Honeycomb sandwich (HS) structure has been widely used in aerospace applications because of its high specific strength and high specific stiffness. The structure of the lightweight HS panel is complex. Thus, establishing an equivalent simplified model is indispensable to improve the efficiency of the dynamic analysis of HS panels. In this paper, three commonly used dynamically equivalent modeling methods for HS panel are studied.

In the field of oil & gas drilling engineering, the Rotary Steerable System (RSS) is very widely used in directional drilling, the whole drillstring is rotated from the surface by a hydraulically driven top drive. In this paper we analysis of the dynamic model of the Rotary Steerable System (RSS) with a single stabilizer and flex-sub and takes a method of the longitudinal and transverse bending continuous beam method to analyse the stress of RSS with the flex-sub.

This paper presents a way to model the rotational constraint between beam elements in 3-D space. Beam elements are models used to simulate the behavior of slender objects. Such objects can be found for e.g. in bridges, space structures, robots, and networks of fibers (paper, cloth, biological tissue, etc). In many cases, beam elements are welded or bonded together. To model this bonding, the relative displacements and rotations shall be limited at the contact point using appropriate constraints.

The paper is concerned to the computation of eigenfrequencies of single-walled carbon nanotubes (SWCNTs). Classical treatment, where the nanotube is approximated by beam theory, is replaced by the nonlocal theory of beam bending. The eigenfrequencies are computed by combination of analytical, as well as numerical methods for four types of boundary conditions. The results can be used for determination of Young’s modulus of homogenized SWCNTs from experimental measurements.

In this paper, a numerical model for the analysis of bond-slip occurring in concrete filled steel tube (CFT) columns is introduced. The introduced model considers the bond-slip effect by incorporation of the equivalent steel stiffness. Finally, the validity of the introduced numerical model is verified by comparing the experimental data with the analytical results for CFT columns subjected to axial force and bending moment.