Structural behavior of large-scale triangular and trapezoidal threaded steel tie rods in assembly using finite element analysis
Abstract Pre-stressed steel tie rods are used extensively as load carrying components in structures like suspension bridges, steering systems in automotive vehicles, wings and fuselage of aircrafts, spokes of Ferris wheels, etc. The governing variables for the bearing strength of a large-scale steel tie rod (of diameter usually larger than 60 mm) include the mechanical strength of the tie rod body, geometric configuration of the thread teeth and the number of turns of thread engagement. The optimal number of turns of threaded connections of large scale steel tie rods has been predicted by full scale rupture experiments and reported previously by the authors. This paper builds up further on that work and investigates the structural behavior of the two types of threaded connections of steel tie rods, viz. (i) the triangle threaded connection, and (ii) the trapezoidal threaded connection, using finite element analysis in ANSYS. The axial displacement, equivalent stress distribution, interfacial contact pressure and sliding distance on the engaged thread teeth under different axial loads are presented and analyzed. The numerical simulations verify and expound the results of full-scale tensile rupture experiments. The concordant comparison between experimental measurements and finite element analysis provides working guidelines and support for the design and fabrication of steel tie rods in practical operations.
Influence of Thread Root Radius on Maximum Local Stresses at Large Diameter Bolts under Axial Load- ing
In the thread root area of the threaded bolts submitted to axial loading occur local stresses, higher that nominal stresses calculated for the bolts. These local stresses can generate failure and can reduce the fatigue life of the parts. The paper is focused on the study of the influence of the thread root radius on the maximum local stresses. A large diameter trapezoidal bolt was subjected to a static analysis (axial loading) using finite element simulation.
La participacion de los stakeholders en las iniciativas de branding del hospital en las redes sociales: una propuesta de modelo para construir marcas colectivas
Introduction : All health organizations face many managerial and economic challenges such as the consolidation of private and international hospitals, the increasingly interest of society for health education issues or the development of telemedicine. In this framework, many organizations prioritize social media as the main corporate communication tool for building a reputed brand in a collective way along with stakeholders. Objectives : This paper aims to identify a communication model allowing hospitals to efficiently apply branding initiatives on social media in order to build a brand in a collective way with stakeholders. Methodology : We carried out a literature review about corporate communication, health communication, branding and social media; and, then, we proposed the PET Model for Branding Hospitals on Social Media. Results and Conclusion : We conclude that hospitals should create a multidisciplinar corporate communication department, implement management initiatives for allowing health professionals have more time for using social media and integrate health education and patient’s empowerment in every communication initiative.