Dimensionamento e análise de custo de vigas mistas de aço-concreto com stud bolt e conector treliçado

Abstract

Steel-concrete composite beams are structural elements consisting of a reinforced concrete slab on the upper flange of a steel profile. The connection between these two elements is made using shear connectors. Among the most varied types, the stud bolt. However, this has a relatively high cost, often making the use of mixed systems unfeasible. In view of this, much research seeks to develop alternative connectors that have low cost and that guarantee adequate performance for composite beams in the face of requests, among which the lattice connector can be highlighted. In this sense, this work aims to compare the costs of applying stud bolt and truss connectors to composite beams. The formulations in NBR 8800:2008 and in the work of Lima (2021) were used to size the beams. With this, it was possible to obtain the number of stud bolts and truss connectors. Finally, the composition of inputs for each connector was prepared and, therefore, the unit cost of both was determined. It was found that the unit cost of the lattice connector was approximately 46% lower compared to the stud bolt. Furthermore, the final cost of truss connectors for the structure was approximately 51% lower than stud bolts. This reveals that the execution of composite beams with a lattice connector presents good economic viability.