Author(s)

I. Mura

Abstract

An analytical approach is proposed for the calculation of axial and bending secant stiffness properties of a masonry wall or column. In accordance with experimental results, a non-linear (parabolic) stress-strain relationship for compressed masonry is adopted in the analysis. Tensile strength, which is small compared to compressive strength, is neglected. A linear strain distribution is assumed in the analysis. Keywords: secant stiffness, masonry walls, non-linear constitutive law, notension material, numerical methods. 1 Introduction In the formulation of a method for calculating the behaviour of a masonry structural element, it is first necessary to define its constitutive law. The various proposals that have thus far been formulated and adopted in theoretical studies differ to a certain extent (Frish-Fay [1], La Mendola and Papia [2], Powell and Hodgkinson [3], Priestley and Elder [4], Pume [5], Sawko and Rouf [6]). The dispersion of experimental results and the deformation curves subsequently adopted derive from an objective factor: it is essentially attributed to the dispersion of the characteristics of the different kinds of masonry involved. The schematization of the constitutive law with a second-degree parabolic trend and the vertex corresponding to the maximum strength value appears to be the most generalized one. Such a schematization indeed describes the behaviour of brick walls and concrete walls [3, 4] and is thus the one that will be used in this study. Having stated this, it is known that the first essential step to be taken in performing an analysis of masonry structures with numerical methods is the

Keywords

secant stiffness, masonry walls, non-linear constitutive law, notension material, numerical methods.