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A device has been designed to measure the whole stiffness which is behalf of paper plate’s carrying capacity. When the device was working, one end of the paper plate was hold as a hand did, the other end of the paper plate was pushed to 15°angle from the horizontal surface, and the force on the paper plate was recorded. Comparing load-bearing performance, the whole stiffness is more accurate to reveal the differences of the paper plates.

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.

Ground Penetrating Radar is a method using high frequency impulse electromagnetic wave to detect underground media distribution. It has been gradually widely used as it has the advantage of high accuracy, fast and nondestructive respecting to the conventional method such as visual measurement and confirmation with drilling hole. In the tunnel construction process, it is easy occurred that the quality problem of insufficient lining thickness, the distance of steel arch centering too large and the concrete disengaging. The work achieved in this paper based on the project of LongSheng tunnel and its conclusion and suggestion has important practical engineering significance.

The complex nonlinear problem exists between the factors which influence the strength of hybrid fiber reinforced concrete. The nonlinear relationship between input variables as the factors and output variables as the strength can be obtained artificial neural network which have the feature of self-adapting, self-studying and nonlinear mapping. RBF and BP neural network models are established in MATLAB in this paper based on experimental values. Compressive strength and flexural strength of hybrid fiber reinforced concrete are predicted respectively and comparing with the measured values, predicted values are analyzed. The results show that the predicted values based on RBF tally with the experimental values, and the strength prediction ability of RBF is higher than BP neural network. The needs of engineering can be meet by this method with accurate prediction ability, a new method for the study of hybrid fiber reinforced concrete strength is provided.

In order to solve the problem of multi-index amalgamation on the reliability evaluation for tunnel lining with cracks, this paper based on extension theory, use matter element model theory to establish the matter element of the reliability evaluation for tunnel lining with cracks, use the dependent function to establish the relevance between matter element and reliability grade, combine the research result of the Beiru tunnel lining cracks disease to evaluate the reliability. The results show that it could consider the multi-index of the cracks to use the extension theory to evaluate the reliability of the tunnel lining with cracks, and the evaluation results are more scientific and reasonable. It is viable to use the dimensionless parameters to represent the crack geometry. In the K6, the treatment scheme is mechanical reinforcement. In the K2 and K3,the treatment scheme is surface sealing. The reliability evaluation results supply theory basis and technical guidance for the tunnel long-term health service and the disease treatment.

Brackets is the ancient Chinese wooden building unique ways and one of the main features of the structure. Its dual function of both structural and architectural: An important component of both the structure itself, because of its flexible features tenon, the dynamic response of the structure can absorb greater energy, play a good role in the earthquake; But it is also a special architectural ornament, can play the effect of beautifying buildings. Therefore, this paper based on the finite element software ABAQUS brackets by the force of the mechanism of failure modes and numerical simulation analysis for the brackets and the whole structure of the wood to provide a scientific assessment and reinforcement.

The spiral shaft parts have been widely applied in machinery and equipment manufacturing industry, the paper based on DEFORM-3D, the rigid-plastic finite element model of cross wedge rolled spiral shaft parts was established. The rolling process was simulated, the strain laws were analyzed, and the characteristics of metal flow were explored. From which we can find Plate cross wedge rolled spiral shaft parts is completely feasible. The results provide the theoretic basis for precision deformation of cross wedge rolled spiral shaft parts.

Wood is a renewable source of structural material with high relative strength/weight, low energy production, which kidnaps and stores carbon in its production. The large use of wood is due to its special qualities as raw material for other products manufactured in residential construction or major works such as bridges, has been widely used in roofing for industrial and commercial buildings. Commercially there are limitations on the length of the wood, resulting from the extraction of tree trunks, thus requiring the adoption of binding elements is the use of self-tapping screws efforts required by side and which can be axial, shear, tensile or compression. Whereas in Brazil does not yet exist and the promising future of the product, this research aims to study the behavior of self-tapping screws together with Brazilian reforestation species ofPinusoocarpaandLyptus(softwood and hardwood). Rothoblaas self-tapping screws had a good penetration in both woods without requiring pre-drilling, the species of Lyptus wood showed the highest values of strength and the inclination of the screws, at 45 degrees showed the best results on either species of wood.

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 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.

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.

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.

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.

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.

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.

To further improve the material utilization in cross wedge rolling, the paper simulated the forming of closed cross wedge rolling through DEFORM-3D, a rigid-plastic finite element analysis software, and analyzed the distribution and changing rule on the fields of strain and displacement in the parts rolling. Then the paper clarified the generated mechanism about the end concavity of shaft in the closed type of cross wedge rolling, which has great theoretical significance and engineering applied value in controlling and decreasing the end concavity in closed type cross wedge rolling and improving the parts’ end quality.

In order to raise the efficience of materials' utilization and realize the CWR without the stub bar, this paper will focus on the closed CWR forming shafts,applying finite element software DEFORM-3D to do numerical simulation calculation for the process and studying the end quality of shafts.This paper has obtained the influence rule of the forming angle α, broadening angle β, reduction of area ψ and billet diameter D four process parameters on the end quality of the closed type CWR .The research results has showed that the length of concavity goes up along with the forming angle decrease;the same as the broadening angle; while the length of concavity goes up along with the billet diameter increase.and the reduction of area ψ has made a vital influence on the end quality of shafts,this conclusion has made a solid theoretical foundation and referential value for closed CWR .

The paper applies composite technology into the field of hydraulic metal structures and hydropower construction mechanical equipment design, and presents the method of optimum design of hydraulic steel gate metal sandwich construction and simulation analysis. According to characteristics of the structure of the flat hydraulic steel gate and selecting the appropriate metal sandwich construction, this paper optimize the design of a hydraulic steel gate of metal sandwich construction from the perspective of light-weight purpose of structure. Considering the overall mechanical behavior of steel gate structures and using technology of three-dimensional modeling and numerical simulation, this paper has a numerical simulation analysis on the optimum hydraulic steel gate. Numerical simulation analysis and theoretical calculation results show the optimum structure of hydraulic steel gate is reasonably practicable.

This paper focuses on the research carried out on thin plates made of white ultra-high performance concrete reinforced by PVA fibers and 2D textile glass reinforcement. These boards should be used for facades or roof panels. The paper presents a computer and experimental analysis of the loading of thin UHPC plates. For the purpose of the experiments, three specimens of a size of 750 x 125 x 15 mm were made. The specimens were subsequently tested in the laboratory in four-point bending tests. The paper presents the process and results of the experiments. Simultaneously with the experiments, computer analyses were created in which optimization of the material and geometric parameters of the beams were carried out. The paper demonstrates the correspondence of the experimental and computer-simulated load test results.

Based on the static elastic-plastic analysis program REPFPA, the impact of concrete material elastic-brittle-plastic damage model and its numerical test methods was studied. This paper has introduced the visualization technology, preparation of pre-processing related modules and graphical visualization display and many other functions into the nonlinear dynamic program, which is convenient for users to operate and view the results. And the numerical experiments of dynamic response of cantilever beam problems and spherical shell under step load elastic-plastic problems was produced. Compared with the results of other scholars and literature, we’ll verify the validity of the research in this paper.

This paper introduces a new technique to test fatigue cracks in concrete that occur during its maintenance. The principle of the technique consists of exposing the object to pulsed mechanical excitation. As a result, acoustic waves start to propagate in the sample. Under the action of acoustic waves the dipole moments of double electric layers on the boundaries of components in concrete are changed and piezoquartz which is a part of sand and gravel is polarized. The external electric field occurs and is registered by a signal receiver placed near the object under study. The possibility of using this technique for crack nondestructive control is studied in the paper. The technique capabilities are shown by comparing the parameters of electric response on pulsed mechanical excitation when testing the defectless concrete and the same sample after developing the artificial crack in the concrete.

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.

In this paper, some numerical verifications would be presented and discussed, mainly including the following three types: (1) the pure bending beam in which the structural stiffness would maintain the original value and not change along with the load; (2) the clamped arc-beam in which the structural stiffness would decrease gradually with the increment of load and the structure would be buckling at some certain load value; and (3) the cantilever beam in which the structural stiffness would increase significantly with the increment of load. For all of the above examples, the present results are in good agreement with the analytical results and numerical results in other literatures, testifying and illustrating the validity of the large rotation matrix for nonlinear framed structure, which is developed in the part 1 of this paper.

The failure criteria and calculating methods of static and seismic shear strength of masonry under combined shear-compression action have been researched in this paper. According to the least energy consumption principle and the failure criteria of orthogonal anisotropic materials, the correlated formulae of masonry under combined shear-compression action are established. The correlated formulae are in good agreement with experimental results. On this basis, the calculation formulae of the static and seismic shear strength are established. The calculation formulae uniformly use the axial compression ratio as main variable to express. By analyzing examples, it shows that calculations by formulae given in this paper are in accordance with values of "Code for design of masonry structures" (GB 50003-2011) and "Code for seismic design of buildings" (GB 50011-2010). The methods in this paper may provide important references to engineering design as well as code revision.

This paper presents a reinforcement design of five-story R/C structure with mild steel dampers in high seismic fortification intensity site. The details of the design process are listed in the paper, and the time history analyses under frequent and rare earthquake are performed on structure models with and without dampers. Through the comparison, the peak of maximum story drifts angles with damper-added structural is reduced by 38% and the distribution is more uniformly. The results show that energy-dissipation design with mild steel dampers can be a reliable and effective method in reducing seismic responses of reinforcement structure.

The study on the calculation of the security of high concrete arch dam based on the finite element method will be studied and analyzed in this paper. For high concrete arch dam deformation and stability under normal water level and maximum flood level will be calculated, and the stress of each section of the dam and batholith around will be checked and analyzed, then this paper will come to the dam security conclusion finally.

Stayed-cable was being considered as an important component of cable-stayed bridge, with characteristics of its low quality, stiffness and damping, among which rain-wind-induced vibration brings the most serious damage in its high amplitude because of its easy conditions to meet. This paper based on the theory of stayed-cable rain-wind-induced vibration, Through comparing different aerodynamic control measures in wind pressure test of ZhiJiang Bridge cable, this paper analyses the variation rules of two and three dimensional cable surface pressure distribution in different aerodynamic measures and cable aerodynamic coefficient in different surface conditions. The results show that: the wind angle influenced surface wind pressure coefficients and aerodynamic coefficient larger, especially between 25 ° and40 °; when the water was between 40 ° and70 °, the aerodynamic coefficient changed obviously, may happen galloping; It recommend that the cable helix parameter K1 was larger and K2 was between 0.01 and 0.03.

Through site test, the paper conducts site test to vertical vibration accelerations when a train passes through steel rails and tunnel walls at a steel spring floating slab track section and a general track section in the tunnel of Yizhuang Line of Beijing Metro. The paper also conducts comparative analysis of the accelerations in time domain and frequency domain. It is shown in results that the vibration acceleration level of the steel spring floating slab track in time domain is reduced by 22 dB in tunnel walls in comparison with the general track; in the frequency domain, the vibration effect is gradually increased with frequency increase and reaches the optimal effect in medium-high frequency. The maximum vibration attenuation quantity of frequency division reaches up to 40 dB; and the maximum Z weighted vibration acceleration level is reduced by 22 dB.

On the basis of monitoring surface deformation in some area subject to large transmission line tower base hazard, monitoring method description, monitoring data sorting and calculation of characteristic parameters for surface deformation are conducted to obtain relevant conclusions of the transmission line tower base deformation by sorting and analysis of monitoring results in this paper. Calculation, analysis methods and conclusions of this paper lay a foundation for analysis on stability of the transmission line tower base and provide a basis for design of the transmission line.

Steel silos are commonly constructed by welding together a large number of curved steel panels with lap joints.Where the lap runs horizontally around the silo circumference, the lap connection causes a local eccentricity in the line of vertical thrust in the shell wall. This eccentricity induces high local bending stresses, which are detrimental to the stability of the structure. This paper chooses a flat-bottom squat steel silo as the research object to analyze the stability of lap-jointed steel silo by comparing with a butt-jointed steel silo. By stressing loads calculated according to Chinese code for design of grain steel silos, considering two load cases including axial compression only and combined axial compression and internal pressure, this paper performs numerical analysises including linear buckling analysis, geometric nonlinear elastic analysis and geometrically and materially nonlinear analysis to study the effects of material nonlinearity and lap joint on stability.

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.

Concrete mechanical properties under dynamic load such as blast and impact are very complex. Shock wave propagation law and damage effect in the concrete were studied numerically in the paper by using TNT explosive ignition and growth model, concrete dynamic damage model, and SPH method. And shock wave properties of different mass explosives in the concrete were analyzed with the similarity theory. The result shows that TNT shock wave propagation law meets the internal-blast similarity law. Peak pressure, positive pressure impulse, maximum velocity and maximum acceleration in the concrete decrease with the increase of scaled distance. And time needed for reaching peak pressure increases linearly with the increase of scaled distance. A theoretical basis of structure and protection design for constructions is achieved in the paper.

In the paper, according to crushing and attrition of material on mixer blade, the mechanical model of material on blade is established. According to nonlinear vibration and the basic theory of rotor dynamics, Mechanical model of vibration system and differential equations of motion are established. This paper has adopted the arithmetic of fourth-order Runge-Kutta, analyzing wave forms graph, chart of axis track, phase plane plot of system movement. Analysis results show that mixer system appears chaotic motion under some certain design parameters. This state of motion on mixers can better destroy cement coagulation group, increasing the number of effective collision of concrete particle, which can effectively improve the microscopic homogeneity of concrete and improve efficiency of concrete mixing.

The paper deals with the back analysis method in geotechnical engineering, that goal is evaluation the more objective and reliable parameters of the rock mass on the basis of in-situ measurements. Stress, deformational, strength and rheological parameters of the rock mass are usually determined by some inaccuracies and errors arising from the complexity and variability of the rock mass. This higher or lower degree of imprecision is reflected in the reliability of the mathematical modelling results. The paper presents the utilization of direct optimization back analysis method, based on the theory of analytical functions of complex variable and Kolosov-Muschelischvili relations, to the evaluation of initial stress state inside the rock massif.

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.

Due to the trend of miniaturization on electrical devices, medical devices, and energy, etc., the need for micro and mini metal parts is increasing at a tremendous rate. In order to realize the potential of the mini-parts and take advantages from the mini-forming process, innovative modifications of the forming process must be developed. These modifications are particularly important with respect to the mini-parts forming, which offers an excellent opportunity to produce high accurate mini parts and to reduce manufacturing costs and time. However, severe modifications of the material thickness occur during forming of mini-parts. This paper presents a study concerning the material thickness variation during forming process of mini-parts. The main objective is to understand the material behaviour during forming of mini-parts. The material used in this analysis is copper - zinc alloy with anisotropic properties. During forming process of conical mini-parts, the material become very thin around the punch radius and become thicker at the upper end of the part. This phenomenon cause forming problems such: material fracture, wrinkling, part diameter variation, springback etc. There are multiple factors that affect the material thickness variation during forming process as: side wall angle, friction coefficient, punch radius, and punch speed. The Dynaform 5.9.1 software was used to simulate the forming process. The part obtained after each simulation was analyzed and measured to quantify material thickness variation on the final conical mini-part. To analyze the behaviour of the material during deep drawing process the obtained results for different conical mini-parts were compared. In the final part of this paper some conclusions regarding the material thickness variation during forming of conical mini-parts are presented.

Task of controlled ventilation in modern residential buildings is to ensure optimum quality of interior environment and fulfill hygienic and thermal technical requirements guaranteeing comfort of user. The paper discusses development and experimental verification of atypical vertical ventilation units of under pressure controlled ventilation system for residential high-rise building. Recommended concept of solution to façade detail in relation to ventilation system. Optimized alternative of air inlet openings in the bottom level of vertical pilaster with function of air distribution channel for under pressure controlled ventilation system. The paper discusses laboratory experimental verification of physical properties of optimized alternative of ventilation units of under pressure controlled ventilation system for high-rise residential building in their development cycle. Boundary conditions of physical designing of envelope structures for load of wind-driven rain and their modifications for high-rise building in the locality of Bratislava. Hydrodynamic regime of air inlet openings of controlled ventilation system – maintaining water impermeability of air inlet openings of the ventilation system under the effect of wind-driven rain – laboratory experimental research in large rain chamber, its results and necessary construction modifications of elements of ventilation units. Aerodynamic regime of natural controlled ventilation system – quantification of volume of air flow rate through ventilation units in dependence to air pressure difference - laboratory experimental research in large pressure chamber. Acoustic properties of natural controlled ventilation system – quantification of index of air impermeability of controlled ventilation system in open and closed position - laboratory experimental research in acoustic chambers. Comparison by the experiment of verified parameters of ventilation units of under pressure controlled ventilation with design parameters.

Deployable structures are new prefabricated frames that can be transformed from a closed stage or compact configuration to a predetermined, stable expanded form. The structure is very convenient for transportation and recycling because it can be stretched out, drawn back and disassembled into pieces easily. This paper describes a new deployable structure composed of scissor composite members, each of which consists of universal scissor components, connected by bolts, and braced by pre-tensioned ropes out-of-plane, conforming a stable system. An aluminum-alloy deployable model was fabricated and a test program was carried out under vertical load to evaluate the capacity of the structure. Numerical analysis using FEM was conducted for validation purpose. By studying the stability and capacity of the structure, comprehensive evaluations of the structure were made. Possessing several advantages stated in this paper, deployable structures can be used as semi-permanent and temporary large spatial buildings.

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.

Stratosphere airship envelope material is composed of multilayer laminated film material reinforced by fiber. As the same as other film material, it occurs del-zone in the course of crack tearing propagation, which is significant for envelope material mechanic studies. Many researched unlined its application, not it’s forming factors. The paper focus on crack or notch shape effects on the del-zone. Six groups test including specimen with no crack, central crack, square notch, diamond notch, circle notch, and rectangle notch are carried on under the stretching instrument to find the different del-zone phenomenon and get displacement-load curve. Combined with theory, the paper try to explain the del-zone differences for specimens and explore the shape notched sensitivity to specimen. The results shows that different specimen have differences on del-zone, further affecting the specimen module and fracture strength. In turn, it manifests that to some extent, the size del-zone decides fracture stress value, providing advice for airship envelope designing.