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The evaluation of damage mechanism and the failure of dry-stone masonry structures subjected to seismic load is one of the most important aspects of seismic assessment of existing masonry buildings. Discontinuities between the blocks, their mechanical interaction, large displacement and rotation are the main causes of degradation and collapse of these structures. This paper presents the application of the combined finite-discrete element method (FDEM) in the analysis of 3D dry-stone masonry structures which is able to capture such mechanisms and structural damage both at joint and at block level. Moreover, the proposed approach includes friction forces based on Coulomb-type of law accounting for friction effects across dry joints and open cracks, in order to correctly simulate the mechanical behaviour of dry-stone masonry. The capabilities of presented approach are demonstrated in a series of numerical tests, starting with sliding and rocking of single blocks, examination of dry joints shear behaviour, walls subjected to in-plane and out-of-plane load, and finally the simulation of the simple spatial stone masonry structure. [ABSTRACT FROM AUTHOR]

A great number of buildings which are classified as cultural heritage are historic structures made of stone blocks with dry joints. Some of them, which were originally built with mortar in the joints, have experienced mechanical degradation over time and the behaviour of these structures becomes similar to those made of dry stone masonry. Most of these structures have been damaged due to seismic activity. With the aim of increasing their resistance, many of dry stone historical structures were further strengthened by clamps and bolts. In order to evaluate the resistance of these structures, experimental investigations of the behaviour of existing stone masonry structures is very important. This paper presents experimental investigations of the behaviour of the model of stone masonry structure Protiron in the Peristyle square of the Diocletian’s Palace in Split, Croatia, under the seismic excitation. The Protiron was originally built at the turn of the fourth century only from stone blocks and bolts. At the beginning of the 20th century it was strengthened with clamps. A physical model of the Protiron for experimental shaking table testing was constructed in scale 1:4. The testing was performed on the 5×5 meters seismic shaking table at the Dynamic testing laboratory of the Institute of Earthquake Engineering and Engineering Seismology (IZIIS) in Skopje, Macedonia. The testing consisted of several phases: (1) definition of dynamic characteristics of the model; (2) seismic testing in linear range; (3) seismic testing in non-linear range by representative earthquake until failure of the model. The tests provided a clear insight into the seismic resistance and behaviour of the system, the mechanism of damage and failure under intensive tests, especially in the efficiency of the connecting elements (clamps) between the masonry units (stones), which had a special role in increasing the seismic energy dissipation and protection of the structure from collapse. [ABSTRACT FROM AUTHOR]

This paper presents a new numerical model for a static and dynamic analysis of thin plate structures based on the combined finite–discrete element method (FDEM). The model uses three-noded triangular finite elements taking into account linear-elastic material behaviour, finite rotations, finite displacements and small strains. The model is implemented into the open source FDEM package ‘Yfdem’. Performance of the new numerical model was demonstrated on simple benchmark tests by a comparison with known analytical and numerical results. [ABSTRACT FROM AUTHOR]

This paper presents a new robust finite-discrete element numerical model for analysis and prediction of the collapse of dry stone masonry structures strengthened with steel clamps and bolts. The model includes fracture and fragmentation of the blocks as well as a cyclic behaviour, yielding, stiffness degradation, failure and the influence of pulling out of the clamps and the bolts from the stone block. The developed model can be used for the estimation of the seismic resistance of historical dry stone masonry structures reinforced with steel clamps and steel bolts, which is very important for the structures classified as cultural heritage. [ABSTRACT FROM AUTHOR]

This paper presents a new numerical model based on the combined finite–discrete element method for the analysis and prediction of the collapse of masonry structures. The model consists of a new numerical model in a finite element and a new material model in an interface element which simulate the behaviour of the mortar joints and unit-mortar interface. The comparison between the numerical results obtained by this model and the available numerical and experimental results shows high accuracy in predicting the behaviour of the masonry structure through the entire failure mechanism from the continuum to the discontinuum. [ABSTRACT FROM AUTHOR]

Abstract: This paper presents the performance of a combined finite-discrete element method (FEM/DEM) for the material and geometric non-linear analysis of the structural response of dry stone masonry structures under monotonic, cyclic and seismic loads. In the proposed modelling approach each stone block is modelled as a discrete element which is discretized by triangular finite elements. Material non-linearity including fracture and fragmentation of discrete elements as well as cyclic behaviour during dynamic load are considered through contact elements which are implemented within a finite element mesh. The numerical analysis based on experimental test data has been carried out to simulate the main features of dry stone structures. The performed analysis shows high accuracy of the numerical results in comparison with the experimental ones and demonstrates the potential of the FEM/DEM method for realistic modelling of the response of dry stone masonry structures. [Copyright &y& Elsevier]

• A new numerical model for the nonlinear analysis of shell structures is presented. • The model is based on rotation free triangular finite elements. • The model has been implemented into the finite-discrete element package Y-FDEM. • The model has been tested on the benchmark problems. • The model proved to be suitable for the analysis of thin shell structures. The paper presents a new numerical model for analysis of thin shell structures taking into account geometrical and material nonlinearity, finite displacements, finite rotations and finite strains. The model is based on three-noded rotation-free triangular finite elements and is implemented in the open source Y-FDEM software package based on the Combined finite-discrete element method (FDEM). Material nonlinearity was implemented considering the von Mises flow condition, the Levi-Mises flow rule, and the Johnson-Cook constitutive law. The efficiency of the model was demonstrated on the benchmark problems by comparing numerical results with known analytical or other numerical results. [ABSTRACT FROM AUTHOR]

This paper reviews several computational aspects of the combined finite–discrete element method related to the modelling of plane reinforced concrete progressive fracturing. It discusses especially the ability of the presented numerical model, extended with a new model of reinforcing bar, to simulate the behaviour of the reinforced concrete structure through the entire failure mechanism from the continuum to the discontinuum. It also presents similar topics, including the tracing of the progressive collapse due to impact loading and the intensive seismic excitation. [ABSTRACT FROM AUTHOR]