Experimental Research On Static Behavior Of Thin-Walled Steel-Concrete Compositestructure Joint Under The Symmetric Loading

Thin-walled steel-concrete composite structure (TWSCS)is a new type structure which is composed of thin-walled steel plates,cold-formed thin-walled steel elements with concrete. The joints are the important parts in thin-walled steel–concrete composite structure system. It is more difficult of TWSCS then the steel structure or steel tube confined concrete structure ( STCC) to deal with the problem of the joints because the thickness of the steel plate of the columns is so much thinner that cannot be able to bear the tensile forces which come from the beams. So it is vitally important to find out a new type joint which is simply in construction details and reasonable in mechanic behavior.The paper presents five new types joints of thin-walled steel-concrete composite structure. JD-A, the columns and beams are connected by a steel tube with holes in the end of beams which can be used for the permanent formwork and to act as the partially or mainly longitudinal reinforcement; JD-B, it is the same as JD-A except without the steel tube; JD-C ,the beam and joints are made of reinforced concrete; JD-D ,the steel beam runs through the column; JD-E is of intend stiffness ring joint. 10 specimens of joints were tested under the symmetric loading, The joints JD-A,JD-B,JD-D were tested under two different shear span length in order to consider of the static behavior in different loading conditions.According to the test results, the static behavior including the failure model,ultimate bearing capability rigiding and ductility, for all different joints was obtained. At last, a practical calculation method for the ultimate bearing capability of the joints and some reasonable suggestions for design were also proposed.