Vibrations of fixed-fixed heterogeneous curved beams loaded by a central force at the crown point

This paper addresses the vibrations of heterogeneous curved beams under the assumption that the load of the beam is a dead one and is perpendicular to the centroidal axis. It is assumed that: (a) the radius of curvature is constant, and (b) Young’s modulus and the Poisson’s number depend on the cross-sectional coordinates. As for the issue of fixed-fixed beams, the objectives are the following: (1) to determine the Green’s function matrices provided that the beam is under radial load; (2) to examine how the load affects the natural frequencies given that the beam is subjected to a vertical force at the crown point; (3) to develop a numerical model which makes it possible to determine how the natural frequencies are related to the load. The computational results are presented graphically

NEW APPROACH TO ESTABLISHING POISSON’S RATIOS OF SOFT-WOOD COMPONENTS

In literature, one can usually find experimental investigations into global mechanical behaviour of soft-wood specimens, but properties of their individual components, (namely the properties of the late-wood and the early-wood parts) are rarely presented. Therefore, information on the moisture content and on the density is presented here. In fact, the ratio of the early- and late-wood parts in the cross-sectional area represents a significant influential factor, especially in the case of soft-wood components. Based on previous experimental data bases, the authors offer an original and simple analytical method for establishing Poisson’s ratios for new, untested soft-wood specimens

Thermal Scaling of Transient Heat Transfer in a Round Cladded Rod with Modern Dimensional Analysis

Heat transfer analysis can be studied efficiently with the help of so-called modern dimensional analysis (MDA), which offers a uniform and easy approach, without requiring in-depth knowledge of the phenomenon by only taking into account variables that may have some influence. After a brief presentation of the advantages of this method (MDA), the authors applied it to the study of heat transfer in straight bars of solid circular section, protected but not thermally protected with layers of intumescent paints. Two cases (two sets of independent variables) were considered, which could be easily tracked by experimental measurements. The main advantages of the model law obtained are presented, being characterized by flexibility, accuracy, and simplicity. Additionally, this law and the MDA approach allow us to obtain much more advantageous models from an experimental point of view, with the geometric analogy of the model with the prototype not being a necessary condition. To the best knowledge of the present authors there are no studies reporting the application of the MDA method as it was used in this paper to heat transfer