Modelling Masonry as a Continuum: Finite Element Analysis using ABAQUS

The preservation of masonry structures, deeply intertwined with human history and culture, poses significant engineering challenges. Engineers work to ensure the safety and longevity of these structures through meticulous analysis of their structural integrity. However, conventional elastic theories often fall short in capturing the complexities of masonry, leading to potential oversights in assessment and accurate behaviour analyses. Jacques Heyman's critique of elastic theory highlights the need for alternative approaches, such as plastic theory, to analyse the behaviour of masonry structures. The evolution of analysis methods, from fracture mechanics to finite element models, reflects ongoing efforts to bridge the gap between theoretical frameworks and practical applications. In this dissertation the adoption of the Mohr-Coulomb (MC) model represents an innovative approach to modelling masonry as a continuum, offering a refined representation of its behaviour. Extreme values of cohesion and friction in the MC model mirror the characteristics of Normal Elastic No-tension (NENT) and Normal Rigid No-Tension (NRNT) models, providing a comprehensive understanding of masonry behaviour. Unlike other finite element models that require a huge number of unknown parameters, the MC model needs a minimal number, simplifying the analysis process. Through validation against established benchmark results and comparative analyses with Concrete Damage Plasticity (CDP) model and Piecewise Rigid Displacement (PRD) method, the MC model has demonstrated its effectiveness in capturing structural behaviour and collapse characteristics. For instance, in the analysis of the Torre del Piano, both Concrete Damage Plasticity (CDP) and MC models were evaluated. While the CDP model struggled to accurately specify collapse parameters, the MC model provided precise collapse multiplier values and fracture initiation points, showcasing its superiority in representing structural behaviour. Similarly, in the analysis of the Aqueduct de los Cinco Ojos under dynamic non-linear analysis, the two models predicted a similar behaviour. However, the CDP model exhibited computational advantages over MC when the dynamic analysis of large-scale masonry structures is concerned. An example of how the choice of FEA model can be selected depending on the desired outcome of the analyses is presented in Part B. The CDP model was adopted for the Beit El-Din case study exemplifying how, for efficiency, it can be reliably used to analyse large-scale 3D structures. While the MC model has proven its accuracy, ongoing research aims to enhance its computational efficiency to further optimise its performance in analysing masonry structures.