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In the last years, the use of floating concrete caissons in coastal infrastructures has been generalized: docking structures, vertical breakwater and special floating structures. In this field, one of the most important and less analyzed stages of the marine works is the sinking process of the floating caissons. The test campaign presented in this work is innovative in scale (1:12) and includes an analysis of the different stages of a floating caisson during its life cycle: detached concrete caisson, caisson positioning and sinking and berthed floating caisson, resulting in more than 130 tests performed. Movements and tensions have been analyzed for a wide array of sea states and different configurations of mooring systems and horizontal layouts. A new tool for dynamic positioning control was designed and developed as part of the test campaign. The design of this tool has led to the development of a specific numerical model that reproduced the dynamic behavior during sinking. The dynamic positioning control was implemented in the physical model campaign, which has meant an important advance in the construction process of maritime infrastructures. Moreover, the campaign carried out has allowed the validation and calibration of the tools developed, allowing all the work to reduce costs and increase the safety of these types of marine operations.

Whereas bone mineral density (BMD) is characteristically low in osteoporosis, it has been postulated that in osteoarthritis BMD is increased. We aimed to check this concept by analyzing bone volumen and structure in the femoral heads of patients with hip fractures (n=10) and with hip osteoarthritis (n=9). Unexpectedly, the analysis of microstructural parameters by microCT did not reveal significant differences between both groups. In addition, we did not find a significant decline in the trabecular bone volume across the age range studied. These results suggest that the evolution of the trabecular bone of the femoral head is different from the age-related decrease of bone mass in other regions of the skeleton. Elucidating the mechanism involved could suggest new approaches to treat the bone loss associated with aging.

This work analyses the mooring and power cable dynamics in large-scale experimental tests carried out in the wave-current-tsunami flume (COCOTSU) facility at IHCantabria. The analysis is based on scaled elastic string models for a single chain-nylon mooring line and the dynamic cable of a 15MW floating offshore wind turbine (FOWT) supported by a concrete semi-submersible platform (ActiveFloat) in Gran Canaria Island (Spain). Both scaled concepts in the 100 m deep site are developed within the framework of the project COREWIND. All the test campaign is planned to be fully monitored; hence two overlapped video cameras register the line kinematics while the tensions are recorded in its two extreme points. The most difficult characteristic to fix in an elastic material at laboratory scale is the combined reproduction of axial and bending stiffness. On the one hand, to replicate the real axial stiffness in a chain-nylon mooring line, the first problem lies in finding a material capable of doing it with an acceptable hysteresis. The second issue consists in knowing the axial stiffness of the selected elastic material for each imposed oscillation, as it depends on the loading velocity. On the other hand, the limiting mechanical characteristic of the lazy-wave cable is the bending stiffness. To make the bending stiffness tests, we have previously built our own three-point bending flexural tester. 25 materials have been characterised to identify the best one for testing. From this analysis a database of materials has been derived. For each of the configurations analysed, a set of 40 forced oscillation tests are planned to reproduce either mooring fairlead or power cable connector movements in surge. An initial tension-deformation test is followed by 28 combinations of harmonic excitations with two origins, two amplitudes and seven periods, and 11 irregular time series obtained from the resulting surge displacements of the platform when simulating in OpenFAST extreme and severe Design Load Cases 1.3, 1.6 and 6.1. Experimental data obtained are stored in an online repository to make it freely available to the wind energy sector. The ambitious reduced scale tests proposed provide enough cases to deliver a benchmarking database for numerical models calibration including forces at anchor and fairlead, as well as line shape.