Magnetic properties of Fe nanowire arrays (NWs) electrodeposited in anodic alumina membranes have been studied. The influence of nanowire geometry (length, pore diameter) and an external magnetic field applied during electrodeposition process on the magnetic properties of nanowire arrays was investigated. With the use of the X-ray diffraction analysis the structure of iron wires was determined. The iron wires have the regular Body Centered Cubic structure. Magnetic measurements show that shape anisotropy aligns the preferential magnetization axis along the wire axis. It was found that the application of an external magnetic field in a parallel direction to the sample surface induces magnetic anisotropy with an easy axis of magnetization following the nanowire axis. The dependence of the height of Fe wires on the electrodeposition time was determined.

The Goss texture is a characteristic feature of grain-oriented transformer steel sheets. Generator sheets, which are produced as non-oriented steel sheets, should have isotropic features. However, measurement results of generator sheets, confirmed by crystallographic studies, indicate that these sheets are characterized by certain, quite significant anisotropy. The first purpose of this paper is to present the influence of textures of generator and transformer steel sheets on their magnetization characteristics. The second aim is to propose a method which takes into account the sheet textures in the calculations of magnetization curves. In calculations of magnetization processes in electrical steel sheets, models in which the plane of a sheet sample is divided into an assumed number of specified directions are used. To each direction a certain hysteresis loop, the so-called direction hysteresis, is assigned. The parameters of these direction hystereses depend, among other things, on the texture type in these steel sheets. This paper discusses the method which calculates the parameters of these direction hystereses taking into account the given sheet texture. The proposed method gives a possibility of determining the magnetization characteristics for any direction of the field intensity changes.

Reinforced concrete composite slab consists of a thin prefabricated slab in which span reinforcement is located and of concrete joined with the slab, with such concrete being laid on site.

The existence of a joint of two concretes in such floors is interpreted as introducing a contact layer into a monolithic slab. In the paper parameters of two models are estimated. The first is a model of a contact layer and the second is a model of a composite slab with a single degree of freedom. The models consider that the contact has elastic properties and inelastic properties causing energy dissipation. Experimental investigations are discussed further based on which the parameters values of the contact layer model were determined.

Delamination was experienced for the slabs characterised by low contact layer stiffness after applying a maximum load. In addition, the strains of a contact layer having low stiffness are accompanied by lower energy dissipation than of a layer with high stiffness.

The smaller stiffness of composite floors, as compared to monolithic floors, occurs as a consequence of the existence of a joint. Such decrease for a composite slab is interpreted in the model with a single degree of freedom as the serial connection of stiffness of a monolithic slab and an element considering the existence of a contact layer.

The stiffness of an element considering the existence of a contact layer decreases along with a load, and the elements corresponding to the higher stiffness of the contact layer are characterised by higher energy dissipation.

The aforementioned results of the investigations confirm the assumptions of the contact layer model and a composite slab model with a single degree of freedom. The findings made represent a basis for establishing a method of evaluating the condition of a joint in composite slabs according to statistical investigations.

The ways of the improvement of the method for the determination of steel losses in the electrical devices of basic types are substantiated. The method is refined by taking into account the magnetic system properties at high saturation. The presence of the interrelation between the special features of the domain structure movement and the shape of the hysteresis loop is proved for laminated cores. It enabled the explanation of the causes for the abnormally high values of the losses in the steel and the atypical shapes of the hysteresis loops at its high saturation. The empiric dependence for the determination of steel losses is obtained. It provides for the high convergence of the calculated and experimental data at the actual degree of saturation and can be used in the direct-current operation of the analyzed devices.

This study describes a method that allows the modelling of magnetisation processes in transformer steel sheets for any direction of the magnetic field strength. In the proposed approach, limiting hysteresis loops for the rolling and transverse directions were used. These loops are modified depending on the magnetisation angle between the direction of the field strength vector and rolling direction. For this purpose, unique correction coefficients, which are functions of the magnetisation angle, were applied for both hysteresis loops. An algorithm for determining the limiting hysteresis loops for any magnetisation angle is presented herein. The calculation results for several cases of magnetisation were compared with the measured hysteresis loops.

This paper concerns the problem of empirical investigation and mathematical modelling of a novel controllable damper using vacuum packed particles. Vacuum packed particles tend to be placed among the group of so-called ‘smart structures’. The macroscopic mechanical features of such structures can be controlled by the partial vacuum parameter. The authors consider an application of Bouc-Wen model in order to represent the dynamic behaviour of the investigated device. The verification of the model response with experimental data is discussed. The Bouc-Wen model parameters identification is described.

The control of structural vibrations due to ground motion can be done by the installation of a passive, active, and hybrid base isolation system. The primary function of the base isolator is to support the superstructure and provide huge horizontal flexibility and a long period of vibration. In this paper, a special HRDB base isolator is made from natural rubber with special elastic property and hardness. This base isolator is designed to support gravity loads of two-story RC building. The experimental hysteresis loop of this isolator is validated with analytical modeling hysteresis loop using Hysteresis program. The Bouc hysteresis rule was chosen as a model the hysteresis loop, and it is similar to experimental hysteresis loops. Later, a single bay two-story RC frame with a base isolation system was modeled using Ruaumoko 2D program subjected to three levels of earthquake excitations. After analyzing this frame under the 1994 Pacoima Dam Earthquake, the 1995 Kobe Earthquake and the 1940 El-Centro 1940 Earthquake. The numerical results show that this isolator is quite efficient in reducing the damage of structural and non-structural elements of the structure through minimizing inter-story drift, lateral displacement, and story acceleration. Therefore, this special HRDB based isolator is recommended to be used for low rise and medium-rise building in seismic regions.