A numerical methodology for the cross-sections analysis of steel-concrete composite beams with partial shear connection

Resumo

The present work aims at the implementation and validation of a numerical formulation based on the
Strain Compatibility Method (SCM) for the calculus of the cross-section’s resistance capacity of steel-concrete
composite beams with partial shear connection. It is developed, here, a strategy for capturing the longitudinal
deformations at all cross-section’s points. Thus, the section’s discretization, isolating the steel profile from the
concrete slab, is necessary. In this context, the classic SCM is modified by the insertion of one explicit degree of
freedom at the steel-concrete interface, corresponding to a discontinuity on the deformations field, allowing the
longitudinal sliding between the steel profile and the concrete slab. Therefore, the axial force dismemberment is
done, on which a part is absorbed by the profile and the other part by the slab. By equilibrium, the difference
between the slab’s and profile’s forces generates a shear force at the connection and, using the Ollgaard’s model,
the longitudinal sliding at the contact point, is found. Assuming the plane cross-section theory, a single curvature
is assigned to both constituents of the section. Thereby, it is done the construction of the moment-curvature
relationship using the standard Newton-Raphson method combined with continuation strategies aiming to capture
the hardening and softening of the materials over the loading historic of the section. However, in order to implement
the analysis, exclusively, in the cross-section, a fixed degree of freedom is assigned to it. For the validation of the
proposed numerical formulation, the obtained results are confronted with numerical data available in the literature.