STRESS-STRAIN STATE AS THE IMPLEMENTATION OF COLLAPSE AND SHEAR IN A BOLTED-WELDED JOINT

The results of the studies are presented which is an extension of the earlier authors’ work of combined bolted-welded joints for building steel structures. Data on the parameters of the stress-strain state of finite-element models of physical specimens of bolted, welded and bolted-welded connections are given. These specimens are manufactured and are being prepared for testing. There are some special features of design of physical specimens and numerical models: the conditions which have been created for realization of limit state, conditioned by crushing of bolt edge of a hole in a thinner piece and its consequent breaking (poking out). Subsequently, it is supposed to compare data on the parameters of the numerical models and physical samples. Considering computer modeling of bolted-welded specimens, it is assumed that welds are made (imposed) after a finite-element model of the bolt connection has been loaded to a certain part of its bearing capacity according to the crushing criterion. Such conditions correspond to the operation of a bolted joint reinforced at partial unloading by welds. Thus, it is assumed that the bolted joint will be deformed largely before it is reinforced with welds. According to the authors' hypothesis, it will create favourable conditions for joint operation of the bolted joint and welds during its loading after reinforcement. The generally obtained numerical simulation data confirm the above hypothesis on the possible joint operation of welds and bolted joint, in which the limiting state in terms of buckling is realized and which is reinforced by partial unloading with welds.