Behaviour of a Space Inverted Triangular Steel Truss

Abstract

Behaviour of the inverted triangular truss, which is widely used as a bridge girder, was investigated analytically and experimentally. Cold-formed square hollow cross-sections of steel grade S355J2H with dimensions 80 mm × 4 mm, 90 mm × 4 mm and 40 mm × 4 mm were selected for the top and bottom chords and bracing elements of the truss with 12.56 m span, correspondingly. Five FEM models were developed using software Dlubal RFEM. The main specific feature of the models is the difference in modelling of joint behaviour considering plastic behaviour and stiffness of truss connections. It was shown that the FE model of the truss where the members were modelled by the truss type finite elements and the joints modelled by the shell type ones allows predicting behaviour of the truss with precision of up to 3.9%. It was shown that precision of the suggested FEM model grows 4.36 to 4.62 times in comparison with the traditional FEM models where the members were modelled by the truss finite elements with the pinned and rigid joints in case of plastic joint behaviour. Precision of the suggested FEM model is identical to that of the traditional FEM models regarding the case of elastic joint behaviour.

Experimental Case Studies about Uniplanar SHS Joints with Full-Overlapped Top Connection

“…Podkoritovs et al [9] carried out numerical studies concerning three-dimensional truss joints made of squared hollow section joints. As part of a truss, the braces were either in compression or tension.…”

“…The model is comparable to the SHS profile analyzed in this paper. The dimensions of the cross sections (RO 48.0 × 2 mm and RO 48.0 × 2.8 mm [9]) and the analysis process are similar to the SHS model. So, there is one circular profile with the same thickness as the squared profile.…”

“…Overall, there is a pronounced difference in stress distribution patterns of specimens made with intermediate plates and the ones connected directly. Podkoritovs et al [9] performed numerical and experimental studies concerning three-dimensional truss joints made of squared hollow section joints. The joint is comparable to the standard defined multiplanar K-joint.…”