ABSTRACT
Upon recognition of the advantages of composite steel-concrete structures, solutions that integrate built-up cold-formed steel sections have become more prevalent in the last few decades. Some of the reasons for the increased interest in composite steel-concrete structures are that components of such systems are easy to manipulate, transport, and erect due to reduced weight. These advantages can be even more significant if the system is designed for demountability, reflecting the environmental impacts at the end-of-life of the system. This paper deals with a cold-formed steel-concrete composite floor system as part of the LWT-FLOOR project at the Faculty of Civil Engineering, University of Zagreb, Croatia. Cold-formed steel elements are built-up beams with back-to-back profiles such as flanges and corrugated webs. Cold-formed steel elements are connected by fast and productive spot-welding technology, while composite action between steel and concrete is realised through innovative demountable shear connections with structural bolts. The LWT-FLOOR system has numerous potential benefits, which will be investigated through experimental, numerical research with the support of probabilistic methods and, of course, life cycle analyses. This paper presents a practical application of integrating environmental impacts associated with the mentioned LWT-FLOOR system and the traditional composite structural floor system with hot-rolled steel beams. A comparative Life Cycle Assessment (LCA) of structural composite steel-concrete floor systems along with a Life Cycle Cost (LCC) are given. Impact analyses at different levels such as production and end-of-life were performed. This research reflects what makes a sustainable design with an example of a cold-formed steel-concrete composite system, which addresses the need for improved awareness of materials.
