SHEAR CONNECTION IN COMPOSITE TRUSSES
Concentration of longitudinal shear flow above nodes of composite steel and concrete trusses is investigated. Numerical FE model was developed using ANSYS software. The non-linear 3D analysis modelling shear connection via spring elements was verified on two tests of composite trusses with span of 6 m, having perforated shear connectors of type developed at authors workplace. The experimental investigation is described in detail, followed by successful comparison with proposed FE analysis. The numerical model was used for pilot parametrical study of shear distribution at the connection between concrete slab and steel truss. The studied girder represented a secondary floor beam with Vierendeel panel at midspan under uniform loading. More than 20 variants of shear connections were studied, having various load-slip relationships obtained from previous research. The resulting distribution of shear flow within elastic behaviour of shear connectors showed distinctive peaks of the flow above nodes of the trusses. This may be important especially for connectors loaded in fatigue. Within plastic behaviour of shear connectors the plastic redistribution of shear flow followed depending on connectors load-slip relationship. The greater redistribution came about in partial shear connection, where also sufficient ductility of shear connectors was important (e.g.such as defined in Eurocode 4, i.e. δuk ≥6 mm), otherwise the resistance of the composite truss decreased significantly even if the strength capacity of shear connectors remained the same. In addition, further numerical investigation of bridge composite trusses of larger span was performed and results are presented with emphasis on local effects of longitudinal shear flow above truss nodes. The numerical results were compared with proposal given in Eurocode 4 and showed reasonable agreement with standard formulas. Finally suitability of standard formulas and other recommendations for practical design are discussed.
concrete steel composite shear force truss local effect
J Machacek M Cudejko
Czech Technical University in Prague, Czech Republic
国际会议
The 9th International Conference on Steel Space & Composite Structures(第九届国际钢材、空间结构、组合结构会议)
烟台·北京
英文
571-579
2007-10-10（万方平台首次上网日期，不代表论文的发表时间）