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The knowledge of contact forces in teeth surfaces during mastication or para-functional movements can help to understand processes related to friction and wear of human dental enamel. The development of a numerical model for analysis of the occlusal contact between two antagonistic teeth is proposed, which includes three basic steps: the characterisation of the surface roughness, its homogenisation using an assumed distribution function and the numerical determination of the resulting forces. Finite element strain results for the main different asperities are statistically combined, deriving the predicted macroscopic behaviour of the interface. Axisymmetric and 3D numerical models with an elasto-plastic constitutive law are used to simulate micro-indentations and micro-contacts, respectively. The contact is allowed to occur locally in planes not necessarily parallel to the surface's mean plane, a problem for which there is no analytical solution. The three identified parameters, homogenised surface hardness (3.68 GPa), surface yield stress (3.08 GPa) and static friction coefficient (0.23), agree with the experimental values reported in the literature.

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In this paper, a critical comparison of two of the most common methods for the analysis of masonry vaults up to collapse is carried on. Innovative 2D Discrete Element (DE) and Finite Element (FE) models have been adopted aiming at capturing the main features of masonry single curvature structures mechanical behavior. Two numerical strategies are adopted: a discrete element model and a continuous homogenized model. The first approach provides an estimate of the collapse load and failure pattern of masonry based on ad-hoc implemented algorithm. The second approach is formulated in the framework of multi-surface plasticity and implemented in a FE code for the path-following non-linear analysis of masonry wall described as continuous anisotropic plate. The two numerical approaches are adopted to reproduce the Experimental Campaign of a full-scale Catalan vault with buttresses and backfill, statically loaded at 1/3 span. The failure modes and the crack patterns obtained by the proposed models are compared between them and with that observed in the experimental test as well as the load-displacement response curves. Both the proposed models efficiently capture the behavior of the vault and, in particular, the backfill deformation and load-spreading effect, hinges position and formation order.

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The paper presents recent results of an ongoing collaborative research project focused on modelling the Kurpsai water dam in Kyrgyzstan. The research team includes scientists and engineers from the USA, Kyrgyzstan, and Uzbekistan. This water dam was selected for modelling because of the recent installation of an extensive network of various sensors aimed at monitoring its performance under seasonal changes, ambient vibration, and seismic excitation. The installed instrumentation network includes the following sensors: (1) a set of fiber-optic strainmeters and temperature meters, (2) a set of velocimeters for seismic monitoring, and (3) a set of GNSS receivers to measure absolute static displacements. A 3D model of the water dam was generated based on a utilization of the finite element approach. As a starting point the water dam’s concrete was assumed to be elastic material. The latter assumption is considered acceptable, because (as of today) only responses to relatively small excitations were measured by the sensors. The actual responses of the dam were compared to that of the finite element model to achieve a close correlation with each other. Resonant frequencies of the water dam and its vibrational modes were estimated from the model. In the next phase of the project, the research team is planning to update the geometry of the model based on laser scanning that will be conducted this year. Local anomalies (bulging areas, cracks and so on) of the water dam will be studied via an analysis of point clouds collected by the laser scanner. The fully developed model will be used in an extensive numerical study to predict the dam’s performance and its response to strong seismic events and other hazards.

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