to determine when cable-stayed action should be considered as a useful and efficient means of providing the required strength to slender columns. The latter part of the paper presents various architectural applications of stayed columns through a series of case-studies.