The observation of old construction works confirms that masonry domes can withstand tensile hoop stresses, at least up to a certain level. Here, such tensile resistance, rather than assumed as a property of the bulk material, is attributed to the contact forces that are developed at the interfaces between interlocked blocks under normal pressure, specified by Coulomb's friction law. According to this rationale, the aspect ratio of the blocks, as well as the bond pattern, becomes of fundamental importance. To investigate the complex assembly of blocks, supposed rigid, we present a non-smooth contact dynamic analysis, implemented in a custom software based on the Project Chrono C++ framework and complemented with parametric-design interfaces for pre- and post-processing complex geometries. Through this advanced tool, we investigate the role of frictional forces resisting hoop stresses in the stability of domes, either circular or oval, under static and dynamic loading, focusing, in particular, on the structural role played by the underlying drum and the surmounting.

A Non-Smooth Contact Dynamic (NSCD) formulation is used to analyze complex assemblies of rigid blocks, representative of real masonry structures. A model of associative friction sliding is proposed, expressed through a Differential Variational Inequality (DVI) formulation, relying upon the theory of Measure Differential Inclusion (MDI). A regularization is used in order to select a unique solution and to avoid problems of indeterminacy in redundant contacts. This approach, complemented with an optimized collision detection algorithm for convex contacts, results to be reliable for dynamic analyses of masonry structures under static and dynamic loads. The approach is comprehensive, since we implement a custom NSCD simulator based on the Project Chrono C++ framework, and we design custom tools for pre-and post-processing through a user-friendly parametric design software. Representative examples confirm that the method can handle 3-D complex structures, as typically are architectural masonry constructions, under both static and dynamic loading.

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The Miura Ori is a mechanism composed by a polyhedral deployable surface. It has favorable qualities from engineering prospective that lead the growing interest on it. The present work focuses on its transmission of motion. The mechanism can be represented by spherical 4 bar linkages, and on this account a simple and effective mobility formula is presented. The mechanism having a number of excessive rigid members, it is also possible to remove all or some of them, variously arranged. The changes are included in the calculation of allowable mobility of the system. The resulting tool can be directly used for the design of deployable Miura Ori surfaces with customized shape.

This paper concerns non-developable folded plate structures. It presents the translational method; a design technique that creates threedimensional non-developable systems that can approximate any surface made by translating a generic curve along another generic curve. The continuous folding process is guaranteed by keeping the value of dihedral angles throughout the structure constant at each phase. Once solved the kinematic constraints, the lengths of sides are opportunely varied to approximate any translational surface. The translational method allows for free setting of the target curvature, the approximation span, and the sharpness of the plates.