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The purpose of this research is to establish a robust numerical framework for the calibration of macroscopic constitutive parameters, based on the analysis of polycrystalline RVEs with computational homogenisation.

This framework is composed of four building-blocks: (1) the multi-scale model, consisting of polycrystalline RVEs, where the grains are modelled with anisotropic crystal plasticity, and computational homogenisation to link the scales, (2) a set of loading cases to generate the reference responses, (3) the von Mises elasto-plastic model to be calibrated, and (4) the optimisation algorithms to solve the inverse identification problem. Several optimisation algorithms are assessed through a reference identification problem. Thereafter, different calibration strategies are tested. The accuracy of the calibrated models is evaluated by comparing their results against an FE2 model and experimental data.

In the initial tests, the LIPO optimiser performs the best. Good results accuracy is obtained with the calibrated constitutive models. The computing time needed by the FE2 simulations is 5 orders of magnitude larger, compared to the standard macroscopic simulations, demonstrating how this framework is suitable to obtain efficient micro-mechanics-informed constitutive models.

This contribution proposes a numerical framework, based on FE2 and macro-scale single element simulations, where the calibration of constitutive laws is informed by multi-scale analysis. The most efficient combination of optimisation algorithm and definition of the objective function is studied, and the robustness of the proposed approach is demonstrated by validation with both numerical and experimental data.

This study aims to propose and numerically assess different ways of discretising a very weak formulation of the Poisson problem.

We use integration by parts twice to shift smoothness requirements to the test functions, thereby allowing low-regularity data and solutions.

Various conforming discretisations are presented and tested, with numerical results indicating good accuracy and stability in different types of problems.

This is one of the first articles to propose and test concrete discretisations for very weak variational formulations in primal form. The numerical results, which include a problem based on real MRI data, indicate the potential of very weak finite element methods for tackling problems with low regularity.

Adaptive load-bearing structures pursue the approach of saving mass within a load-bearing structure by adding external energy, thus saving materials and resources. This paper provides an overview of current research developments and shows some examples of existing prototypes.

First, basic terms and definitions from the research field of adaptive structures are introduced. After a brief historical insight, the numerical methods and prototypes used are presented as examples. The paper concludes with a summary of the state-of-the-art and open questions.

The current state of the art shows that the idea of adaptive structures offers great potential for more sustainability and resource efficiency in the construction industry. However, it also shows that research is still at the basic stage and that there are still some gaps in research.

The implementation of adaptive load-bearing structures is just one of many different approaches to greater sustainability in the construction sector. The issue of adaptive structures is a highly interdisciplinary field of research. The following paper is a literature review intended to summarize and critically evaluate the state-of-the-art research in this field. In the final section, some open questions are addressed, indicating that this research topic is still evolving.

During a fall, a significant part of the major forces is absorbed by the dorsolumbar column area. When the applied stresses exceed the yield strength of the bone tissue, fractures can occur in the vertebrae. Vertebral fractures constitute one of the leading causes of trauma-related hospitalizations, accounting for 15% of all admissions. Posterior pedicle screw fixation has become a common method for treating burst fractures. However, physicians remain divided on the number of fixed segments that are needed to improve clinical outcomes. The present work aims to understand the biomechanical impact of different fixation methods, improving surgical treatments.

A finite element model of the dorsolumbar spine (T11–L3) section, including cartilages, discs and ligaments, was created. The dorsolumbar stability was tested by comparing two different surgical orthopedic treatments for a fractured first lumbar vertebra on the L1 vertebra: the posterior short segment fixation with intermediate screws (PSS) and the posterior long segment fixation (PL). Distinct loads were applied to represent daily activities.

Results show that both procedures provide acceptable segment fixation, with the PL offering less freedom of movement, making it more stable than the PSS. The PL approach can be the best choice for an unstable fracture as it leads to a stiffer spine segment.

This study introduces a novel computational model designed for the biomechanical analysis of dorsolumbar injuries, aiming to identify the optimal treatment approaches within both clinical and surgical contexts.

Develop biodegradable meshes as a novel solution to address issues associated with using synthetic meshes for POP repair.

Computational models were created with variations in the pore geometry, pore size, filament thickness, and inclusion of filaments around specific mesh regions. Subsequently, one of the meshes was 3D printed to validate the results obtained from the simulations. Following this, a uniaxial tensile test was carried out on the vaginal tissue of a sow to compare with the simulations, to identify meshes that displayed behaviour akin to vaginal tissue. Finally, the most promising outcomes were compared with those of the uterosacral ligament and a commercially available mesh.

Following a comprehensive analysis of the results, the mesh that most accurately replicates the behaviour of the vaginal tissue showcases a smaller pore diameter (1.50 mm), filaments in specific areas of the mesh, and variable filament thickness across the mesh. Nevertheless, upon comparing the outcomes with those of the uterosacral, the meshes do not exhibit similar behaviour to the ligament. Finally, the commercially available mesh does not represent the behaviour of both the vaginal tissue and the uterosacral ligament and in this sense may not be the best treatment option for POP repair.

Their biocompatibility and biomechanical properties make them a potential solution to the disadvantages of synthetic meshes. Personalized/customized meshes could be part of the future of surgical POP repair.