Light-weight Self-Compacting Concrete (LWSCC) might be the answer to the increasing construction requirements of slenderer and more heavily reinforced structural elements. However there are limited studies to prove its ability in real construction projects. In conjunction with the traditional methods, artificial intelligent based modeling methods have been applied to simulate the non-linear and complex behavior of concrete in the recent years. Twenty one laboratory experimental investigations on the mechanical properties of LWSCC; published in recent 12 years have been analyzed in this study. The collected information is used to investigate the relationship between compressive strength, elasticity modulus and splitting tensile strength in LWSCC. Analytically proposed model in ANFIS is verified by multi factor linear regression analysis. Comparing the estimated results, ANFIS analysis gives more compatible results and is preferred to estimate the properties of LWSCC.

The constant growth of foundry modernization, mechanization and automation is followed with growing requirements for the quality and parameters of both moulding and core sands. Due to this changes it is necessary to widen the requirements for the parameters used for their quality evaluation by widening the testing of the moulding and core sands with the measurement of their resistance to mechanical deformation (further called elasticity). Following article covers measurements of this parameter in chosen moulding and core sands with different types of binders. It focuses on the differences in elasticity, bending strength and type of bond destruction (adhesive/cohesive) between different mixtures, and its connection to the applied bonding agent. Moulding and cores sands on which the most focus is placed on are primarily the self-hardening moulding sands with organic and inorganic binders, belonging to the group of universal applications (used as both moulding and core sands) and mixtures used in cold-box technology.

This paper focuses on mechanical properties of self hardening moulding sands with furfuryl and alkyd binders. Elasticity as a new

parameter of moulding sands is investigated. With the use of presented testing equipment, it is possible to determine force kinetics and

deformation of moulding sand in real time. The need for this kind of study comes from the modern casting industry. New foundries can be

characterized with high intensity of production which is correlated with high level of mechanization and automatization of foundry

processes. The increasingly common use of manipulators in production of moulds and cores can lead to generation of new types of flaws,

caused by breakage in moulds and cores which could occur during mould assembly. Hence it is required that moulds and cores have high

resistance to those kinds of factors, attributing it with the phenomenon of elasticity. The article describes the theoretical basis of this

property, presents methods of measuring and continues earlier research.

The paper presents the modelling measurement results of the load-displacement relation for scaffold stands and bracings. In the case of stands, there are two sections of curves, i.e. a straight-line and curvilinear section, and in the case of bracings, two straight line sections as well as one curvilinear section are distinguished. As a result of analyses, it is concluded that the sections which can be approximated by means of linear functions should be distinguished in graphs, if possible. On the one hand, this results from the evaluation methods of scaffold components. Nevertheless, the determination of elastic-linear scope of components’ operation is useful in engineering practice during computer calculations. Moreover, the method of determining an intersection point between functions, approximating tests results, along with analysis of the impact of polynomial degree, approximating the research results, on the time and effectiveness of the process of approximating functions selection, are all demonstrated in this article. The proposed method can prove useful in all science fields where curves obtained from any research (laboratory test, in situ test, numerical analysis) require approximation or replacement with a simpler description.

This paper investigates the influence of surface effects on free transverse vibration of piezoelectric nanowires (NWs). The dynamic model of the NW is tackled using nonlocal Timoshenko beam theory. By implementing this theory with consideration of both non-local effect and surface effect under simply support boundary condition, the natural frequencies of the NW are calculated. Also, a closed form solution is obtained in order to calculate fundamental buckling voltage. Finally, the effect of small scale effect on residual surface tension and critical electric potential is explored. The results can help to design piezo-NW based instruments.

The progressive development of miniature systems increases the demand for miniature parts. Reducing the size of manufactured components on one hand is a serious challenge for traditional technologies, but on the other hand, mainly by removing the energy barrier opens the possibility of using other unconventional techniques. A good example is the ultrasonic excitation of the punch during the micro-upsetting process. The anti-barreling phenomenon and dependent on the amplitude of vibrations, intensive deformation of the surface layers in contact with the tools at both ends of the sample was noted. Based on the measured strains and stresses, an increase in temperature in the extreme layers to approx. 200°C was suggested. By adopting a simplified dynamic model of the test stand, the possibility of detaching the surface of the punch from the surface of the sample was demonstrated.

The paper is dedicated to the discussion of elastic coefficients of wood. Parameters for wood presented in the literature are critically evaluated and discussed. The orthotropic mathematical model, with nine different elastic parameters, is one of the most often used models of wood. However, mathematical limitations on these parameters for the correct model are not well known. Based on these limitations, the verification of orthotropic elastic parameters for different species of wood is presented. The analysis shows that the published data are often unclear and sometimes wrong. The attempt to relate experimental results to the mean values specified in the standards is the second aspect considered in this paper. The designer, a user of these standards, should have clear information that the given parameters are specified for specific mathematical model and species of wood. This paper attempts to propose such a classification.

A crucial feature in health monitoring of already existing structures is to be seen particularly in identifying their topical internal structural parameters and controlling their remaining bearing capacity in the course of ageing processes. This is commonly carried out by measuring the deformations/strains caused by test-loading and calculating the parameters on the basis of the metered data.

In the case of elastic response of materials, the information on the parameters is directly related to the time of measurement; in the case of visco-elastic response, however, the history of the time-depending structural response during the period between initial loading and initiating the test-measurements is generally unknown. The problem exists, then, to separate the superimposed strains due to the existing state and to the test-load. For solving the problem, at first the relevant relations between stress/strain and the visco-elastic parameters are considered. Then a procedure will be described how to determine the strain state owing to the test-load only and to calculate the relevant parameters as functions of time. According to the principle of time-shift invariance, the results describe the time-depending response of the viscoelastic material, no matter at which time the loads are applied.

The presented method will be illustrated by two simple but instructive examples.

Concrete is the most widely used construction material because of its specialty of being cast into any desired shape. The main requirements of earthquake resistant structures are good ductility and energy absorption capacity. Fiber reinforced concrete possesses high flexural and tensile strength, improved ductility, and high energy absorption over the conventional concrete in sustaining dynamic loads. The aim of this paper is to compare the properties of concrete beams in which three types of fibers are added individually. Steel fibers, polypropylene fibers and hybrid fibers were added to concrete in the weight ratio of four percentages in the preparation of four beam specimens. The fourth specimen did not contain fibers and acted as a control specimen. The dimensions of the beam specimens were 150 × 150 × 700 mm. The reinforced concrete beams of M30 grade concrete were prepared for casting and testing. Various parameters such as load carrying capacity, stiffness degradation, ductility characteristics and energy absorption capacity of FRC beams were compared with that of RC beams. The companion specimens were cast and tested to study strength properties and then the results were compared. All the beams were tested under three point bending under Universal Testing Machine (UTM). The results were evaluated with respect to modulus of elasticity, first crack load, ultimate load, and ultimate deflection. The test result shows that use of hybrid fiber improves the flexural performance of the reinforced concrete beams. The flexural behavior and stiffness of the tested beams were calculated, and compared with respect to their load carrying capacities. Comparison was also made with theoretical calculations in order to determine the load-deflection curves of the tested beams. Results of the experimental programme were compared with theoretical predictions. Based on the results of the experimental programme, it can be concluded that the addition of steel, polypropylene and hybrid fibers by 4% by weight of cement (but 2.14% by volume of cement) had the best effect on the stiffness and energy absorption capacity of the beams.

The half-metallic, mechanical, and transport properties of the quaternary Heusler compound of PdZrTiAl is discussed under hydrostatic pressures in the range of –11.4 GPa to 18.4 GPa in the framework of the density functional theory (DFT) and Boltzmann quasi-classical theory using the generalization gradient approximation (GGA). By applying the stress, the band gap in the minor spin increases so that the lowest band is obtained 0.25 eV at the pressure of –11.4 GPa while the maximum gap is calculated 0.9 eV at the pressure of 18.4 GPa. In all positive and negative pressures, the PdZrTiAl composition exhibits a half-metallic behavior 100% spin polarization at the Fermi level. It is also found that applying stress increases the Seebeck coefficient in both spin directions. In the minority spin, the n-type PdZrTiAl, the power factor (PF) for all the cases is greater in the equilibrium state than the strain and stress conditions whereas in the majority spin, the PF value of the stress state is greater than the other two. The non-dimensional figure of merit (ZT) is significant and is about one in spin down in the room temperature for the all pressure states that it remains on this value by applying pressure. The obtained elastic constants indicate that the PdZrTiAl crystalline structure has a mechanical stability. Based on the Yong (E), Bulk (B) and shear (G) modulus and Poisson (n) ratio, the brittle-ductile behavior of this compound has been investigated under pressure. The results indicate that PdZrTiAl has a ductile nature and it is a stiffness compound in which elastic and mechanical instability increases by applying strain.

A spectrum defragmentation problem in elastic optical networks was considered under the assumption that all connections can be realized in switching nodes. But this assumption is true only when the switching fabric has appropriate combinatorial properties. In this paper, we consider a defragmentation problem in one architecture of wavelength-spacewavelength switching fabrics. First, we discuss the requirements for this switching fabric, below which defragmentation does not always end with success. Then, we propose defragmentation algorithms and evaluate them by simulation. The results show that proposed algorithms can increase the number of connections realized in the switching fabric and reduce the loss probability.

The aim of this study was to determine the hardness and reduced modulus of elasticity of juvenile wood of Scots pine (Pinus sylvestris L.) using the nanoindentation method, and then to compare the results obtained with those of mature wood. The hardness of juvenile pine wood determined by means of the nanoindentation method was 0.444 GPa while for mature wood it was 0.474 GPa. Statistically significant differences between the values were found. The reduced modulus of elasticity in juvenile wood was 14.0 GPa and 16.4 GPa in mature wood. Thus, the hardness values obtained were about 7% higher, while the modulus of elasticity was 17% higher in mature wood. All determinations were made in the S2-layer of the secondary cell wall.

Development of contemporary building industry and related search for new aesthetical and functional solutions of monumental buildings in the centers of large cities resulted in the interest in glass as a structural material. Attractiveness of glass as a building material may be derived from the fact, that it combines transparency and aesthetical look with other functional features. Application of glass results in modern look of building facades, improves the indoor comfort without limiting the availability of natural daylight. Wide implementation of the new high performance float flat glass manufacturing technology, in conjunction with increasing expectations of the construction industry relating to new glass functions, has led to significant developments in glass structures theory, cf. [1, 3, 4, 5, 9, 10]. Many years of scientific research conducted in European Union countries have been crowned with a report CEN/TC 250 N 1050 [2], compiled as a part of the work of European Committee for Standardization on the second edition of Eurocodes - an extension of the first edition by, among others, the recommendations for the above mentioned design of glass structures, in particular modern procedures for the design of glass building structures. The procedures proposed in the pre-code [2] are not widely known in Poland, and their implementation in the design codes should be verified at the country level. This task is undertaken in this paper.