The inelastic static pushover analysis has become a popular tool for evaluating the seismic capacity of structures. It is able of predicting the seismic force and deformation demands by accounting in an approximate manner for the inelastic redistribution of internal forces. Though approximate in nature and based on static loading, if properly used the pushover analysis can provide many significant insights into the structural behaviour and also put forward the design weaknesses that may be hidden in the elastic analysis. The main features of the conventional pushover analysis are well described in [1], where are also emphasized limitations and possible causes that may produce loss of accuracy of the method. A basic prerequisite for successful applications of the method is an adequate knowledge of the inelastic behaviour of structural elements. This is particularly true for those structures containing shear walls that, if not properly described, may render the results of the analysis completely meaningless.
In this work we show how, under appropriate hypotheses, one can introduce steel reinforcement into shear walls by appealing to a semi-analytical multi-scale approach. In particular, reinforcements are taken into account using an embedded beam approach, the usual conventional material behaviour, i.e. the the so-called parabolic-rectangular stress block for concrete and ideal elastic-plastic for steel as of Eurocode 2, and a fiber-free integration, that provides the exact solution for stress resultants over the cross section of the beam itself.
Representative numerical simulations are shown that illustrate the capabilities of the proposed approach, that allows one to carry out accurate nonlinear analyses of full-scale reinforced concrete structures with relatively reduced computational effort
