Abstract

Reinforced brick masonry has experienced only scarce use as a fully structural material due to, among other reasons, the lack of design criteria and calculation tools allowing a scientific, but also practical, engineering approach to design and assessment. Aiming at contributing to a more widespread use of this material, a simplified method for the ultimate analysis of reinforced masonry arches and cylindrical vaults, based on the lower-bound theorem (or static approach) of plasticity, has been developed. This approach has been satisfactorily validated by comparison with experimental and numerical results obtained by more accurate numerical models.

Abstract

The present paper investigates the response of masonry structural elements with periodic texture adopting an advanced multiscale finite element model, coupling different formulations at the two selected scales of analysis. At the macroscopic structural level, a homogeneous thick shell is considered and its constitutive response is derived by the detailed analysis of the masonry repetitive Unit Cell (UC), analyzed at the microlevel in the framework of the threedimensional (3D) Cauchy continuum. The UC is formed by the assembly of elastic bricks and nonlinear mortar joints, modeled as zero-thickness interfaces. The Transformation Field Analysis procedure is invoked to address the nonlinear homogenization problem of the regular masonry. The performance of the model in reproducing various masonry textures is explored by referring to an experimentally tested pointed vault under different profiles of prescribed differential settlements. The structural behavior of the vault is studied in terms of global load-displacement curves and damaging patterns and the numerical results are compared with those recovered by detailed micromechanical analyses and experimental evidences.

Abstract

Practising structural engineers working with historic masonry structures need access to further developed methods to analyse and assess the structural behaviour of masonry vaults. The aim of this study is to evaluate methods to analyse vaulted masonry structures and to develop a methodology for the application of suitable methods to the work of practising structural engineers. A secondary aim is to use the methods studied to analyse and assess the structural behaviour of three Swedish church buildings of different types and with vaulted structures. The churches are Gökhem church, a small parish church built in the 12th century, and the Lund cathedral, also built in the 12th century; both originally in the Romanesque style but with later alterations. The third church is St Johannes church in Stockholm, built in the neogothic style in the late 19th century. The methods used are parametric graphic statics of thrust line analysis and Thrust Network Analysis (TNA), both based on funicular analysis. The results show the strength of using such methods to assess and evaluate the structural behaviour of historic vaulted masonry structures. They provide a pedagogical description of the structural behaviour of masonry vaults and the conditions that affect their load-carrying capacity. Another result is the implementation of a method to perform the analysis in a feasible and effective way. For the analysed church buildings, the results provide an understanding of their structural behaviour and clearly show how different variables affect the magnitude and impact of the thrusting force. Thrust Network Analysis has great potential to become a very effective method to perform advanced 3d analyses of masonry vaults but needs to be developed in order to enable “best fit solutions” to map the thrust network to the shape of the existing vaults. Such methods are under development.

Abstract