Use of TMD in structural engineering: Building Parque Araucano in Santiago de Chile

Congreso celebrado en la Escuela de Arquitectura de la Universidad de Sevilla desde el 24 hasta el 26 de junio de 2015.The application of Tuned Mass Dampers in mechanical engineering is of longstanding and habitual use. In these kinds of applications, the loading forces are based on constant frequencies and they are in most case well known. The application of a TMD in structural engineering is more recent, beginning a few years ago under the concept of seismic protection. The design of a TMD for a building presents the practical difficulty of tuning the device to the fundamental period of the structure. Through the application of additional damping, it is possible to widen the range of tuning frequencies and therefore increase the effectiveness of the TMD. Additionally, the seismic loads to which the structure will be submitted are uncertain in their frequency distribution which could generate a counterproductive effect, because the response of the building to the seismic forces could be even worse with the use of TMD. The addition of more damping has the result of a reduction of the positive effect of the TMD at the fundamental frequency, but produces a better response for the entire range of frequencies of the seismic excitation. The following work shows both the theoretical and practical application of this concept to a building built in 2006 in Santiago de Chile, which passed unscathed the 2010 Maule Earthquake, which reached a magnitude 8,8 Mw with an intensity VIII in the locations of the building

Analysis of Electrical Coupling Parameters in Superconducting Cables

The analysis of current distribution and redistribution in superconducting cables requires the knowledge of the electric coupling among strands, and in particular the interstrand resistance and inductance values. In practice both parameters can have wide variations in cables commonly used such as Rutherford cables for accelerators or Cable-in-Conduits for fusion and SMES magnets. In this paper we describe a model of a multi-stage twisted cable with arbitrary geometry that can be used to study the range of interstrand resistances and inductances that is associated with variations of geometry. These variations can be due to cabling or compaction effects. To describe the variations from the nominal geometry we have adopted a cable model that resembles to the physical process of cabling and compaction. The inductance calculation part of the model is validated by comparison to semi-analytical results, showing excellent accuracy and execution speed

A continuum model for current distribution in Rutherford cables

An analysis of eddy currents induced in flat Rutherford-type cables by external time dependent magnetic fields has been performed. The induced currents generate in turn a secondary magnetic field which has a longitudinal periodicity (periodic pattern). The dependence of the amplitude of the pattern on the history of the cable excitation has been investigated. The study has been carried out with two different models for the simulation of current distribution in Rutherford cables, namely a network model, based on a lumped parameters circuit and a "continuum" model, based on a distributed parameters circuit. We show the results of simulations of the current distribution in the inner cable of a short LHC dipole model in different powering conditions and compare them to experimental data. (12 refs)

An Update of Eyeglasses-Supported Nasal–Facial Prosthetic Rehabilitation of Cancer Patients with Post-Surgical Complications: A Case Report

Featured Application: This case report aims to describe an update of the digital protocol for the fabrication of a facial prosthesis for those patients who cannot be rehabilitated with plastic surgery because of post-surgical complications after maxillofacial surgery. In detail, it describes the application of the digital protocol to a mid-facial defect. The innovation proposed is oriented to simplify the procedures and reduce the time and cost of the process, aiming to recover the quality of life of inoperable patients. This case report aims to describe novel steps in the digital design/manufacturing of facial prostheses for cancer patients with wide inoperable residual defects, with a focus on a case of a mid-facial defect. A facial scanner was used to make an impression of the post-surgical residual defect and to digitalize it. The daughter’s face scan was used for reconstructing the missing anatomy. Using 3D printing technologies, try-in prototypes were produced in silicone material. The substructure was laser melted. The final prosthesis was relined directly onto the patient’s defect. The prosthesis resulted in a very low weight and a high elasticity of the external margins. The laser-melted substructure ensured the necessary rigidity with minimum thickness