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When processing in the manufacture for production of paperboard boxes, there arises amount of waste paper as material, which is subsequently sent for recycling. The paper passes through the first crushing device, which ensures small pieces so that they can be transported by pipeline to a pressing apparatus. Paper material in the molding machine is forced into the pits of suitable size due to the additional handling and transport. So both pipe as well as the molding machine may be so congested with material during the failure that the equipment requires unexpected additional cleaning. The sensor detects the level of waste material in pressing device, thereby avoiding congestion in a timely manner and prevents subsequent failure. The sensor uses the resonant frequency of the oscillating rod. The microprocessor controls and evaluates the response of the rod oscillations. Sensor performance was exposed to qualification tests when it shows ability to operate also in extreme conditions such as dirty and dusty surrounding with high humidity and temperature level. Sensor detects the vibration attenuation at the poles of the rod that is caused by touching different materials. Thus may indicate changing concentration level of a material and not just pieces of paper but for example, also sand or other suitable materials or height of fluid surface.

The isogeometric formulation seems to be advantageous especially when it comes to curved geometries such as curved beams and shells. In this paper, the NURBS isogeometric formulation of beam element is presented. The same basis functions are used for both geometry description and unknown approximations so there is no accuracy loss caused by a geometry approximation. The element is based on Timoshenko beam theory which enables the use of the element for both thick and thin beams, nevertheless in case of thin beams the shear-locking phenomena is observed. In the paper it is shown that the reduced integration is insufficient for locking removal and capability of Discrete Shear Gap (DSG) method to unlock the elements is examined. For clear demonstration of locking-removal techniques the implemented element is first tested for the case of straight beam, then the performance is demonstrated on the curved geometry.

The aging of hydraulic concrete structure is a highly complicated problem. To reasonably evaluate the aging situation of a long-term operating concrete sluice, the core samples are obtained by field sampling from the sluice piers and the mercury injection experiment is carried out in this paper. The main objectives of this experimental investigation are to analyze the pore structure characteristics of the different parts in core samples and discuss the concrete aging rule of hydraulic concrete structure. The experimental results show that the aging of the hydraulic concrete has a certain relationship with the evolution of the concrete pore structure. It is feasible to use the pore structure of concrete to express the concrete aging of the hydraulic structure. The research in this paper will provide a basis for further study on the aging mechanism of the hydraulic concrete structure.

In the paper there are presented experimental results concerning mechanical characteristics of friction-welded joints in comparison with electron beam welded joints, made by 20VNiMoCr120 heat-resistant steel, which are part of some elements working at high pressure and temperature. The paper represents a study which suggests non-conventional welding and heat-treatment procedures for water and steam-supply pipes, large cylindrical recipients with high values of wall thickness, boiler pipes, steam turbines which compose thermo-energetic installations, in order to prevent failure appearance. The actual level of development in all activity fields proves the fact that on top of the performance and modernism, technological products and processes must assure a high reliability. All the results and experimental researches are obtained by the first author in her PhD Thesis.

This paper reports the stress distribution inside the workpiece under ultrasonic vibration cutting (UVC) condition. Many researchers have reported the improvements of tool wear, burr generation and surface integrity by reduction of time-averaged cutting force under UVC condition. However general dynamometers have an insufficient frequency band to observe the ultrasonically varying processing phenomena induced by UVC. In this paper, stress distribution inside the workpiece was observed by combining the pulse laser as light source synchronized with ultrasonically vibrating cutting tool and the photoelastic method. The one shot of pulse laser with pulse width of 15nsec visualizes an instantaneous stress distribution. Sweeping the phase of emission against to ultrasonic oscillation, 360 frames for 35.7μs, one period of ultrasonic oscillation, are captured. Because UVC induced an intermittent cutting condition, the stress distribution changed periodically and disappeared when the tool leaved from the workpiece. The ideal chip-generating period is calculated by relative motion between tool and work. We found that the actual chip-generating period was extremely longer than ideal period.

The aim of the present paper is to establish the optimal parameter values of the cutting regime of a milling process. The paper presents a study regarding the influence of the cutting parameters on the surface roughness of the material and also on the vibration generated by their combinations, during a processing by milling. The studies are made on samples made from S355 JR steel with a metal milling machine FUS 25, which is used also for the experiments. The samples dimensions are 210x150x16mm. For the experiments there was used a cylindrical - frontal milling tool, with 32mm diameter and 10 tooth. Basic parameters of milling processing of materials we have considered in this paper are: feed rate [mm/min]; cutting speed RPM [rot/min]; depth of cut [mm]. For each of this parameters three levels were envisaged. For a 100% accurate experiment results at least 27 experiments must be done. Using an L9orthogonal array, the number of experiments is reduced to nine and the accurate of the method is around 99.96%. The optimal process parameters values are obtained using Taguchi method considering three situations. In the first case the goal is to get only a fine roughness for the sample. The second studied case is focused on finding a low level for the vibration generated during the milling process. The aim of the last study is to find a fine roughness and also a low level of vibration for the process. The analysis of variance (ANOVA) is applied, in all cases, in order to estimate the error variance and to rank the process parameters according to their importance.

The paper is focused on the use of advanced composite materials in the real application areas of buildings exposed to extreme environmental stress. The paper describe properties of composite rebar, especially with regards to long-term resistance to chemical and corrosion attack, minimization of heat transfer or resistance in construction with reduced concrete cover. The paper also presents behavior of composite rebar and concrete samples with composite reinforcement during loading and fire tests.

The paper is about a research focused on a development of thin slabs made from white UHPC. These slabs are reinforced by scattered PVA fibres and textile glass reinforcement in form of 2D net. The aim of the experiment is the development of tin slabs that can be used as facade or roof panels. The course of the experimental tests of these slabs and its correspondence with the numeric analysis made with ATHENA software is in the paper. Three slab specimens with size of 750 x 125 x 15 mm were tested in four-point bending. The white UHPC matrix was reinforced by the scattered PVA fibres and the 2D textile glass reinforcement with mesh 20 x 20 mm. The used 2D reinforcement was coated against alkali conditions, so called AR - Glass with 2400 TEX fineness. The reinforcement was placed and fixed near the lower surface of the slabs. The course of the tests was continually monitored by an automatic measuring unit where especially the acting force, the deformation in the middle of the span, the deformation in the supports and the progressive formation and development of cracks were detected. The numeric model was created in 3D surroundings of Gid 2011 program and then converted into ATENA software.

This paper refers to behaviour and capacity of axially loaded columns strengthened under load using welded steel plates. This method of strengthening is fast, simple and widely used but no universal and reliable analytical solution has been presented yet. In the paper, focus is put on flexural buckling. The approach using cross-section properties of strengthened member and the modified buckling reduction factor was used to calculate the ultimate resistance. In buckling theory, the resistance of column subjected to compression load is reached when the most stressed fibres start to yield. However, some researchers allow certain amount of yielding for base material of columns strengthened under load. In the paper, the new modified buckling reduction factor based on Eurocodes is derived. Two types of column strengthening under various preload magnitudes are investigated using finite element study in ANSYS code and transient analysis type. Birth and death of elements is used to simulate strengthening welded plates. The results are compared with analytical solutions.

This paper investigated the damage degree and damage mechanism of aluminum sandwich plate subjected to blast loading by using numerical simulation method. Finite elements models of aluminum foam sandwich plates were established. The distortion and damage pattern of the sandwich plate under different masses of detonator were got by using LS-DYNA to simulate the destructive effect of shock wave and detonation product against sandwich plate. The results showed that the maximal deflection and overloading of the sandwich plates were different because of the changing of mass of detonator. This paper could provide some reference for the designing of sandwich structures.

The paper addresses the issues of fire behavior of masonry walls made of traditional/historical component materials (bricks and mortar). There are reasons for coupling investigations on the residual mechanical properties to fire resistance data, aiming at a more complete knowledge of the behavior of a masonry member during and after fire exposure. The paper is part of a research that aims at investigating the relationship between fire and post-fire (i.e. residual) mechanical behavior of masonry walls, paying attention to scale-related problems and to the possible exploitation of numerical tools to establish simplified approaches. The goal is to establish relationships between fire resistance ratings under exposure and decay in mechanical properties after exposure; the parameter of wall thickness is especially investigated, by choosing four different values (i.e. 12, 25, 38 and 51 cm). This is performed by means of FEM analysis with DIANA 9.4.4 software, simulating a standard ISO 834 fire resistance test followed by a mechanical compressive failure test on each investigated type of wall. The approach, successfully tested against experimental data already available, features a preliminary transient heat flow analysis which gives a numerical prediction of fire resistance after violation of I (Insulation) criterion; then, a staggered heat flow - stress analysis repeats the heating of the wall up to insulation failure and calculates the thermal strain accounting for cracking; finally, a ‘cold’ structural analysis in compression is performed on the thermally-deformed model after cooling. The paper also addresses a way for the extended application of the research outcomes, relying on a simple approach based on the concept of equivalent fire severity.

The maximum values of normal and shear stresses are the basic parameters which influence directly the initiation and propagation of multiaxial fatigue cracks.Based on the above, the first part of the paper presents an analysis of principal stresses (normal and shear) in case of symmetrical tension-compression loadings with superimposed phase-shifted symmetrical torsion cycles. The influence of stress amplitude ratio and phase shift on the maximum (normal and shear) stresses and on the directions of the planes along which these act is analyzed and graphically represented using stress hodographs.The second part of the paper highlights the possibility of using the maximum value of the normal or shear stress as base parameter for durability studies under multiaxial fatigue, based on existing experimental data. The mentioned data is correlated with the results of an original experimental program carried out by the authors on 41Cr4 steel and conclusions are formulated with regard to the role of maximum shear stress in life-time calculation.

Applications of precast elements made of UHPC have been increasing in recent years. Also in the Czech Republic, UHPC can be found as a structural material in first applications in both, buildings and transport structural engineering. Structures made from this modern material required experimental programs verification of material properties and also for determination of behaviour of structural elements. In previous research of the bond of UHPC and various types of reinforcement was proven to be very good, which makes it possible to reduce radically anchorage lengths. This paper deals in more detail with determination of the bond of prestressing strands and UHPC, during the first week after casting, in particular. For prestressing of precast elements, there are very important short-time strengths and short-time bond is showing to be a decisive factor for optimum prestressing time. Second part of the paper is focused on impact of thermal stress on bond of prestressing strands and UHPC. Samples were subjected to the cycling heat/frost and effect of a number of cycles on final bond behaviour of both UHPC and ordinary concrete were investigated. The article describes differences between ordinary concrete and UHPC.

The bridge across the Hostovsky creek, on the expressway R1 on Slovakia was open to public traffic at autumn 2011. The bridge itself is measured since the time of erection. The authors of the presented paper are now preparing a new plate-element model, which shall contribute to the better prediction of the long-time behaviour. In this paper, the new model is presented and compared with the measurements from the static test of the bridge.

The paper deals with a system of precast floor plates from lightweight concrete intended mainly for building of family houses and residential construction. The developed system has two types of precast floor plates made from lightweight concrete: floor plates for floor systems and solid section floor plates. This paper describes solid section floor plates. The unambiguous advantage of lightweight concrete floor construction is weight lower by as much as 37% compared to floor structure made from common concrete, while bearing strength remains unchanged as well as high fire resistance. This type of floor slabs has also been successful in the system of assembled prefabricated houses thanks to its lower weight and elimination of the wet construction process.

Ionic Polymer Composite Material (IPMC) is a new type of smart material which has the capability of activation under the application of a small voltage. It is flexible; light weighed, produces high force and can be activated in any two opposite directions. These benefits have inspired the scientists and researchers to explore its availability for real-world applications in various fields. In this paper, the application of IPMC has been considered for the provision of required force to the movement of a grasshopper knee joint for the upward or stretching movement by the knee. In other words, it has been proposed to act as an artificial muscle for the mentioned job. Furthermore, simulation is carried out for two separate conditions of the weight ratios of the weight of the leg and that of the IPMC strip and simulation is carried out to clarify the relation between the force and deflection. The simulation is based on mathematical model that has been previously developed. Analysis of the simulation results of the two conditions indicated that more force is required to move a heavier leg by a certain amount of angle as compared to the force requirement for moving a lighter leg. This paper represents the simulation results for the upward movement of the link; however the same model and its simulation can be applied to that of the reverse direction because of the unanimity of the material properties and specifications.

The gear honing is the most economical way for hard finishing an involute helical gear after hobbing and heat treatment or after shaving and heat treatment. The gear honing can also be applied to the modification of gear tooth surfaces to compensate for the distortions that occur during heat treatment process. Most published papers on the technology of gear honing describes on the principle of generated gear surface. However, the longitudinal tooth flank crowning of a helical gear with honing has not been investigated yet. Therefore, in this paper, we proposed a novel method for longitudinal tooth flank crowning of work gear surfaces by setting a crossed angle between the honing cutter and work gear axes as a linear function of honing cutter's traverse feed in the honing process. A mathematical model for the tooth profile of work gear honed by a standard honing cutter is also established. Three numeral examples are presented to illustrate and verify the merits of the proposed gear honing method in longitudinal crowning.

In this paper, the dynamic tension of bullet-proof steels processed by hot stamping are tested on MTS810 and Hopkinson bar, in which four types of steels (B1, B2, C1 and C2) are used. For each sample, the flow behavior is predicted via Johnson-Cook (JC), Modified Johnson-Cook (MJC) and Cowper-Symonds (CS) models on the basis of experimental data, respectively, and the calculation method is also introduced. After that, the errors between prediction of each model and experimental data are analyzed and discussed. As a result, the most appropriate constitutive model for dynamic flow behaviors of bullet-proof steel is proposed. Moreover, our in-house software has been developed for calculating, comparing and selecting typical constitutive models for dynamic flow behaviors of materials, which has the functions of parameters input and output, curve plotting and data storing. The work carried out in this paper will be beneficial for accurate simulation of materials deformation.

With the current development of hot stamping technology, quality products have been striving for not only uniformity in hardness but also a minimum of springback. Considering the fact that the uniformity distribution of hardness and the randomness distribution of the springback are inevitable in hot stamping process due to many complex factors such as contact sequence, contact clearance, scale and initial stamping temperature, a new method named RCP method was proposed to improve the hardness and springback of hot stamping product in this paper. The cooling rate control before stamping is applied based on CCT curves through a rapid air cooling device which can provide cooling rate of 60°C/s. Three parameters included initial stamping temperature, contacting pressure and dwelling time have been investigated in this paper. According to the experiment results, the hardness deviation is markedly decreased and the springback can be controlled within the threshold value ±0.5mm.

The civil structures of nuclear plants need to meet the most strict criteria in terms of safety and reliability not only during their design and construction, but during the duration of their life cycle. Regarding the specifics of nuclear plant operation the inspections of the said structures need to be fully non-destructive and visual inspection is the method mostly used. In rare occasions it is possible to obtain a material sample in the form of drilled powder or small diameter core. In this paper, an example of analysis of such material sample is given, showing the amount of information describing the structural material that can be obtained using state-of-the art analytical methods – X-ray diffraction (XRD), X-ray fluorescence (XRF) and thermic analysis (TG/DTA). The paper shows results for regular structural concrete and special concrete with enhanced capability of shielding ionizing radiation.

This paper is a detailed study on the recycled concrete two-way slabs with stud-shear reinforcement, failure mode and failure mechanism are given. Further, by using the ABAQUS nonlinear finite element software to simulate the punching failure of recycled concrete two-way slabs with anchor bolts.Through the reasonable choice of the material property parameters 、the geometric parameters、the boundary conditions to get the reasonable results. In this paper, the conclusion can be used to provide the basis and reference in improving the punching resistance and ductility of the recycled concrete two-way slabs.

The paper discusses selected aspects on numerical modelling of historical masonry structures. Linear elastic material models are mentioned first, and then non-linear models are discussed. The paper includes several examples of solutions which have been done with use of these models. There is also an example of results which can be obtained from anon-linear analysis of masonry structures. The finite element method is used for computations.

The extradosed cable-stayed bridge is a new type of bridge developed in recent year. The main girder bears most of the load with its great stiffness, while the cable tension can improve the force state of the girder. So it is really necessary to optimize the cable force to determine the internal force of extradosed cable-stayed bridge under the rational completion state. But the optimization methods commonly used are based on the cable-stayed bridge and not entirely suit for the extradosed cable-stayed bridge. The paper puts forward a new optimization method, which includes applying the unknown coefficient functions aided by MIDAS/CIVIL, taking the reasonable feasible range of dead moment solved by stress balanced method as the constraint condition, making the square of unknown coefficients as objective function, and solving the cable force based on the effect matrix method thus to determine the cable force in reasonably completion state. This new method is verified with favorable effect, the internal force of this structure appear significant improvement. And finally, the results show better cable force obtained under the method in this paper compared with the cable force under other constraint conditions and objective functions.

The paper summarizes results of pilot fatigue testing of concrete slabs resting on granular base in testing box. The project aimed at verification of recent findings that fatigue resistance of concrete slabs is much higher than that predicted by using concrete fatigue characteristics from beam testing. Paper presents additional testing results that confirm enhanced fatigue resistance of concrete slabs. Further research is envisioned to supplement pilot testing results and to receive new results also on fatigue resistance under concrete recycling scheme.

In the current design of the traditional eccentrically braced steel frame systems, the link is a portion of the floor beam. The link damages because of absorbing energy firstly during an earthquake, therefore, the ability to repair the floor beam is very different, disruptive and costly and may affect the normal use of buildings because of the long repairing time. In addition, it is difficult to assess the extent of its damage, so we don't know whether the structure can survive under another earthquake. To solve these drawbacks, on the basis of this traditional eccentrically braced steel frame, the paper proposed a concept of the replaceable shear link which consisting of two channel sections bolted on either side of the web of the connecting floor beam (which called the new replaceable shear link thereinafter). The advantages and working mechanism of the new replaceable shear link were introduced in this paper, energy dissipations of the replaceable shear link and hysteretic behaviors of the eccentrically braced steel frame with replaceable shear links were analyzed under the cyclic loading by the finite element analysis software of ABAQUS. From the results of the analysis we can see, the new replaceable shear link has good seismic performance and deformation performance.

Almost all high-rise buildings have been constructed in the Republic of Armenia for past twenty-five years are Reinforced Concrete (RC) shear wall–frame structures, where shear walls provide most of the stiffness of buildings. The walls in these buildings are designed to sustain earthquake and wind loads. Vulnerability of them during earthquake action depends on many different factors. Some of them are the openings and its location in the walls. Usage of ground stories as parking and garages is demanded large openings in shear walls therefore determination of ultimate sizes of openings is important problems for designers. In this paper, FEM (Finite Element Method) models are used for investigation of stress-strain state of RC wall–frame buildings with various openings in the walls under action of seismic forces. Limitation of size and position of openings are considered in the paper taking into account of building code of Armenia. Various schemes of openings are considered in the article. The existing experimental data of shear walls were performed in various laboratories have been compared with our numerical investigation of RC models based on nonlinear computer analyses. Dynamic analyses of structures using accelerograms are showed sequence of damages in RC wall-frame models. The recommendations for limitation of ratio area of an opening to the whole area of a wall are proposed at the end of the article.

Wood is a material of construction relatively inexpensive and easy to put into practice because of its lightness, reusability, simplicity in fabrication and environmental compatibility. However, its ability to lift load small compared to other building materials, it greatly limits the range of its use. Increasing the mechanical strength of wood elements used in construction is a goal that, once achieved, would expand the use of this material, with notable economic repercussions. The use of composite materials such as CFRP (carbon fiber reinforced plastic) as reinforcement for wood elements under bending loads like beams requires attention to the techniques of reinforcing for different layouts of CFRP elements. Each choice of reinforcing could potentially lead to different results. When the choice has been made, the next step is the selection of the most adequate CFRP elements. For this reason, selection of the reinforcement layout and material should be guided by an accurate analysis of the characteristics of the element to be reinforced in order to avoid ineffective interventions. The present paper is concerned with determination the performances of wood beams reinforced with CFRP composites by investigating their bending resistance and showing crushing damage in the bending region. All tested wood beamspresented in this paper were made from beech. The results for the un-reinforced beams are reported solely for the purpose of quantitatively evaluating the effectiveness of the interventions through a comparison with the results for CFRP strengthened beams. The technology of composite material reinforcement is based on using CFRP plates bonded with an epoxy resin on the wood beams. After bonding, the beams were tested to bending on a universal testing machine with a punctuated force placed at the middle of the beams. The results indicate that the behavior of reinforced beams with CFRP is totally different from that of un-reinforced one. During the performed tests, observations of the experimental loaddisplacement relationships showed that bending strength increased for wood beams reinforced with CFRP compared to those without CFRP reinforcement. Mechanical tests on the reinforced wood beams proved that CFRP materials produced flexural displacement and lifting increases of the beams that entitles us to say this kind of materials have improved the mechanical performances of tested wooden beams.

Together with the rapid development of high-speed railways, extensive research into railway technologies is compulsory, especially on the aspect of dynamic interactions between vehicle and railway line, in order to guarantee the operational security of vehicles at high speed and improve the passengers comfort. The increase in the severity of the dynamic interaction between wheel and rail arises from the increasing speed of trains. As a result, it is necessary to analyze for the characteristics of wheel-rail vibration. The curve is an important component of a railway line and is usually the very source of wheel-rail vibration, especially at the time when a vehicle rapidly passes through a railway line, and will seriously affect the safety and comfort of the vehicle. At present, the usual practice is to only take some limit values to design the vertical section of railway lines, such as the maximum slope and the minimum slope length, according to the grade of a certain right line. Moreover, the existing studies on the vertical curve focused more on the vertical section parameters without considering the influence of these parameters on the dynamic interaction between the vehicle and line. The aforementioned studies involve either static or quasi-static analysis. There is little literature available on using a systematic method based on dynamics to study wheel-rail vibration, and some related issues are mainly the assessment making for a certain line. Based on the multi-body dynamics and the existing achievements, this paper aims to systematically investigate the influence of vertical section parameters on the characteristics of wheel-rail vibration and discuss the relationship between the acting region of wheel-rail vibration and these parameters. Furthermore, the characteristics of wheel-rail vibration at different velocities are investigated. The evaluation of the vibrations behavior in a railway vehicle is one of the matters taken into consideration even from the design stage. The decrease of vibrations to an acceptable level in terms of running behavior, safety, passengers comfort and track fatigue is required by regulations at European level for vehicle homologation and their admission into traffic.The vibrations of railway vehicles are mainly produced by the interaction between the track and the rail. Regarding a track with irregularities or deviations from the ideal geometry it creates vibrations of vehicles, which are developed both vertically and horizontally. These two types of vibrations are decoupled, though, due to the construction symmetries (inertial, elastic, plastic, linear and geometric). As for the vertical vibrations, the bounce and pitch vibrations are the main reasons of the vehicles dynamic behavior. They can be studied on simple models, one or two degrees of freedom, based on the hypothesis of excitation symmetry, by considering only one mobile base as if the wheel-sets had identical motions . This is the reason why the results with these models can be overestimated.This paper presents the influence of vehicle wheel bases and of the steel tire in running conditions, depending on some geometric characteristics. The influence will be further reflected by the vehicles response to the crossing over the rolling track random irregularities and in the magnitude of the vertical accelerations. This is the reason why the complete model of a passenger vehicle has been accounted for, including the car body bending vibrations. The movement equations have been treated in an original manner and brought to a form that points out the symmetrical and anti-symmetrical decoupled movements of vehicle and their excitation modes.

This paper deals with the determination of linear thermal transmittance for buildings with acute angle shapes. Calculation of linear thermal transmittance is a standard problem in determining the influence of thermal bridges on the overall energy performance of buildings. Computational methods are known for ordinary rectangular buildings and the values of typical detail are listed in databases. Current architecture of designs buildings uses acute angle shapes quite frequently. It corresponds with new trends in architecture. In such cases the value of linear thermal transmittance is not accurate for using databases. This paper presents an analysis of the influence of the change of angle of the walls in corner to linear thermal transmittance. It provides information applicable for buildings assessment in engineering practice.

This paper proposed a method to analysis an external flow-field around a Formula SAE car. Firstly, the body of Formula SAE car was designed conforming to the FSAE rules using CATIA. Then, the model of the external flow-field around the vehicle was established using computational fluid dynamic technology. A comparative analysis of the aerodynamic characteristics was made for the body between the conditions of being without the wing package and being with the wing package under different attack angle to get the static pressure graph, the lift force and the drag force then worked out the drag coefficient and confirmed which is the most suitable angle for the wings. The results showed that: the static pressure of the front body, the front part of the tires and the driver’s chest and head is the highest; the body has good streamline since its drag coefficient is 0.385; the rear wings can supply 65% downforce, when the attack angle of the rear wing is set to 8°. Finally, the real mold was fabricated according to the above 3D model and the analysis results. The method presented in this paper can provide theoretical basis and technical parameter for the aerodynamic formation designing and amelioration of the Formula SAE cars. Also it has guiding significance for the design and aerodynamic analysis of the Ordinary Passenger car.

Numerical simulations are powerful tool for analyzing and research in domain of mechanical constructions. In welded joints is very important to determine residual stresses and temperature distribution in sample, apropos, element of construction. In some cases doing the experiment is not possible, so numerical simulations can give the required results and overview of stress state, residual stresses, critical areas, displacement, temperature distribution and other data is needed for analyzing and improvement of constructions or parts of constructions. This analysis includes finite element model for the thermal and mechanical welding simulation. Welding simulation was considered as a sequential coupled thermo-mechanical analysis. The residual stress distribution and magnitude in axial direction was obtained. The paper also shows the results obtained in a simultaneously test of a butt welded thin steel sheet specimen by conventional methods and thermography. Numerical methods are also used in order to predict the crack of specimen. The obtained results confirm that it is very useful to use thermography and Finite Element Method (FEM) for early diagnostics of the complex structures in the exploitation conditions. In this paper is obtained good agreement of results between experiment and Numerical simulations.

The paper presents a case study on the original solution of a flange shaft as part of the root area of a 5 kW wind turbine blade. There were analyzed the causes that led to the shaft breakage under wind loadings in extreme weather conditions, and consequently technical solutions have been searched in order to improve the shaft design making it more reliable as mechanical strength at extreme wind loadings. The flange shaft is a welded subassembly that keeps the blades attached to the rotor hub. The first part of the paper consists in an analysis referring the loading status, the materials used for blade manufacturing, the identification of critical areas where the breaking was initiated and also the causes for which the materials assumed and specified in the technical design and manufacturing technology failed under loading at wind gusts of about 30 m/sec. Based on this preliminary analysis, the second part of the paper presents the technical solutions which were considered in reference to the materials and the improved design concept aiming to provide the right mechanical strength necessary to withstand specific wind loadings in extreme weather conditions.

In this paper, the application background and function of vibration test is introduced. Besides, the composition and working principle of vibration test system is also introduced simply. Furthermore, the characteristic of water and oil is compared with each other in the paper. It is discussed if the water hydraulic is able to be used in the hydraulic vibration test-bed or not. The capability of hydraulic vibration test-bed based on water is simulated by Matlab software. The feasibility of this project is also analyzed.

Using supplemental energy dissipation devices into the structure to increase the damping ratio for reducing the responses of seismic activity has become more and more popular. This paper presents a case study of seismic retrofit strategy, utilizing a type of passive energy dissipation device, namely, the viscous damper, in order to make an ongoing chips produced facility resistant to seismic activity. The building in question was a chips produced facility belonging to a semiconductor manufacturing company. This was a double FAB where the structure system was divided into an island building and an RC shell. The retrofit involved installing 44 non-linear dampers between the island building and the RC shell. This was due to the significant differences in the fundamental vibration periods. This paper will present the rationale of making a decision on the parameters of the dampers to give the optimum retrofit strategy.

Reverse engineering is a specialization which was developed a lot in the 21st century. The major aim is researching and describing the principals and procedures of process and structures. Reverse engineering in civil engineering is used to describe the applied loadings which caused corruption or failure of a structure or it is used to reconstruct 3D models of the original object. The aim of this paper is to compare response to static and impact loading of two materials, i.e. plain concrete and high-performance concrete (HPC), with respect to the fracture surface area. These areas were scanned by the 3D laser scanner and they were evaluated in the graphic programs. The main objective of this paper is a presentation of measured data, which can be used to determine the size of the applied loadings using reverse engineering.

The derrick of a drilling ship is a kind of dynamic ocean derrick which is often applied to drilling operations for ocean engineering. Comparing with land rig derrick, the operating environment of drilling derrick is more complicated with not only the regular functions of static force but also the dynamic loads induced by wind, wave and current. Therefore, this paper takes a drilling derrick as example to make clear of the dynamic characteristics of the drilling derrick under the action of dynamic loads from outside environment with the finite element software ANSYS as tool to accomplish the modal analysis of the drilling derrick. According to the natural frequency and the vibration mode of the drilling derrick after modal analysis, the deformation response and the weak parts of the drilling derrick under different motivation can be predicted, and some improving suggestions can also be illustrated as well. This paper completed the dynamic analysis of the drilling derrick by modal analysis, and moreover, the displacement response and the stress of the drilling derrick varied with time can also be obtained. As consequence, the conclusion can be taken as reference for design of the drilling derrick, safety application and life sustainment.

This paper discusses numerical modeling of strengthened masonry pillars. The main aim of the article is to study a usability of the proposed numerical models for evaluation of behavior of strengthened pillars. Maximum stresses are evaluated in order to identify the possible masonry damage initiation. The paper mainly discusses 2D numerical models of pillars in several alternatives. References to 3D modeling are also given. The in-house developed software uFEM is used for most of the computations..

The paper deals with the boundary state of the load-bearing capacity of a fragment of a slab-column structure in an emergency situation caused by the removal of a support at its corner. The paper presents the results of tests concerting the investigated element with the dimensions of 4000×4000×100 mm. Next, theoretically suggested mechanisms of the corner support have been dealt with, describing the behaviour of a slab-column structure after the removal of the support at the corner. The aim of the paper was to compare the results of test carried out in the laboratory with the values obtained by analytical calculations. The results of this analysis have been gathered in the summary.

Wind turbine blades are the major structural element and highest cost component in the wind power system. Modern wind turbine blade sizes are increasing, and the driving motivation behind this is to increase the efficiency and energy output per unit rotor area, and to reduce the cost per kilowatt hour. However due to the increase in size the material selection for wind turbine has become critical and complex. To achieve the desired materials to improve the design of wind turbine blades several factors such as high fatigue strength, less weight, less cost and potential of recycling must be focused. Basalt fiber is a relative newcomer to fiber reinforced polymers and structural composites. Basalt fiber with their excellent mechanical properties represents an interesting alternative composite material for modern wind turbine blades. Some manufacturers claim that basalt fiber has similar or better properties than S-2 glass fiber and its cheaper than carbon fiber. Basalt fiber together with carbon fiber are the most advanced and interesting area of hybrid technologies. This paper reviews extra ordinary properties of basalt fiber over other fiber reinforced composites and highlight how the basalt special properties together with carbon fiber will reduce the weight and cost of wind turbine blades while improving their performance. This paper also demonstrates why the basalt carbon hybrid composite material will be an ideal alternative for the wind turbine rotor blades.

The calculation of stress intensity factor (SIF) in fracture mechanics-based fatigue life prediction is mainly based on empirical formulas, the poor applicability of which limits the wide application of fatigue assessment based on crack propagation. This paper proposed a SIF calculation method for structures under wave loads. It was proved correct by comparing with the empirical formulas. Then, the method proposed was applied for the surface crack at weld toe of a connection between the column and brace of a semi-submersible platform. The predicted results showed that SIF ranges varied with wave loads, which were subjected to the effects of wave directions and frequencies. In addition, SIF ranges calculated by empirical formulas were very different from those of the proposed method. In order to accurately predict fatigue crack propagation life for ocean engineering structures, it is necessary to take the characters of wave loads into consideration. The proposed method in this paper may provide a reference.

The paper deals with a numerical analysis of timber-concrete ceiling. The finite element method is used for the analysis. The calculation takes into account a dynamic effect of load. The structure creates the ceiling of the gymnasium. The goal of the paper is a study of ceiling eigenfrequencies and a maximum response to a harmonic excitation.

Solar powered UAV has the characteristics of high aspect ratio, low structural surface density, high structural flexibility and low flutter speed. Different solar array mountings will affect the flutter characteristics of the structure. The mechanical properties of solar arrays packaged and unpackaged are measured in this paper and the solar powered UAV structural finite element model based on Patran/Nastran was also established in the paper. Two solar array mounting ways are researched: embedded solar arrays and patching solar arrays. To investigate the flutter characteristics under the two solar array mounting ways, the Doublet lattice method (DLM) aerodynamic model is used to model the unsteady aerodynamic loads. Finally, flutter speed of the structure was determined by using the P-K method and the analysis result indicate that patching solar arrays is more conductive to improve the flutter characteristics of the structure.

The paper deals with the mechanical response of a pre-stressed railway sleeper during a standardized static loading test estimations of the variability of the sleepers response and especially the probabilities of the occurrence of cracks of specific widths at specific load levels (as a consequence of random concrete parameters) based on the results of (3D) numerical models are presented. The paper follows on from and extends previous results obtained by the authors research team in cooperation with specialists from the sleeper manufacturing company ZPSV a. s.

These paper aims to determine the influence of the most important geometrical parameters (vertical step and punch diameter) on the main strains, thickness reduction and the forces along two directions during the single point incremental forming process (SPIF). The paper comprises a comparative numericalexperimental study, for a simple geometry part obtained by incremental forming. In fact, in the first stage, the punch has a vertical motion with the value of one vertical step. In the second stage, the punch follows a linear trajectory along one side of the die. After each linear trajectory the punch has successive vertical motions, taking one vertical step at a time until the entire geometry of the part is done. In order to study the influence of the geometrical parameters, to the vertical step and the punch diameter were assigned three levels of variation. Following the selection of these geometrical parameters values, a factorial experimental program of type 32 has been adopted. The maximum values of the main strain and thickness reduction rises with the decrease of both vertical step and punch diameter and the maximum values of the forces are reached with the increase of both vertical step and punch diameter.

In the present paper, the finish-blanking method is taken up because it is an easy-to-use method by using a tool with rounded edge and a small clearance between the punch and die. In finish blanking, the process parameters such as the tool shape and clearance are significant. The purpose of the present work is to clarify the effect of tool shape of PW punch in finish blanking. In the present paper, a high-tensile-strength-steel plate with a thickness of 6mm was used. The edge shape of punch was changed, and the clearance was changed within the range of 0.65%t - 12%t. The experimental results show that the edge angle of PW punch should be in the range of 30° - 60°, and the clearance should be less than 2.0%t to obtain the ratio of the burnished surface more than 80%. The edge shape of the punch has a very limited effect on the shear droop, when the clearance is less than 2.0%t. It was also found that the PW punch is more suitable to control the burr depth than Rounded punch.

The research background is the pile foundation concrete formula design of transmission line, the foundation of construction site is high-corrosion circumstance in western of China. The target of this paper is to propose a concrete formula which can resist the compound attack of sulfate and chloride. Firstly, compound solution was made up to simulate the groundwater corrosion circumstance. Then, the following tests were carried out: sulfate solution attack test, groundwater attack test, chloride ion permeability test and compressive strength test under different curing environment. Many concrete formulas were pre-designed according to the different cement chemical compositions and the admixture quantities. After optimization, the adaptive formula was obtained. The scheme and results in this paper can be extended to similar studies on corrosion-resistant concrete.

Nonlinear finite element method is used in this paper to research the ultimate strength characteristics of aluminum stiffened plates under uniaxial tension-compression cyclic loading. This paper focused on the effect of the distribution mode of HAZ, the range of HAZ and different cyclic loading process on the ultimate strength of aluminum stiffened plates. The results obtained have a certain reference value to the design and manufacture of aluminum stiffened plates.

Paper deals with practices significantly affecting quality and durability of external thermal insulation of the building envelope. Analysis is made by the survey of existing external constructions of buildings, experimental detection of bearing capacity of expansion anchors, including theoretical modelling of their activity in the external wall processed by the ANSYS program. Paper briefly summarizes new findings detected by control and testing activities for additional thermal protection of the building envelope.

Rubber hose is normally adopted in the connection between the lifting cylinders and the control valves. Low bulk modulus of hose reduces the natural frequency of hydraulic system and brings difficulties to the controller design. This paper focuses on the model simplification of hoses in the hydraulic system. First, a hydraulic lifting system is presented in the paper. Then, simulation model of the lifting system is built in AMESim, and the simplified model of hose is conducted using an improved lumped parameter method. Finally, comparative simulations with the proposed model and the original model provided in the software are carried out. Results show that the simplified model can be used to replace the original model in the simulation of hydraulic systems.

Considering the features of slope rock mass failure, this paper applies residual thrust method and linear programming theory on the basis of finite element method, to assess safety of each cell of slope rock mass in dangerous zone. According to the slip field method to determine three-dimensional slope slip surface, to deduce three-dimensional stability analysis method based on symmetry breaking, a C++ based 3D-slope program is developed for purposes of three-dimensional slope stability analysis. Finally get the most dangerous landslide geometry and its safety factor, In the paper, combining with the engineering examples, the calculating results are comfortable to the practical failure.