Experimental investigation of joint with positive eccentricity in CFS truss

Due to technological restrictions, in the case of trusses made of CFS open cross-sections, positive eccentricities in the truss joints have become very frequent. Therefore studies concerning the load-bearing capacity of truss joints with positive eccentricity were undertaken. It was assumed that the resistance of cold-formed steel (CFS) open cross-section truss joints located on compression chords and with positive eccentricity is greater than that which results from hitherto known methods of steel structure dimensioning. In order to confirm the hypothesis, experimental studies were conducted. A series of 5 full-scale research models was subjected to destructive tests to determine the deformation forms and strains of the hat-section walls in the area of the eccentric joint. Forms of truss chord stability loss under compression and bending were identified. The course of research and analysis of results were described in the article. Than comparative analysis of the outcomes of the experimental tests and the results of analytical calculations carried out according to Eurocode standards was done, and the obtained results confirmed the usefulness of the undertaken research. The obtained results did not allow for explicit confirmation of the research hypothesis at this stage, but constituted the basis for validation of the numerical model which has been elaborated. Currently, the authors carry out a variety of numerical analysis.