https://hdl.handle.net/10481/19573 2026-04-18T03:47:23Z 2026-04-18T03:47:23Z Fernández Ruiz, Manuel Alejandro Hernández Montes, Enrique Gil Martín, Luisa María https://hdl.handle.net/10481/107202 2025-10-21T07:04:19Z

From octagonal connection graphs belonging to the Z-Octahedron family to new tensegrity structures Fernández Ruiz, Manuel Alejandro; Hernández Montes, Enrique; Gil Martín, Luisa María A tensegrity family is a group of tensegrity structures that share a common connectivity pattern. The Octahedron, the Z-Octahedron, and the X-Octahedron families are examples of these groups found in the literature. In this work, a new graphical representation of the members of the Z-Octahedron family based on octagonal cells is presented. These new elementary cells are composed of eight nodes and two struts. In addition, a new member of the family is introduced: the Z-triple-expanded octahedron. New tensegrity structures from the Z-Octahedron family are obtained by modifying the connectivity pattern of the elements that make up the octagonal cell. Several element groupings have been considered in order to find different equilibrium configurations. The values of the force density or force:length ratio that lead to stable and super-stable tensegrity forms have been computed analytically. It has been proved that the Z-Octahedron family is a good source of new tensegrity forms.

Gil Martín, Luisa María Fernández Ruiz, Manuel Alejandro Hernández Montes, Enrique https://hdl.handle.net/10481/107201 2025-10-21T06:57:43Z

Mechanical Characterization and Creep Behavior of a Stone Heritage Material Used in Granada (Spain): Santa Pudia Calcarenite Gil Martín, Luisa María; Fernández Ruiz, Manuel Alejandro; Hernández Montes, Enrique Santa Pudia calcarenite was one of the most commonly used building materials in the construction of historical buildings in the city of Granada (Spain). As a result, Santa Pudia calcarenite has been mainly studied from a petrographical point of view in previous works. In this work, the mechanical properties of Santa Pudia calcarenite are studied. The main mechanical properties (compressive strength, elastic modulus and Poisson’s ratio) were determined using the corresponding tests. Samples of Santa Pudia calcarenite were heated at 550 °C to study the effect of high temperatures on its compressive strength. Two different cooling methods were considered: air-cooling and water-cooling. Stress–strain curves of heated and non-heated samples were obtained from uniaxial compression tests. Creep is of great importance in the long-term structural assessment of historical buildings. To study the creep behaviour of Santa Pudia calcarenite, samples were subjected to uniaxial compressive tests at constant stress until the stabilization of the recorded strains was reached. Different rheological models were adjusted to the experimental results to simulate the long-term behaviour of the material studied. The instantaneous response to additional loadings on the samples (maintaining the long-term loading and deformation) were also studied. Results show that a Santa Pudia calcarenite specimen subjected to dead loads will suffer a higher instantaneous deformation against a sudden load than a non-preloaded specimen. This degradation effect can be particularly important in the case of a seismic evaluation of historical buildings.

Hernández, Luisa Fernández Ruiz, Manuel Alejandro Gil Martín, Luisa María https://hdl.handle.net/10481/107197 2025-10-21T06:17:30Z

Influence of the level of connectivity on the members of the Octahedron and X-Octahedron families of tensegrities Hernández, Luisa; Fernández Ruiz, Manuel Alejandro; Gil Martín, Luisa María Tensegrity structures based on topological patterns have been developed greatly in recent years. Tensegrities obtained from the same pattern are said to belong to a family. Two examples of tensegrity families are the Octahedron and the X-Octahedron, whose members are composed of rhombic and X-rhombic cells, respectively, which are collected in three groups. The general connectivity pattern of both families consists of three levels of connectivity. This work analyzes the influence of the reduction of the level of connectivity on the members of both families. The connection graphs corresponding to different levels of connectivity are defined based on the new concept of “twin tensegrities”. Analytical computations have been performed to determine the force:length ratios that satisfy equilibrium, stability, and super-stability conditions. In addition, the mathematical sequence that follows the ratio between the force:length ratio of struts and cables of the X-Octahedron family that leads to a super-stable equilibrium configuration is presented. The new tensegrities obtained in this work also belong to the Octahedron and X-Octahedron families and could have promising engineering applications such as modular constructions.

Hernández-Montes, Enrique Jalón, María Lourdes Rodríguez-Romero, Rubén Chiachío, Juan Compán-Cardiel, Víctor Gil-Martín, Luisa María https://hdl.handle.net/10481/107196 2025-10-21T06:14:32Z

Bayesian structural parameter identification from ambient vibration in cultural heritage buildings: The case of the San Jerónimo monastery in Granada, Spain Hernández-Montes, Enrique; Jalón, María Lourdes; Rodríguez-Romero, Rubén; Chiachío, Juan; Compán-Cardiel, Víctor; Gil-Martín, Luisa María The deterioration of Cultural Heritage assets caused by the natural hazards is a pressing issue in many countries. Therefore, reliable models based on the large-scale structural response of the assets is key to assess their resilience. However, reliable models such as large and detailed Finite Element (FE) models, require a large number of data and input parameters. This paper proposes a Bayesian learning approach to identify the main parameters of a FE model with quantified uncertainty based on ambient vibration data. As a novelty when compared with other Bayesian structural parameter identification methods from ambient vibration data, here the likelihood function is formulated in a principled way considering information from both frequencies and modes using a probabilistic version of the Modal Assurance Criterion for the modes. This method is embedded into a parameterised computational model to automate the simulation process, and a real case study for a sixteenth century heritage building in Granada (Spain) is presented. The results show the suitability and effectiveness of the proposed Bayesian approach in identifying the most plausible values of the uncertain model parameters in a rigorous probabilistic way, but also in obtaining the modelled frequencies and the modal assurance criterion values with quantified uncertainty.

Fernández Ruiz, Manuel Alejandro Hernández Montes, Enrique Gil Martín, Luisa María https://hdl.handle.net/10481/70922 2021-10-18T08:47:55Z

Topological Design of Tensegrity Structures Fernández Ruiz, Manuel Alejandro; Hernández Montes, Enrique; Gil Martín, Luisa María Tensegrity structures have developed greatly in recent years due to their unique mechanical and mathematical properties. In this work, the topology of the Octahedron family is presented. New tensegrity structures that belong to this family are defined based on their topology. As an example, the eleven-time-expanded octahedron is shown, a super-stable tensegrity formed by 12288 nodes, 6144 struts, and 24576 cables (the largest super-stable tensegrity reported in the literature in terms of number of nodes, cables, and struts so far). The values of the force:length ratios which satisfy the super-stability conditions have also been determined based on the topology of the Octahedron family. Consequently, the computational cost of the process of determining a suitable prestress state and its corresponding equilibrium shape (a process called form-finding) is significantly reduced. The members of the Octahedron family could have promising engineering and bioengineering applications. Artículo en revisión en una revista científica desde el 18 de Octubre de 2021