Экспериментально-теоретические исследования стальных ферм покрытия легкоатлетического манежа в г. Тюмени

The object of study is large-span steel trapezoidal truss with a triangular lattice made of paired hot rolled corners. The need for full-scale trusses testing by static loads caused by the previously performed strengthening of the truss joints with the upbuilding of gusset plates. The aim of research was receiving and comparison of experimental and calculated data about trusses deformations, assessment of their load-carrying ability and reliability. Testing trusses by static loads performed by uploading a free weights road plates and base blocks on block of two trusses, bracings, struts and girders. Static calculations of trusses performed in three variants calculation schemes: with articulated conjugation chords, braces and struts together, with a rigid chords and the adjacent hinged braces and struts and with modeling of the size and hardness of gusset plates. The comprehensive studies revealed the influence of the size and hardness of gusset plates on the stress-strain state and residual deformations of trusses, experimental and theoretical deflections of structures were studied, residual deformation of trusses were defined as a result of field experiments, calculations of the bearing capacity of structures were performed. Large size and rigidity of gusset plates led to the formation of large bending moments and overload of upper zones of truss by 16,8 %. According to the results of studies trusses were considered unusable for further usage due to large permanent deformation of structures, as in the preliminary, and in the main loadings by static loads.