Experimental and numerical assessment of stayed steel columns

Stayed steel columns may be used as compression-resisting members of a structure presenting high slenderness ratios and fast erection requirements. The system is able to sustain a wide range of load levels and lengths with economic and reliable structural solutions. Although this structural solution dates back from the 1960s its structural behaviour is not fully understood. This fact motivated a study of the system structural behaviour by means of an experimental program followed by finite element simulations aiming to determine the most efficient structural geometries and the corresponding steel ties pre-stress force magnitudes. A series of full-scale tests were executed in 12 m pre-stressed steel columns with a 90 mm diameter. Some of the main contributions of the current study are related to the conception, development and execution of new tri-dimensional full-scale tests and the development of a finite element model calibrated against these experiments. An extensive parametric analysis based on the calibrated finite element simulation was also performed focusing on the most significant parameters that could affect the structural response, i.e., column length and diameter, pre-stress force magnitude, among others. The test and numerical results will certainly contribute to the development of updated design procedures and formulae to be introduced in future structural design codes.