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The types of slit walls energy dissipators, from monolith or precast reinforced concrete, proposed by researchers and the seismic behaviour of these types of walls are described. The overall ductility of the structure increases, considering the energy dissipation solutions proposed by the researchers of the reinforced concrete walls, resulting a supplementary safety for the structure. The objective of these solutions is to create an ideal structure for tall multi-storey buildings, that behaves as a rigid structure at low seismic action and turns into a flexible one in case of a high intensity earthquake action. The solutions for increasing ductility proposed in this paper are viable and easily to use in constructions practice. For the analysis of slit wall, the researchers used a series of analytical calculation methods, among the most important being the equivalent frame method and the finite element method, both presented s. 3 of the paper. The researchers concluded that by using this calculations methods, the dynamic behaviour of the reinforced concrete slit walls can be simulated very accurate and realistic.

In order to verify and perfect the theory of hinge-joined plate method and make it serve the bridge design better, this paper was written based on an actual bridge, and the ANSYS finite element model was established. Compared the hinge-joined plate method results with the analysis results and through the investigation and data analysis, it could be found that the assumption that the hinge-joined plate theory for the board lateral force transmission is reasonable, but the assuming hinge joints that only withstand shear stress and just have the shear checking is unreasonable. At the same time, this paper also proved that the strength reduction getting from the old and new concrete interface should be taken into account when using the hinge-joined plate method to calculate the transverse distribution coefficient and the effects on overall stiffness that the joint depth and thickness of deck pavement to the beam bridge.

This study investigates the effectiveness of using Hairpin shaped stirrups to increase the shear capacity of beams and slabs. The hairpin system consists of inverted U-shape stirrups welded to flexural corner rebar. Previous research works proved the increase of the hairpin system in increasing the two-way shear capacity compared to conventional punching reinforcement. However, the system’s ability to increase the shear capacity of beams has not been explored. This paper presents the results of Finite Element simulation of two beams performed using ABAQUS Software; one beam is reinforced with conventional shear stirrups, and the other is reinforced with hairpin stirrups. The load capacity, deflection and damage pattern of the two beams were compared. Results showed that beams reinforced with hairpin stirrups have higher load capacity and ductility compared to beams with conventional stirrups. However, the reinforcement type had little effect on the shear damage pattern.

Mathematical and numerical models of Fe-C alloy solidification process based on the finite element method (FEM) are presented in the paper. The phenomenon of the defect called "shrinkage cavity" is introduced to the model. It is very important aspect of presented work which makes possible the prediction of the location and shape of mentioned defect depending on the geometry of the casting and cooling condition of the process. An original computer program using Visual C++ environment has been written in order to simulate described process. The results of computer calculations of the three-dimensional solidification problem of the casting with riser are presented and discussed in details.

This paper presents a modification of the existing optimalization model in order to increase the accuracy of the solution in the initial and the end part of the bend. Developed optimalization algorithms are implemented in the program MATLAB, and the simulation of the bending process is solved in the FEM program ADINA. Created optimisation program automatically generate model for FEM analysis and automaticaly analyses obtained results from FEM analysis.

The numerical approach based on the finite element method (FEM) for modeling of mechanical interaction between three-dimensional objects is presented in the paper. The model of contact is based on the assumption that the nodes of the region which is the source of contact cannot overlap with the nodes of the region being the target. The procedure of the detection of collision between surfaces of the source and the target is discussed in details. The behaviour of surfaces being in contact depends on their rigidity and is numerically modeled in the case of perfectly rigid source and deformable target. Each modeled object has an independent mesh of finite elements. These meshes can be freely moved relative to each other. Example of calculation using original program written in C++ is presented and discussed.

This paper presents a kinematic and dynamic analysis and distribution of the stress for six-item planar mechanism by means of the SolidWorks software. Graphic dependence of kinematic and dynamic magnitudes of some points is given in dependence on the angle of rotation of the driving item and in dependence on the time. Distribution of the stress in the items is presented in [Pa]. In relation to the kinematic and dynamic analysis and subsequent simulation of the planar as well as spatial mechanisms, it is great solution to use SolidWorks software program. The considerable advantage of this mentioned program is based on its simplicity from the aspect of modeling and moreover, it is important to point out that utilisation of the mentioned program leads to results which are precise and accurate in the case of the numerical solution of the equations in the whole magnitude referring to motion of mechanism while the given results are obtained in the graphic form.

The paper presents the problem of static analysis of sandwich structures with a non-continuous soft core. In the numerical 3D FE models, the core is divided into separated parts. The contact between these parts has the form of unilateral constraints. The model also allows for local debonding of the facing and local imperfections of sandwich panel geometry. Particular attention is paid to the problem of local instability of the facing that is compressed during bending. The phenomenon of progressive damage and the influence of non-continuity of the core on the structural behavior of the sandwich panel is also discussed.

The paper presents a numerical model of 2-D microstructure of rigid polyurethane foam. The selection of geometric and material parameters is presented. For a particular structure, its behavior has been studied for typical cases of external loads (or forced displacements). The characteristic phenomena have been identified and described. A parametric analysis was performed due to the dimension of the cross-section of the struts which form the cell edges. An analysis of the impact of support and loading conditions on the behavior of the cell structure was performed.

Many structural elements in technical devices, as well as some tools in manufacturing equipment, such as saw blade or, have a geometric shape similar to a circular disc. In many cases, these circular discs must meet the required dynamic properties. One of the techniques to achieve the required dynamic properties of circular disc is based on initiating pre-stressed fields in the disc plane. In-plane residual stresses are created by appropriate technological treatments in selected disc part, for example by rolling of annulus leading to plastic deformation which causes the change of volume distribution in this disc part. The effects of in-plane residual stresses on modal properties of circular disc are analysed. The natural frequencies modifications depending on position and width and also on the change in thickness of the roll-prestressed annulus are investigated in this paper.

The paper is devoted to the problems related to buckling analysis of graphene sheets without and with vacancies in the structure under different boundary conditions. The analysis was performed by the classical numerical treatment – the finite element method (FEM). The graphene sheets were modelled by beam elements. Interatomic relations between carbon atoms in the structure were represented by the beams connecting individual atoms. The behaviour of the beam as structural element was based on the properties that were established from relations of molecular mechanics. The vacancies in single layer graphene sheets (SLGSs) were created by elimination of randomly chosen atoms and corresponding beam elements connected to the atoms in question. The computations were accomplished for different percentage of atom vacancies and the results represent an obvious fact that the critical buckling force decreases for increased percentage of vacancies in the structure. The numerical results are represented in form of graphs.

The method of numerical modeling of heat transfer between three-dimensional objects being in contact is described in the paper. Presented approach is based on the finite element method (FEM) with independent spatial discretization of considered regions. The gap between external surfaces of the interacting objects has variable width and is filled with gas or liquid. The medium in the gap introduces thermal resistance into heat transfer process. The mathematical model of considered problem is based on the equation of heat diffusion supplemented by the appropriate initial and boundary conditions. The deformations of the regions resulting from the thermally dependent changes of their volumes are also included in the model. The results of numerical simulations are presented and discussed.

This paper presents a kinematic and dynamic analysis and distribution of the stress for four-item planar mechanism by means of the SolidWorks software. Graphic dependence of kinematic and dynamic magnitudes of some points is given in dependence on the angle of rotation of the driving item and in dependence on the time. Distribution of the stress in the items is presented in [Pa]. In relation to the kinematic and dynamic analysis and subsequent simulation of the planar as well as spatial mechanisms, it is great solution to use SolidWorks software program. The considerable advantage of this mentioned program is based on its simplicity from the aspect of modeling and moreover, it is important to point out that utilisation of the mentioned program leads to results which are precise and accurate in the case of the numerical solution of the equations in the whole magnitude referring to motion of mechanism while the given results are obtained in the graphic form.