Experimental investigations on composite stub columns: hollow sections with embedded solid core made of HSS

A new composite column system using a solid core and an encasing jacket made from (ultra‐)high‐strength structural steel filled with concrete is presented in this paper that can serve as a promising alternative to prefabricated reinforced concrete columns from an economic and constructive point of view. Within the scope of a research project, this topic is being investigated in more detail by means of numerous experimental and theoretical investigations to enable the use of (ultra‐)high‐strength steels in the future. In this article, stub column tests were carried out to assess the resistance to pure compression and to gain insights into the structural performance of this new composite column system. Novel measurement techniques are used to evaluate the different normal force bearing components of the steel core, the hollow steel section, and the filled concrete over the entire loading process. A clear dependence of the load‐bearing behaviour on the cross‐sectional shape and the load introduction form (full‐surface load introduction vs. load introduction via the core surface) was observed.