Research on the Flexural Performance of One-Way Flat Top-Chord-Free Open-Web Truss Composite Floors

A novel floor system called one-way flat top-chord-free open-web truss composite floor is proposed in this paper. This system innovatively removes the steel top chords and diagonal web members of a conventional steel truss composite floor and uses mound blocks as vertical webs， which are connected to the steel bottom chords and the concrete slabs with studs. By adopting the assumption of mound block continuum， differential equations were established and solved. Under the condition of two-point loading， the internal forces， ultimate bearing capacities， and the elastic deformation formulas were obtained and verified by experimental data. Parametric analysis of elastic deflection was also conducted. The results showed that the ultimate bearing capacity of this floor system could not be determined by the conventional method for composite beams， which relies on the bearing capacity of a single cross-section. Instead， various failure modes and corresponding bearing capacities of different components should be considered. The deflection calculation formula derived in this paper could accurately calculate the elastic deformation of the composite floor system.