This article reviews shearography and its applications in nondestructive testing. Shearography is a laser-based technique for full-field and non-contacting measurement of surface deformation. Despite being a relative young technique, it has already received considerable industrial acceptance, in particular, for nondestructive testing. One major difference of shearography form other NDT techniques is the mechanics of revealing flaws. Shearography reveals defects in an object by identifying defect-induced deformation anomalies which are more relevant to structural weakness. Other applications of shearography include strain measurement, material characterization, residual stress evaluation, leak detection, vibration studies and 3D shape measurement.

In this paper, the electron bema moire method and AFM scanning moire method are proposed to measure the thermal deformation in the BGA electronic packages. Electron beam moire and AFM moire fringe patterns in the BGA package are recorded. The shear strain at different solders in the package is measured. The two measurement techniques are discussed and analyzed in detail. The adaptability of these two methods is compared.

Experimental characterization plays a significant role in the reliability analysis of electronic packaging and, therefore, is critical in package design and manufacturing. Experimental characterization deals with the material, process and design issues in electronic packaging to ensure processability and reliability. The reliability of a package should be sufficient to meet the manufacture process requirements and the product life expectancy under application conditions. As electronic technology advances, more novel materials are being used in packages and package sizes are becoming smaller and smaller. The components are typically structures with multi-materials and interfaces in a highly compact and integrated feature. The manufacturing process for the semiconductor devices and the related packages are becoming more and more sophisticated, involving numerous complicated steps. As a result, the process characterizations and reliability analysis are becoming more and more challenging. Together with many analytical and numerical methods used in this area, experimental methods have become more and more important. The experimental methods provide material properties which are needed in the theoretical and numerical modeling and for material selections. They are also critical in the areas of processes characterizations and failure analysis for design optimizations.

In this paper, phase-shifting moire method was employed to investigate the machining effect on the warpage of electronic packagings undergone thermal cycles. Four types of machined slots were tested and compared with the unmachined one. It was found that they all give significant improvement on the warpage. However, the crossed type slot gives the largest reduction of warpage.

With concern to engineering structures it is of increasing importance for safety as well as for economical reasons to control, whether changes in utilization, whether aging and fatigue of materials, environmental conditions, whether time- depending response etc. might affect the material as well as the structural response as e.g. stability, safety and service-life adversely. This can be done only by measurements, based on the principles of experimental mechanics, combined with proper algorithms for data-evaluation. Application of such methods is not restricted to basic research and material testing in laboratories. They have proved to be quite useful in remote control and health monitoring of technical structures, especially of those with high risk-potentials in case of failure. They should be applied to new as well as to already existing structures in order to get reliable knowledge on the behavior of structures over the whole life-span. As yet mainly methods of electrical measuring mechanical quantities are used in a wide variety of combinations. But nowadays different optical methods are available also, which are very precise and highly reliable in the long run, relative insensible against external influences, adaptable to almost any kind of problem. An overviews on different optical methods will given.

Structural Health Monitoring by some form of semi-automated process has been near the top of the engineers 'wish list' for many ears in order to monitor the performance of fatigue loaded structures. Many attempts have been made mainly by attempting to assess the actual load spectrum applied to the structure during service and appropriate fatigue analyses based on the results. While limited success can be claimed for this approach it usually has a weakness in that vital information may be lost in the event of electrical power being lost to the system. During the period of inactivity it is possible, for instance, to miss the 'hundred year wave or gust' as well as small events that would be incomplete and therefore inaccurate assessment of fatigue loading history. An entirely new approach is described in this paper that is insensitive to los of electrical power based on a 'modified acoustic emission' principle. Experimental mechanics procedures have led to a much more direct identification of fatigue testing of Aircraft Structures and then to develop it into a flying Aircraft Health and Usage Monitoring System.

The intelligent and information industries are rapidly developing and will have larger and larger shares in the GNP. Most components of these high-tech industries are made of small-scale low-dimensional materials, such as thin films, filaments and microstructure. As the thin film is one of the basic constructional elements, the scientific research in the thin film materials, especially for mechanical behavior research, attracts special attention. The mechanical properties of the materials that have microscale in the direction of thickness may be different form those of the microscale materials, but it is a valuable facto of working reliability for microstructure. So the experimental study on the mechanical properties, especially some of the basic nonlinear mechanical properties, is necessary and significant in constructing mechanical model, optimizing design, analyzing the quality and reliability of the components.

Nano-moire method is a technique based on the conventional moire method but using crystal lattice as grating. It has nanometer- order resolution. This paper introduces some applications of this novel technique on measuring crack tip deformation in silicon single crystal, the residual strain near an interface in GaAs/Si and deformation field near an edge dislocation.

To analyze fringe patterns, frequency and phase analysis of fringes becomes popular. It provides accurate results and automated processing. In this paper, the theories of the frequency and phase analysis methods using Fourier transform, Gabor transform, wavelet transform are introduced for shape analysis using gratin projection method, strain analysis using gratin method or iso chromatics and iso clinics analysis using photooelasticity. The applications of these methods are also described.

In this lecture, the process of wavelet transform (WT) is reported for the image patterns of photomechanics, that involve carrier fringe patterns and randomly distributed speckle patterns. For the frequency modulated carrier patterns, the results from wavelet transform are compared with that from Fourier transform (FT), which shows the advantages of WT in the solution of high graduate problems such as concentration of strains and localization of solid-liquid interface. For the correlation matching of the speckle images during deformation, the computation based on wavelet coefficient shows sharper correlation peak than the convenient algorithms directly based on gray levels. 2D WT is presented to process the displacement fields resulted from correlation to show the detection of the crack singularity in materials by the wavelet transformation.

Double-exposure holography and double-exposure shearography are two interferometric techniques that are particularly useful for precision measurement, and for non-destructive inspection and evaluation of the structural integrity of test objects. Quite often, objects with symmetrical deformation are tested and the challenge to the engineer is to check for symmetry in the deformation. While the holographic and shearographic fringe patterns are able to achieve this, it is felt that the inspection process can be simplified and expedite considerably if the engineer needs only to look for either the absence or the presence of fringes. In other words, a 'go, no-go' gauging method is desired so that the absence of interference fringes depicts symmetrical deformation and the presence of interference fringes depicts asymmetrical deformation. This paper demonstrates that this gauging method can be realized with the use of a commercial beam-splitting cube. By carefully orienting the beam-splitting cube, the image of the test object is brought to overlap, either fully or partially, with the mirror-image of the test object. With fully overlapping images, the relative displacement between two symmetrically located points on the test surface is obtained, resulting in the technique of self-comparative holography. This method is found useful in checking the symmetricity of deformation. With partially overlapping images, the relative displacement-derivative between two symmetrically located points on the test surface is obtained, resulting in the technique of self-comparative shearography.

In this paper, optical methods for the surface profile and deformation measurement of MEMS materials and structures are introduced. The methods are based on the digital image correlation, interferometry and fringe projection. The deformations of a micro-mirror and a micro-beam are measured by phase shifting fringe projection and interferometry. The surface profile of an electrode pad was used for the demonstration of the microscopic surface contouring. For the MEMS material test, using a long working distance microscope and digital speckle correlation method the tensile strain of a thin copper wire is measured.

The phenomena of Portevin-Le Chatelier (PLC) band propagation and its pulsation accompanying the serration of load curve in a tensile test of aluminum alloy were directly observed by using dynamic digital speckle pattern interferometry method. In the plastic deformation stage, a slip band is formed and propagates repeatedly along the tensile direction with a certain speed and a certain bandwidth. The propagation speed decreases gradually with the increasing of plastic deformation, and finally the specimen cracks at the position where the band stops. The same slip fringe patterns observed from the front surface and rear surface of the specimen simultaneously show that the slip plane goes through the thickness of specimen. Pulsation of fringe density in the inside of the slip band accompanying with the serrations of load curve was observed. The pulsation period corresponds with the width of the serration. When the load falls in the serrations, the slip deformation happens just like an avalanche, and the time of the avalanche slip is less than 0.03 seconds. Corresponding to the happening of the avalanche slip, dense shrinkage fringes appear on the outside of the slip band. The specimen takes a shrinkage deformation in the outside of the slip band to compensate the elongation deformation in slip band at the moment of avalanche slip, even for a tensile test. The elongation value in the inside of the slip band causing by the avalanche slip is in the order of 10 micrometers by calculating with observed results.

The high strength concrete of coal-grime has bad permeability, the traditional method of soak water can not give its permeability. This article introduces the method of resist Cl soak, which result in good effect.

The pattern presents an experimental method to investigate the displacement and deformation of rubber elements. Because of the large deformation feature, the moire method with co-moving coordinate is used in the experiment. The paper introduces the choice of experimental material, the loading means and the arrangement of grating. Finally, an example of lip-type sealing ring is given, the experimental result shows that the method is feasible.

A Digital Image Correlation technique is used to develop and validate a new biaxial compression set-up. Some experimental test have been performed under proportional and nonproportional loading conditions with the experimental set-up. During these test, a particular attention is paid to the appearance and the disappearance of martensite plates during the loading path. By using a long distance microscope with a CCD camera, we show the importance of the mechanical loading path shape on the martensite formation.

As a sort of multiple component, and dispersed state granule aggregation, frozen coal behaves similar to frozen soil. On the basis of its unique ice-cementation effect and not-frozen water along with dynamical balance state between the frameworks of mineral granule, the mechanical behavior of frozen coal is more complex than usual in compact medium, restrictedly with force amount, process time period and temperature. In all factors which impact on frozen intensity of frozen coal frozen with steel plate, water content is relatively easy to control. From results of this test research, values of frozen intensity is changeable under different water content. Up to the critical water content, the value of frozen intensity increase rapidly till a certain steady value. Under a certain temperature and water content condition, the granule component of frozen coal has somewhat effect on the frozen intensity. Usually, the frozen intensity of large granule coal is greater than the small granule's However, the distributing of coal granule size present a steady probability rule. So the effect from granule size is tiny.

This paper describes the modeling of the indentation of an elasto-viscoplastic material. The finite element code ABAQUS was used to study the bulk mechanical, thermal and interface frictional characteristics for rigid wedge indenters. A series of simulations has been performed at a constant velocity to prescribed depths of penetration for a range of wedge surface temperatures and semi-included angles. Selected experimental data are provided as a basis for validating the numerical simulation. In the simulations, the constitutive behavior of the model material Plasticine is treated as non-linear elasto-viscoplastic, in which the stress scales linearly with the elastic strain and non-linearly with the plastic strain rate. The result demonstrate that the FE simulations agree well with the experimental dat of displacement, strain and stress for all the range of wedge angles and temperatures examined.

Reinforcing or repairing concrete structures with carbon fiber- sheet (CFS) is a new advanced method to increase load-carrying capacity and extend the life in service. In this paper, a kind of concrete 3-point bending specimens and that reinforced by CFS are used to experimentally study the fracture mechanism and the extreme load-carrying capacity of the specimens, with several different depths of V-notch, a₀, and different lengths of the carbon fiber sheet, L_x. The experimental and analytical results of the beams adhered with CFS are: 1) the stiffness and strength of the beams are increased; 2) the failure mode is different from that of plain concrete specimen; 3) the load- carrying capacity is increased greatly; 4) the relationships between the extreme load P and the depth of V-notch a₀, and P vs L_x were established.

We present a differential microwave apparatus to investigate the mechanical behavior of samples subjected to any stress which produces a change in the sample length. The device measurements small displacements through the measurement of the resonance frequency variation of a microwave resonator and corresponds to about 7 X 10^-8 in the height of the resonator, having such dimension as to resonant in the TE₀₁₁ mode in the X band. This means that changes in the sample length of some nanometers can be measured, whatever is the value of the sample length. The resolution of the device of some nanometers 'single shot' looks high enough, however the good stability of the apparatus along long periods allows that periodic stresses and averaging may be applied, in this way the resolution becomes some picometers. The extended measurement range is another interesting feature of the apparatus, indeed, if the DC coupling is used, with the resolution limit less than one ten of nanometers, a displacement up to 100 micrometers can be recorded. The frequency response ranges from DC to some Hz.

Localization is an important phenomenon for rock materials when undergoing compressive or tensile load. In this paper, one of the well-developed optical metrology-Digital Speckle Correlation Measurement is used to observe the localization in rock materials. A white light source is used in the experiment, thus the optical setup is very simple. This method is much less constrained for environment and then is suitable to the measurement of rock structure in situ.

Plastic-bonded explosive is a kind of energy material used in military and civil engineering. It serves also as structures or components to sustain external loads. Safety and reliability of the material is of importance to prevent damage and fracture during both manufacturing and usage procedure. Digital image correlation technique was applied to analyze the deformation field of the material near crack tip. The specimen was loaded by uniaxial compression and a slot was preset at the specimen edge with 45 degrees orientation. The speckle images were captured during the load and the surface patterns were matched by correlation computation to obtain the displacement components. The stress intensity factors of the crack tip were evaluated by the deformation in the near region of the crack. By the comparison of the strain field and the surface profile, the damage form of the material can be analyzed that showed brittle behavior with axial splitting fracture.

Affixing high strength fiber-sheet is an advanced method to reinforce or repair the concrete structures. In this paper, the theoretical analysis and FEM are used to discuss the effects of carbon fiber-sheet (CFS) on the stress field of the reinforced concrete 3-point bending specimens with V-notch. The results show that affixing CFS to the bottom of the specimen can change the stress distribution and failure mode of the specimen. The failure mode of CFS reinforced concrete specimen is determined by the location and size of the 'over-stress area' on the concrete side of the interface between concrete member and CFS. Moreover, the location and size of the 'over-stress area' is affected greatly by the length, L, of the CFS. Therefore, to improve the load- carrying capacity of the specimen, the 'over-stress area' on the concrete side of the interface should be within the affixing length of CFS. The length of the CFS should satisfy the requirement: L/S >= 3/4.

This paper is concerned with the transformation plasticity of a 16MND5 low carbon steel. We present an experimental set-up to perform thermo-mechanical loads under tension-compression- torsion. Some results in the case of constant and non constant applied stresses are shown.

A non-contact measurement technique of Rayleigh wave velocity is proposed. In the non-contact measurement system, a laser Doppler velocimeter is used to determine wave motions. With above technique, the relationship between Rayleigh wave velocity and stress for an aluminum alloy 5052 and steel SS400 is determined, and the results are in good agreement with that obtained by contact measurement method.

A digital speckle micro-metrology system, which is a combination of a long-focus microscope and a digital image-measuring device, is developed for studying the micro-mechanics behavior of the interphase in thermoplastic composites. In this paper, the micro- metrology system is employed to obtain the displacement field in each step, strain field in the area across the interphase and to investigate the effect of temperature on the interphase micro- mechanics behaviors of thermoplastic composites. The experimental results show that a significant mismatch of properties across the investigate the effect of temperature on the interphase micro- mechanics behaviors of thermoplastic composites. The experimental results show that a significant mismatch of properties across the interphase are compensated under practical service conditions of 100 degrees C.

2D diffraction systems, when used for residual stress measurement, have many advantages over the conventional 1D diffraction systems in dealing with highly textured materials, large grain size, small sample area, and weak diffraction systems in dealing with highly textured materials, large grain size, small sample area, and weak diffraction. The stress measurement is based on the fundamental relationship between the stress tensor and the diffraction cone distortion. The benefit of the 2D method is that all the data points on diffraction rings are used to calculate stresses so as to get better measurement result with less data collection time. The present paper introduces the recent development in the theory and applications of stress measurement using 2D detectors.

Piezoelectric thin films with x equals 0.58 were deposited on Pt/Ti/Si by pulsed laser deposition (PLD). In the paper, the indentation fracture method was first used to determine the residual stress and fracture toughness of PZT thin film. In the determination of residual stress by indentation fracture method, two models including GLFW model and ZCF model were adopted. The fracture pattern diagram as a function of indentation load and thin film thickness was introduced. Radial and lateral cracks were observed in indentation with a Vickers diamond indenter. The experimental results show that the residual stress values measured by ZCF model were closer to the results measured by x- ray diffraction and the interface fracture toughness was much lower than the surface fracture toughness of PZT thin film.

The fully 3D orthotropic elastic-plastic analysis of interlaminar stresses and deformation for AS4/PEEK thermoplastic laminates is developed in this paper, and used to simulate the tensile stress- strain curves for (+/- 25)_s4 laminates. Under uniaxial tensile loading, the 3D orthotropic elastic-plastic FE analysis and microscopic moire interferometry of interlaminar stresses and deformation are carried out for the (+/- 25)_s4 laminates. It is found that the numerical tensile stress-strain curves of (+/- 25)_s4 laminates agree with experimental. The numerical interlaminar displacement u and shear strain (gamma) _xz are also consistent with the experimental results obtained by moire interferometry.

The Interferometric Strain/Slope Rosette (ISSR) is combined with ring-core method to measure residual stresses. The method has many advantages such as non-contacting and short gage-length compared with resistance strain rosette/ring-core method. The ISSR measures the relived strains during ring-core cutting. A finite element model is set up to calculate residual stresses. Two experiments are conducted on an aluminum plate to determine the residual stresses induced form its manufacturing processes. The residual stress distributions with depth are measured by using incremental ring-core cutting around an ISSR.

A test system of fiber optic displacement sensor (FODS) was developed and applied to measure Ag clad multi-core (formula available in paper) (Bi2223/Ag) superconductor tape at liquid nitrogen temperature (77K). A method intensity compensation was used to eliminate the fluctuation in light source and fiber attenuation. The sensor's transmission characteristics and calibration function were obtained at 77K. The stress-strain curve of the multi-core Bi2223/Ag tape was presented, and its stress-J_c relationship provided a useful reference to the application of the tape. The obtained result reveal that: (1) this sensor system can normally work at 77K; (2) its linear operating range is up to 1.6mm; (3) multi-core Bi2223/Ag tape's stress-stain relationship and stress-J_c relationship can be measured real time; and (4) it overcomes the weaknesses that cryogenic strain gauges can only measure the surface deformation of these kinds of composite tapes.

Silicon die and copper leadframe in IC packaging are bonded by die attach adhesive, and the quality of the interface is a critical issue in the reliability testing of IC packaging and during the manufacturing process. Common defects such as crack and delamination can be detected using C-mode scanning acoustic microscopy. However, weak interface due to poor adhesion has often gone undetected and may become potential defective area at a later stage. This paper describes the work in evaluating the quality of the weak interface between die attach and copper leadframe. An interface spring model is used to predict the ultrasonic reflection coefficients. Normal incidence reflection coefficients are measured from the two-layered specimen bonded with die attach adhesive. Varying copper oxidation is used to simulate the degrading of the interface, and effect of shear stress loading is discussed. It is shown that the reflection coefficient depends strongly on the interface quality and stress loading, indicating that the nondestructive characterization of the interface is possible and reflection coefficient can be used as a criterion.

The digital speckle correlation method (DSCM) is a rapidly developing technique of photomechanics. It has been used to measure the surface deformation for its advantages of non- contact, real time, whole field and direct measurement. In this paper, an algorithm is proposed by introducing optimization theory into DSCM. In the improved DSCM, the 1D search determines the step size of iteration, and the inverse matrix of second- order derivative matrix of correlation function is calculated by the quasi-Newton method. By the improvement, the computational; workload is reduced and the convergence velocity is improved. This paper also illustrates the application of digital speckle correlation method in experimental fracture analysis of copper film. Experimental results show that the improved DSCM is an efficacious test techniques in studying the fracture behavior of thin film materials.

This paper mainly introduces the method of automatic monitoring and measuring applied in the construction of Taiyuan Underpass Bridge and the component of hardware and software of this system. It is a good method to automatically monitor and measure the construction of bridge, tunnel and underground works.

Supervising and health monitoring of engineering structures presupposes application of experimental mechanics methods. They have to yield the data-base, i.e. the state of displacement and strain respectively to control the design data and to determine the internal parameters like the stress-state, the structural response, the reliability, safety and probable service-life. To obtain these finally wanted information the measured quantities are to evaluate. This leads to inverse problems, the solution of which requires proper mathematical/numerical methods. With concern to truss- and frame-works as well as to plane- and shell- structures some algorithms will be presented, which have been proven by a few examples.

In this paper, three loading control methods of structural seismic test along with software developments and applications are introduced: (1) quasi-static test method and control software TUST; (2) multi-dimensional quasi-static test method and control software TUMT; (3) pseudodynamic test method and control software TUT, 2D and substructuring techniques. The alpha-method and PC- Newmark method were employed in TUT. All of the three tests loading control software that is based on the platform of Windows NT and Visual C++ have been put into practice in structural laboratory of Tsinghua University.

With the rise in collision accident and the increase in requirement for resistance of blastproof structures in recent years, people attach much importance to the research and application of energy-absorbing device. In this paper the author calculates the specific strength, the specific hardness and ultimate internal force of a circular thin-walled tube by theoretic calculations, discusses the feasibility of using circular thin-walled tube as an energy-absorbing element, analyzes the energy-absorbing properties and the energy-absorbing mechanism through the energy-absorbing experiments using various materials and forms of arrangement, reaches the conclusion that the load-bearing capacity and energy-absorbing properties of multilayered tubes are superior to that of single tube, and puts forward the concept of 'grading tube'.

The digital photoelastic and finite element methods were combined to clarify the interfacial stresses predicted by Suhir's theories. A special casting procedure was employed to obtain a true bi-material structures such that the theoretical assumptions can be satisfied. Through the analysis, some behaviors of the interfacial stresses were clarified. Besides, the distributions of the thermal stresses in the adherends calculated by Suhir and Timoshenko's theories were also discussed.

A new method using cameras as transducers to measure the bridge displacement and vibration is developed. The method and corresponding system have the advantages of non-contact, high accuracy. Also it can dynamically measure the displacement and then derive the vibration parameters of the bridge. The accuracy of the optical measurement system can reach to 0.017mm.

Under the run operating condition, the effect of high temperature will exist in buckling behavior of FBR main vessel. In this paper, we carry out the experimental analysis of the main vessel with inter heat source; give some important results, and analysis the influence on buckling strength caused by repeated instability accumulative damage, hydraulic pressure and thermal loads. Prove buckling strength reducing due to the reduction of material properties with temperature. The experimental buckling loads agree with the calculated results very well and the reliability of numerical simulation was validated. The buckling mode is studied by photomechanical measurement, in which moire is employed. The experiment provides modelization and value mode for modeling of numerical calculation.

The low strain reflection wave method plays a principal rule in the integrating detection of base piles. However, there are some deficiencies with this method. For example, there is a blind area of detection on top of the tested pile; it is difficult to recognize the defects at deep-seated parts of the pile; there is still the planar of 3D domino effect, etc. It is very difficult to solve these problems only with the single-transducer pile integrity testing system. A new multi-signal piles integrity testing system is proposed in this paper, which is able to impulse and collect signals on multiple points on top of the pile. By using the multiple superposition data processing method, the detecting system can effectively restrain the interference and elevate the precision and SNR of pile integrity testing. The system can also be applied to the evaluation of engineering structure health.

The welded lap joints with different matching are analyzed by Moire interferometry. The strain distribution with lower matching in front weld metal are higher than that with higher matching in front weld metal. The strain distributions with lower matching in base metal are lower than that with higher matching in base metal. The strain distribution of different matching along the force parallel direction has little difference. The V field fringe deformation of different matching in base metal and weld metal are the same. The U field fringe deformations are different. The fringes with lower matching in weld metal are more crowded than base metal. The fringe with higher matching is more concentrated in the middle. The strain distributions of higher matching in weld metal are lower. The finite element was used to prove the experiment results in this paper. This result has engineering meaning to improve the mechanical properties of the welded lap joint.

The present paper proposed a hybrid method to obtain whole-field thermal stresses in reinforced concrete building structure. The temperature gradient of structure due to environment temperature change is measured by the specially sensor which buried inside the concrete components, and the thermal stresses are analyzed with finite element method. An example of a building with 32- stories was presented.

Thermoelastic stress analysis is used to obtain the stress concentration factors from a variety of circular holes in cylinders. The cylinders are loaded in uniaxial tension, uniaxial compression and a combination of bending and compression. Firstly, radial holes are investigated and the results from the thermoelastic data obtained by the SPATE equipment are compared to previous experimental and numerical work. SCFs are then obtained form offset, oblique and offset-oblique holes using the Deltatherm system. The effect of hole obliquity and direction of applied load relative to the hole geometry is discussed.

This paper reported x-ray residual stress measurements of a large spherical vessel with cracks. The first measurement was taken for defect analysis, and the second and third were taken for evaluating the effect of local heat treatment on reducing residual stresses. Furthermore, in order to evaluate further run of the vessel, applied stresses were obtained using strain gauge during hydraulic test.

A full-driving barge refitted by a 2000t deck barge would be used for salvaging at the sea of which the planned diving depth will reach to 14 m. The hull structure would suffer form different but complicated loads because of the refitting and actual diving process, and the structure should be analyzed and approved by calculations and experiments. The test was carried out at the site of Santou bay. A multi-channel static-dynamic strain test system was adopted to survey the main components of the hull structure under load cases. The hydraulic pressure was mainly considered and divided into different classes in diving process. The readings of strain gauges in different components were processed by a computer linking to the test system. It was shown that the results were coinciding with the calculated results. And it is concluded that the refitted full-diving barge hull is safe at the designed depth.

This paper introduces how to in situ observe fracture behavior around crack tip in ferroelectric ceramics under combined electromechanical loading by use of a moire interferometry technique. The deformation field induced by electric field concentration near crack tip in three-points bending experiments was measured. By analyzing the moire interferometry images it is found that strain decreases faster than values predicted by the theoretical analysis as the distance away from the crack tip increases.

Failures of turbine blades are identified as the leading causes of unplanned outages for steam turbine. Accidents of low-pressure turbine blade occupied more than 70 percent in turbine components. Therefore, the prevention of failures for low pressure turbine blades is certainly needed. The procedure is illustrated by the case study. This procedure is used to guide, and support the plant manager's decisions to avoid a costly, unplanned outage. In this study, we are trying to find factors of failures in LP turbine blade and to make three steps to approach the solution of blade failure. First step is to measure natural frequency in mockup test and to compare it with nozzle passing frequency. Second step is to use FEM and to calculate the natural frequencies of 7 blades and 10 blades per group in BLADE code. Third step is to find natural frequencies of grouped blade off the nozzle passing frequency.

To characterize the S-N curve form in gigacycle fatigue, five high strength low alloy steels with tensile strengths from 1500 MPa to 1800MPa were tested at very high numbers of cycles through piezoelectric fatigue test at 20 KHz. A significant change in the slope of S-N curve was observed, accompanying the transition form surface to subsurface crack initiation. The S-N diagram on these steels reveals a two-stepwise shape, and the S-N curve tends to drop down again after 10⁷ or 10⁸ cycles. The specimens continue to fail over 10⁷ stress cycles. It should be significant to realize the risk of obtaining the fatigue limit at 10⁷ cycles.

This paper proves that the damage factor of rocks can be described as equation (1) by uniaxial compression, and the Kaiser effect of acoustic emission has very good ability to remember its previous damage factor.

In this study, fatigue crack growth (FCG) behavior of pre-cracked Al 7075/T6 substrates with bonded composite patches is investigated experimentally and analytically. Boron/epoxy patches with 2-, 4- and 6-ply are installed on Al substrates with single- side crack. Tension-tension fatigue test are also conducted on Al substrates to establish their fatigue behavior for comparing with the repaired specimens. A considerable increase in the fatigue life and a decrease in the stress intensity factor are observed as the number of plies increased. An analytical mode, based on Rose's analytical solution and Paris' power law, is developed to predict the FCG behavior of the repaired substrates. The analytical and experimental results are in good agreement.

IN this paper, a system of micromechanical experiments is established combining microscopic moire interferometry of high spatial resolution with optical microscope. Under uniaxial tensile loading, the quantitative local-field of interlaminar displacements of the AS4/PEEK laminates has been measured. The pictures of in-situ interlaminar damage initiation and growth process have been simultaneously collected by the experimental system continuously. The major characteristic of interlaminar damage of the laminate under tensile loading is the group of matrix cracks in 90/90 plies, which are formed due to fiber- matrix interface debondings, and the number of cracks increases when the load increases. The u fields of interlaminar displacement of a matrix crack under certain loads are gained using the microscopic moire interferometry.

In this paper, the wavelet transform is applied to the time- frequency analysis of the flexural waves in beams for crack detection. Here, a cantilever beam with edge cracks is used for a model to analyze the wave information after it is loaded an impact hammer on its free end. The flexural waves propagating in beams are dispersive and can be measured directly by using electrical-resistance strain gauges during the dynamic process. According to the data about one-crack and two-crack beams, we utilize the Morlet wavelet transform to decompose the flexural waves into each frequency component in time domain. The experimental results illustrate that the crack position can be detected exactly by means of the signal of mid-frequency flexural wave extracted by wavelet transform. The method is also suitable for determining the existence and location of multi-crack in a beam.

In this paper, moire interferometry and finite element analysis (FEA) have been applied to study interface fracture behaviors of Porcelain-fused-to-metal (PFM) restoration. The fracture criterion of an interface crack between the porcelain and metal is based on the maximum stress. The influence of the thickness ratio, load value and load form on the predicted kinking angles has been proposed and discussed. It is shown that the predicted kinking angle does not varied with load value. The magnitude of crack-kinking angle is more sensitive to load from than to thickness ratio. Measured data accord well with numerical value. These results provide data for the optimized design of clinical PFM restoration and for understanding fracture mechanism of the restoration.

Experiments for damage evolution of internal structure in Bi- 2223/Ag sheathed tape under tensile loading at 77K were done at BSRF. With increasing of load, the start-up and growth of micro cracks in tape were observed. Depending on the experimental results, it showed that: superconducting capability kept on when the material was at linear elasticity, and would lose when the material came into being plastic flow.

The influence of thickness and mixed mode I/II loading on the crack initial angle of aluminum LC4-CS plates of 2, 4, 8 and 14 mm thickness was investigated experimentally from tensile-tearing testing of the compact-tension-shear type specimens. Experimental results of the crack initial angle for various thickness plates and load mode mixity were presented, and compared with theoretical predictions form the maximum tangential stress criterion and the maximum triaxial stress criterion. The crack initial angle is found to vary not only with load mode mixity but also with specimen thickness. The experimental result show a god agreement with theoretical predictions in 2, 14 mm- thickness specimens but a great deal difference in 8 mm-thickness specimens. The results are discussed in the viewpoint of 3D failure theory.

The performance of mechanical parts is influenced by residual stresses. Because of the randomness of residual stresses, they are very difficult to be determined by theory. The present treatment emphasizes methods for measuring residual stresses, and there are many methods for it. In this paper, one kind of three directional grating is made by the author, here denominating it as 'grating rosette', and by means of the moire interference technique and hole-drilling, a new method of residual stress measurement is developed.

Dynamic fracture process of the woven cloth reinforced composites under tensile load is studied by multi-spark high-speed photography with reflective arrangement. Crack trajectory at different instant is shown by the specimen-focused images. Some important fracture characteristics such as crack tip position; crack length and critical load are determined, and microscopic fracture mechanisms of woven composites are analyzed by SEM.

Fracture behavior of an ultra thin Aluminium foil was studied. For very short crack lengths, fracture has been followed in the scanner electronic microscope (SEM) with a tensile stage. A single edge notched tension specimen was used. Crack length and applied load during the crack growth were measured. These results have been used to calculate fracture strength using linear elastic fracture mechanics and a strip yield model. The results are discussed in general and in particular regarding the importance of process region modeling.

Heating by an electromagnetic field is an effective method for stopping internal crack propagation in metal components, thus extending their service life by improving safety and reliability. Experimental surveys show that a small spherical crater can be formed near the crack tip using a concentrated current which melts metal at the desired point. Experiments also show that the sharp point around the crack tip is rounded, which decreases the stress concentration and forms a compressive stress area. These structure around the crack tip is refined obviously. At the same time, a white-bright layer is formed around the crack tip under the influence of a precipitous temperature gradient. Thermal compression stresses and phase transformation stresses, together with the influence of a super-fine microstructure, promote the ability of metals to withstand intense wear. From the experiments we also find many factors have an effect on the efficiency of crack arresting.

Systematic experimental studies of rocks under cyclic loading with lower and higher frequency at the pre- and post-peak were conducted in present paper. The macro fracture of samples, strength property, different deformation development of average strain and strain in the middle of sample, the plastic detained loops, and the development of tangent modulus during cyclic loading were analyzed in details to show the structural property of rocks.

A new automatic measurement technique for 360 degrees surface topography of 3D diffuse objects is proposed in this paper. The technique bases on a new structured illumination method, called step projection, and a new algorithm. The principle, hardware and software of the automated measurement system are completely expressed. Some researchers are carried out on the accuracy of step projection. It is suitable for 360 degrees objects like asymmetrical cylinder, especially for objects with irregular surface. Besides this, it has many advantages, such as simple optical setting, lower cost, and easy determination of deformed line's position. Using the technique a 360 degrees 3D object with greater grads change on its surface can be reconstructed. The shape of flow passage of engine valve is very irregular. By using the automated rotation profilometry, it can be measured accurately. The experimental results are offered.

A well-founded and computationally fast method is presented for filtering and interpolating noisy and discontinuous wrapped phase fields that preserves both the 2(pi) discontinuities that come from the wrapping effect and the true discontinuities that may be present. It also permits the incorporation of an associated quality map, if it is available, in a natural way. Examples of its application to the computation recovery of discontinuities phase fields from speckle interferometry fracture measuring are presented.

This paper presents an endoscopic digital holographic interferometry system which is based on phase-shifting in-line digital holography. The system is able to measure both the shape and deformation of an object with the advantages of digital holography, such as real-time processing of the hologram. Two theoretical problems are briefly described: phase-shifting in- line holography and hologram data re-sampling for 2-wavelength contouring. In addition, initial experimental results of the deformation of a metal piece and surface 3D-shape measurement of a bottle cap are given.

In three-dimensional projecting grating profilometry, we are often persecuted by some disgusted phenomenon of images, such as reflecting flare, overlapping of grating and other noises. All these can bring a bigger error in image processing. The intention of this paper is to propose some new methods of image processing. The technique we applied is based on frequency domain digital image processing, morphology method and partial handling method. As the background disturbance can be eliminated by frequency domain filter, many image noises can be suppressed and the distinguishing feature of grating can be accentuated by morphology method with suitable structure element and partial handling method. Thereby, the result of the surface shape can be calculated much better than the conventional method. The results of experiment indicate that new methods have remarkable effects.

By modifying the hardware of a heterodyne moire interferometer (HMI) the measurement range, accuracy and efficiency of the new system can be improved significantly. With this new system, whole-field measurement of displacements and strains can be achieved by translating the photodetectors. Test results have demonstrated that this new HMI system is potentially a good alternative tool for micro-metrology.

It is possible to measure the 3D shape of an object using grid projection methods. Moire topography which is a kind of grid projection methods can obtain the contour lines of the measured object in real-time. The authors developed a real-time shape measurement system based on the Moire topography. In order to perform quantitative and real-time shape measurement, we developed the integrated phase shifting method. However, the obtained distribution is wrapped in the range of -(pi) to (pi) . Therefore, a real-time phase unwrapping process is required. The present paper proposes a new unwrapping method using a composite rectangular grid which si composed of two rectangular waves of different pitches. The composite rectangular grid is projected onto an object. Each phase distribution of the two waves can be separated and calculated using the integrated phase-shifting method. The unwrapped phase distribution is produced from the two different phase distributions.

Some study results on photoelastic coating technique is presented in this paper. The study results include the manufacture method of photoelastic coating; the confection of adhesive, the design and integration of both the on site measure device and measure system with changeable wave length, as well as the system of data collection and process. The study results have been applied to practice test of the parts of mechanical products, for example, the integral structure analysis of the W67Y-63 sheet bend machine, the measure of residual stress due to welding of different steel.

In this study, a new experimental system, which integrated Holographic Interferometry (HI) with Moire Interferometry (MI), was developed for thermal deformation measurement in a ball grad array (BGA) assembly caused by power cycles. In the experiments MI was used for the in-plane measurement, and HI was used for the out-of-plane measurement, and furthermore, MI and HI were simultaneously operated. Therefore, it provided whole-field displacement information including the in-plane and the out-of- plane deformations with high sensitivity and resolution. The results showed that the in-plane expansion of the PCB was larger than that on the CBGA, and the PCB and the CBGA bended with different curvature. The corners of the CBGA were high strain concentration areas. The crucial techniques for thermal deformation measurement using the HI/HI system and typical experimental results for the CBGA-PCB assembly are described, and also, the reliability of solder balls of CBGA is discussed based on the measurements of the in-plane and the out-of-plane deformations.

In measurement of 3D object shapes using projected grating method in situ, the calibration of parameters is one of the most important factors that affect the measurement accuracy. In this paper, a study is conducted on the technique of calibrating parameters in 3D topography measurement and the Fourier phase demodulation technique is used to process the experimental data. Eth calibrations of the coordinate system and geometry parameters are provided. Some experimental results are given and the measurement sensitivity and accuracy are discussed.

A non-contact and non-destructive method for full-field in-plane strain measurements has been developed. Digital image processing is employed for monitoring the deformations of gird liens marked ona planar surface of a component or a specimen. Full-field in- plane strain distributions are obtained by processing the geometrical characteristics of the grid with computer graphics algorithms. The applications and the future evolution of this method are discussed.

This paper presents an improved automated grid method using loop encoding technique which can be used to measure deformation of large specimen with cavity in situation. The method represents an extension of the applied field of automated grid method. New software for grid auto process and analysis based on the improved method is developed. Computer simulations are conducted and validated against the experiments. The accuracy of the method is also discussed.

In this paper, we present an ESSPI-based method for non- destructive testing of laminated composite using wide audio- frequency driving vibration. This method is simple to operate and has many advantages over other NDT techniques.

In the paper a new birefringent phase shift method is presented, which can distinct the isodyne images by the carrier fringes related with the material uniform initial birefringence. The theory and the technique of the new method are described. The computer generated isodyne images with carrier fringes are applied to explain the method.

The surface of metal structure can be transmitted into nanocrystalline by means of supersonic shot-peening. Residual stresses of stainless steel 316L caused by surface nanocrystalline were studied by a combined method of moire interferometry and hole-drilling. Residual stresses of different specimens with nanocrystalline layer and plastic deformation layer removed were also studied. The experimental result show that nanocrystalline layer and plastic deformation layer are main parts to remain high residual stresses, and to enhance the mechanic behavior of materials.

A method based on birefringence principle of micro-region stress measurement is presented in this article. Frequency analysis of Fourier transform is used in data processing. This measurement system has the merits of high sensitivity and automatic data processing.

A new approach for whole-field digital determination of isoclinic angle and total isochromatic fringe order is presented. The method uses a plan polariscope with two different filters to calculate the photoelastic parameters, and to compensate the influence of the isochromatic fringes on the isoclinic pattern. The method allows for the determination of whole-field fringe orders without zero-order fringes.

Steel structure roof may be damaged during transportation or assembly, after damaged it must be repaired in site to meet the needs of the engineering quality and use. This paper describes the damage of No. 2 steel structure storehouse in Yantian Harbor in the process of assembly due to typhoon, which results in different damage on the steel structure roof. The repairing technique and inspecting method and criteria to ensure the strength, stiffness and local stability of the structure are also discussed. The result shows that the repairing method is successful.

In this paper, a novel approach for fingerprint identification has been proposed in which a frequency coding can be performed for fingerprint classification. The feature of orientation is extracted by spectrum analysis in frequency domain. There are proposed classification and identification by digital FFT method.

A novel fringe processing method is proposed to segment whole- field strain distributions by incorporating moire interferometric technique. By applying an elaborately designed filter bank, the proposed scheme is employed to measure fringe frequency and hence determine derivatives of displacement.

Shearography is a very powerful optical technique for both stress analysis and nondestructive testing (NDT) of composite. Sensitivity of the method is somewhat confused. The method has maximum sensitivity as high as holography. The sensitivity is approximately proportional to shear distance when the shear distance is relatively small. How does the sensitivity change from zero to maximum. It is a useful discussion for NDT applications because the size of defects is not very big compared with shear distance. In this paper, the interpretation method for Shearography was studied first. A new method to interpret shearogram, so called 'difference of twin points' displacement', was presented. The method doesn't use the assumption of small shear distance and can be used for sensitivity analysis art any shear distance. A mechanical model of the defect was built to analyze the sensitivity of shearography in NDT. The quantitative relationship between sensitivity of shearography and the shear distance was given after mathematical analysis. Error of classical interpretation was analyzed.

In this paper a newly developed 3D surface shape measuring system together with its application to the metrology of surface form of blade. The experiment shows that 3D500 measuring system is a useful tool for surface evaluation with character of full-field, on-line, real-time measurement that are important to the quality control inspection of the profile of turbine blade.

This paper described principle of some projection technologies, attached importance to some measurement technologies in engineering and measurement in complicated profile of fine-micro body. The optoelectronical system and the image processing system are supplied. The typical measurement result are obtained. It is proven that the projection technology is a composite technology, which has extensive applications in many ways.

Based on image and graphic technologies and synthesized preceding research achievements in the digital processing of photoelastic image, a vectorization system for interactive photoelastic image processing has been set up. The system consists of seven modules, and a toolbox. This paper describes the system structure, new techniques used in the system, and its features. By use of this system, the vectorized image files of the skeleton for stress analysis can be obtained. The application area of the system is wide, and it has quite strong interactive processing capability and user-friendly interface.

Filtering off noise form fringe patterns is important for processing and analysis of interferometric fringe patterns. Spin filtering proposed by the author has been proven to be effective in filtering off noise without blurring and distortion to the fringe patterns with small fringe curvature. But spin filters still have problems for the fringe patterns with large fringe curvature. In this paper we develop a new spin filtering with curve windows to be suitable for all kinds of fringe patterns regardless of fringe curvature. The curve windows in the filtering coincide with the local fringe contours of fringe gray levels. The experimental result show that the new spin filtering provides the optimal results in both filtering off noise and remaining fringe feature.

Grating projection methods have been often used for non- contacting shape measurement. An image of equal-height contours of an object can be obtained in real-time using moire topography. We have developed the phase-shifting scanning moire method for real-time shape measurement with high resolution. But there is a problem that the measuring error becomes larger when the object is moving speedily because several images are captured while shifting the grating phase. In this paper, we propose a phase- shifting scanning moire method using a DMD, which can obtain an image of equal-height contours within a frame time. The direction of a ray reflected at each mirror of a DMD can be selected quickly. For this purpose, we developed a DMD reflection-type CCD camera called as 'DMD camera'. The camera works as a camera whose each pixel has a shutter. The structure and an experimental result to confirm the algorithm to obtain a contour image using het DMD camera are shown.

High magnifying optics is now widely used in micro-region imaging, which leads to the special image structures on the recording plane, such as continue-gray distributions, large granules and spread structures. As a result, the deformation analyses are unreliable and divergent by using the conventional speckle correlation methods and these generalized speckle patterns. A new correlation algorithm, high-order gradient digital correlation method, has been proposed in this paper to measure the displacements in a micro-region. The performance of the proposed algorithm is illustrated using the generalized speckle patterns captured from the micro-regions.

In this paper, an advanced image processing method, the discrete dyadic wavelet transform based non-linear filtering method applied to speckle fringe pattern, is presented. By this method, an image can be expanded to a series of sub-images according to their frequency band. The different filtering skills will be applied to the sub-images and the rebuilt image will keep the original characteristic except the speckle noise. For example, it can keep the border of the object in the fringe pattern clearly after filtering the speckle noise. Compare with the other kind of wavelet transforms, the Discrete Dyadic Wavelet Transform need not decreasing sample the original image, so the distortion of the rebuilt image can be greatly avoided. The principle of the dyadic discrete wavelet transform is introduced first, and then a practical algorithm to reduce the speckle noise of a fringe pattern is given. At last part of this paper, a computer simulation result processed by this method is presented.

A new phase unwrapping algorithm is proposed in this paper. This algorithm, based on the global continuity of the physical information being measured, is shown to be reliable by experimental results. Unlike the brunch-cut method, this new algorithm needs not placing brunch cuts but ratifying the errors in the initial unwrapped phase map obtained by the conventional method using the least difference of phase-cross-section. It is suitable for unwrapping phase map in the presence of errors such as noise, phase discontinuity more than (pi) and insufficient sampling. In addition, the new method is simple and requires little computing time.

In this paper, a new digital-image correlation method-twelve variables gradient method is presented. The influence of second derivative terms of displacement is considered, the directional derivatives of correlation coefficient are obtained and variational step-length search is used in this method. Consequently, the truncation error caused by increasing of subset size and vast computation time are avoided. The measurement precision of displacement and strain are less than 0.011 pixels and 100 (mu) (epsilon) , respectively. Two test experiments and the application show that this is an efficient and accurate method.

In this paper, the four-step phase shift method is applied to obtain the initial stress components in an unloaded square plate made of epoxy resin. The computer analogy images with random noise are used to study the sensitivity and reliability of four step birefringent shift method in the low signal condition. The computer experiment shows that the reliable result could be obtained even the phase is less than 1/8 fringe order with laser noise.

Presented in this paper is the development of a fractal interpolation method and the fractal iterative function system method for calculating subpixels in digital speckle correlation. As an illustration, the displacement of an object under rigid- body motion is determined using ht methods described.

The traditional theory about the digital-image correlation method (DICM) is modified, and a nonlinear displacement model is proposed and developed. On the basis of the displacement mode, both the Jacobian Vector and the Hessian matrix of the Newton- Raphson iterative method for estimating the approximate values of displacements and their gradients are given. The computer software for the nonlinear DICM is developed. In this paper, a rubber specimen stretched is employed, and the strain components at an arbitrary point of interest are computed using the nonlinear DICM. The experimental results show that the research work lays foundations for improving the accuracy of measuring finite deformation using DICM.

Ballistite and polymer materials are one kind of special composite material possessing the special properties of large deformations under loading. Because they have wide applications in aerospace industry and strong effects on the reliability and stability of the aerostats, experimental measuring the mechanical behaviors of these materials is highly emphasized. However, due to their special properties of the large and time-dependent deformations under loading, it is hard to use conventional optical methods to analyze their mechanical behavior. In this paper, two methods, scanning phase method (SPM) and time sequence phase method, have been used to large and time-dependent deformation analysis for ballistite and polymer materials. The deformation and creep behavior of the ballistite material is experimentally measured and analyzed under thermal loading and mechanical loading. Meanwhile, the large deformation of the polymer material is also measured under mechanical loading. The experiment results including the material parameters, the deformation and the creep curves are presented. The applicability and performance of these two methods are also discussed.

Fringe orientation is important information for processing and analysis of interferometry fringe patterns. It is useful to estimate fringe orientation. However when the signal to noise ratio of speckle pattern is unity, it is difficult to extract signal from single speckle pattern. In this paper, an adaptive algorithm for estimating fringe orientation of speckle patterns is proposed. This algorithm includes three steps: computing the local fringe width in a low precision, estimating fringe orientation with curved surface fitting and smoothing fringe orientation map. The experimental result show that this algorithm is efficient for speckle interferometry fringe patterns. Of course, this algorithm is suitable to the others of interferometry, such as conventional holographic and moire techniques.

A new digital speckle correlation method, the Wavelet Transform based DSCM (WTDSCM) is presented. By this method, the two images of an object before and after loading can be expanded into two series of sub-images according to their frequency band respectively by wavelet transform. Choosing the suitable sub- images pairs mainly contributed by signal speckles, and then inducing the DSCM to calculate the deformation of the object, the probability of mismatch caused by noise could be reduced and the precision of DSCM can be improved. The experimental calibration results indicate that the precision of the WTDSCM is higher than normal DSCM.

Because some composite material, thin film material, and biomaterial, are very thin and some of them are flexible, the classical methods for measuring their Young's moduli, by mounting extensometers on specimens, are not available. A bi-image method based on image correlation for measuring Young's moduli is developed in this paper. The measuring precision achieved is one order enhanced with general digital image correlation or called single image method. By this way, the Young's modulus of a SS301 stainless steel thin tape, with thickness 0.067mm, is measured, and the moduli of polyester fiber films, a kind of flexible sheet with thickness 0.25 mm, are also measured.

Path independent algorithm is frequently used for 2D phase unwrapping. The weighted phase unwrapping technique recently published by Ghiglia and Romero, which is based on least-squares method, obtained by the fast cosine transform, is a robust and fast path independent solution. We have improved weighted phase unwrapping by utilizing intensity modulation analysis to determine the weights for phase-shifting profilometry. An experimental result of object shape measurement is given to prove the validity of this technique, and make a contrast between the binary weight and decimal weight constructed by modulation analysis.

Solder joints between a ceramic ball grid array (CBGA) and a printed circuit board (PCB) generally suffer important thermal strains and stresses during the operation of devices as well as under temperature variations. Mainly, these tend to increase the thermal stress concentration in solder joints. In this study, moire interferometry is used to measure the power-induced thermal displacement in the CBGA assembly. The experimental study is performed under various environmental temperatures using different power levels. Two types of thermal strain distributions are found in the assembly, depending on the thermal loadings. The stress concentrations are located in the CBGA assembly. Then, based on the relative displacement between the CBGA and the PCB, the shear stress on the solder ball is determined. Moreover, the effects of different thermal loadings on the CBGA as well as their impact on the reliability of CBGA solder balls are discussed in details.

The reliability and lifetime of microelectromechanical systems (MEMS) are strongly depending on the material properties. It is important to develop methods for the measurement of MEMS material properties. In this paper an optical technique for measuring tensile strain of micro-specimen is proposed. The technique, which is based on digital speckle correlation method works by determining the deformation of specimen between two neighboring loading step by step. The problem of non-correlation is solved when the deformation is too large. The experimental results of a copper wire are given in this paper. The proposed technique is also applicable for measuring other MEMS materials that may be even smaller or thinner than that used in this paper.

Oscillation behavior of two microstructures of MEMS is analyzed in this paper. That is associated with dynamic response of a lateral-vibratory comb-structure in micro gyroscope, and resonance oscillation of a micro-plate with residual stress resulting from film deposition in bulk silicon fabrication. The comb-based micro-gyroscope was fabricated in polysilicon substrate and driven by oscillating voltage. Based on dynamic equations of the microsystem, the responses of the system output are analyzed with different inputs and quality factors. Due to the difference of thermal expansion coefficients of the substrate and the films, residual stresses are normally generated in the layer deposition processing of MEMS fabrication that will affect the performance of the micro-devices. The relation between the residual stress and the membrane's first-modal frequency is presented for a rectangular layered-plate fixed at edges. When the silicon-substrate micro-plate with a single film is actuated by oscillation, the resonance-frequency can be measured so that the in-plane residual stress can be solved. The FEM simulation is also made whose result shows good agreement by the error less than 7 percent.

In this paper, an integrated 3D moire system is introduced and the complex thermo-mechanical behavior of plastic packages is revealed with this system. Testing results show the thermo- mechanical behavior of plastic packages is time dependent, thermal experience dependant and moisture sensitive. The introduced 3D Moire system and testing result provide a basis for further investigation on this problem, e.g. it can provide boundary condition or result confirmation for the FEM investigation.

In this paper, the mechanical-electronic behavior of a bulk- micromachined relay driven by electrostatic actuator for lateral movement, is experimentally studied and simulated. Due to the small size, the deformation measurement of the MEMS relay is very difficult on a macroscopic scale. The digital image correlation technology was employed to determine the dimensions and displacements of the moving relay. Based on the video films and the collapse deformation of the structure, the pull-in voltages were obtained that represent the instability characteristic of the micro-system. Meanwhile, by combining the tools of finite element method and boundary element method, the instability behavior of the MEMS relays was numerically simulated with an electronic-mechanical coupling analysis. The simulation results obtained by this hybrid computation of combining FEM and BEM are in good agreement with the experimental ones.

We report and analyze the oscillation phenomenon on Cu-26Zn-4Al alloy. The experimental observations indicate that the oscillation patterns manifest distinctly pseudo-fluid behavior in localized areas of micrometer order. By using a fluid mechanics approach, we find that the fluctuation of the adatom cell in the surface layer of Cu alloy exhibits the feature of non-propagating surface solitary wave. The exponential decay of the amplitude with time is in agreement with the measurement. It suggests that this new atom-configuration on the surface of solid materials be of some universality.

This paper presents a method, which is based on the Digital-image Correlation Method, for measuring the surface dynamic displacement field of objects under dynamic loading. A high-speed camera is used to record the deformed digital images of the specimen surface under dynamic excitation. By extracting two images at random intervals and use a computer algorithm, the dynamic displacement field of the object surface can be acquired accurately; the precision is in the order of microns.

The interference to the public due to the operations of transit system is one of the major issues to the people in the surrounding areas. The interference is due to the vibrations caused by the rolling stock itself and the interaction between train and the rail. The interaction is propagated by the soil. The soil accepts the energy and produces compressive waves. The waves transmit the energy to the surrounding buildings. The human percepts the vibrations and feels uncomfortable. In order to suppress the vibrations and reduce the noise from the operations of the trains, a suitable mathematical model must set up to begin the analysis of the dynamic characteristics of the rail and the transmission of the vibration. This study is to apply modal testing to measure the dynamic characteristics of the rail to establish a feasible mathematical model. The dynamical characteristics of the rail are obtained by the analysis of the result of a hammer excitation to the rail. The result provide the parameters for the mathematical model. The mathematical model will be more practical and feasible. The final mathematical model will be the foundation to the studies for the interaction of the wheelset and rail and for the studies for the vibrations transmission to the buildings.

A wedge indentation test has been carried out, in which an ultrasonic vibration was superimposed at a frequency of 20 kHz to investigate the effects of ultrasonic vibration on the indentation mechanics of Plasticine. A finite element simulation was employed as basis for interpreting the experimental data. The model incorporated material and geometric non-linearity and the slide line method for modeling contact problems. The finite element results show that stress superposition only accounts for part of the load reduction measured under superimposed ultrasonic vibration, and that there are no temperature changes during the process. Consequently, the reduction in indentation load may be attributed to a combination of stress superposition and friction reduction.

An improved quasi-1D strain SHPB method was used to study the dynamic mechanical behavior of materials under passive confining pressure state. The effects of mechanical behavior of the confining jacket material and its geometrical sizes on the experimental results are discussed. Thus the dynamical Poisson's ratio s dynamical Young's modulus E_s and dynamical compressive yield strength Y of the material at high strain rate can be obtained. The frictional force between the specimen and jacket and its effects on the axial stress-strain relationship under passive confining pressure are further analyzed. The correction to the elastic constants of the material was given.

A two-degree-of-freedom system impacting a single stop is considered. Unusual routes form periodic impact to chaos are investigated by numerical simulation. The periodic impact motion and its period doubling bifurcation are obtained by experimental method. The global bifurcation process form periodic impact to chaos includes both period-doubling bifurcation and Hopf bifurcation. The routes to chaos are qualitatively very different to those in the usual consecutive maps. Grazing discontinuities in the Poincare map are likely to be a major cause of unusual routes to chaos for the vibro-impact system.

The deformation behaviors of guardrails under both static and impact transverse loads and their contributions to the energy absorption are studied experimentally in this paper. Scaling-down tests are conducted and the specimens are about one-third of the real engineering guardrails in geometry. In order to measure the contribution of each kind of deformation to the energy absorption with the variation of transverse loads, single loading and multiple loading-unloading procedures are used in the static experiments. The impact tests are carried out in a drop-hammer system, and the effects of different boundary conditions on the energy absorption and peak load are investigated.

Anti-jamming techniques were studied in dynamic stress test on bogie structure form the hardware and software. The paper sums up the hardware techniques like compound protection technique and anti-radiation jamming technique; and mainly introduces the software techniques such as zero drift signal processing, digital signal filtering processing, and wavelet signal processing. Additionally, an algorithm 'three-peak-valley stress value compare' is proposed in the wavelet signal processing. The results in application prove these measurements help to provide valid and reliable stress-time history signals for programming the bogie stress spectrum.

The governing equations of 2D velocity and stream function expanded in general curvilinear coordinates base don tensor calculus are attained. The numerical algorithms of covariant, anti-covariant metric tensor and Christoffel symbols of the first and second kinds are described in this paper. This method could be extended readily to arbitrary stream surfaces.

A group of streamwise vortices in the near wall region of turbulent boundary layer are introduced by a group of parallel longitudinal heating wires to control the multi-scale eddy structures in wall turbulence. The relations between the introduced streamwise vortices and the multi-scale eddy structures in wall turbulence are studied. The influence of introduced streamwise vortices on multi-scale eddy structures in wall turbulence is analyzed by wavelet transform. The integrated kinetic energy of eddy structures at each scale is enhanced by the parallel heating wires. The characteristic time scales of different size eddy structures are changed by the introduced streamwise vortices.

In this paper an experiment on wake of Goldfish swimming unrestricted was conducted in a water tunnel. Method of color liquid was used to visualize the wake. Results show that there is reverse Karman vortex street in symmetrical plane of the wake and the Strouhal frequency of the fish is in the range 0.25-0.35. A 3D vortex ring chain model was presented.

The concept of the free-vortex aerodynamic windows (FADW) is one of the best effective methods taking the place of the conventional beam output crystal windows of high power laser. An experimental model of the supersonic free-vortex aerodynamic window has been designed and made in our latest study. This paper studies the aero-optical phenomena of the FADWs supersonic jet to realize the laser optical quality degradation caused by the free- vortex jet, and to find out the relation of output laser beam quality through the FADW to the structure of the FADWs shearing interferometry. At last the structure of FADWs jet has been studied by means of shearography.

Three-wedged nozzle was used to control turbulent structures generated form circular orifice. Experimental data were acquired with HWA and processed with spectrum analysis and wavelet transform. Similar results were obtained that relatively large structures are dominated at the exit edges for both circular jet and 3-wedge jet. Much higher frequency signals presenting small structures are detected near the core region. Compared with circular jet, the structures of higher frequency in 3-wedge jet show that the tabs on the exit nozzle make turbulent mixing efficient at relatively small scales. The frequency of vortex shedding at the tip of the wedge was obtained and it is consistent with the theoretical value.

The discovery of large-scale structures termed as spanwise vortices in the middle seventies last century may be the origin of the study of coherent structures. Until now, however, the puzzle-Do large-scale structures exist in fully developed turbulence-is still open, and the controversy about the effect of the initial disturbances on the spatial evolution of large-scale structures in plane mixing layers does not attain a conclusion. We studied these problems to a certain extend by flow visualizations. A kind of the streamwise structures termed as helical structures was widely discovered in plane mixing layers in our experiments. This streamwise structure was also discovered in the low Reynolds number round jets numerically and in the countercurrent axisymmetric shear flows experimentally, and its spatial evolution has nothing to do with the flow fields-plane or axisymmetric mixing.

The inter-vertebra disc is an important part of human lumbar spine, it is valuable to examine the lumbar spine and inter- vertebra disc by means of bio-mechanics. A new testing method is described in this paper for inner stress measuring, the test data is verified by the other test method, which is satisfying, which is satisfying. The results of this paper establish the foundation of the inter-vertebra disc core study, and it is helpful in the clinic and practical application.

The paper demonstrates stress relaxation experimental result of human adult fresh corpse trachea, and examines various effects related to human trachea stress and time, and treats the experimental dat in regression analysis method. Study conclusion reveals normalization stress relaxation function and curve of trachea viscoelastic mechanic mechanism and makes analysis and discussion of experimental results.

In this paper, we review a method of mechanical experiment on the arterial wall and propose a dynamic mechanical experiment. We also do static experiment to compare with the dynamic one. We find that there is an offset between the dynamic curve and the static curve, that is to say, the ranges of radius in the dynamic and static experiments are different in the same range of pressure. The materials of the arterial wall have the property of self-adaptability in a mechanical environment. The increment elastic modulus of small deformation can not be obtained by differentiation directly from the stress-strain of large deformation.

Individualized Products are one of the ten mega trends of the 21st Century with human modeling as the key issue for tomorrow's design and product development. The use of human modeling software for computer based ergonomic simulations within the production process increases quality while reducing costs by 30- 50 percent and shortening production time. This presentation focuses on the use of human 3D-CAD models for both, the ergonomic design of working environments and made to measure garment production. Today, the entire production chain can be designed, individualized models generated and analyzed in 3D computer environments. Anthropometric design for ergonomics is matched to human needs, thus preserving health. Ergonomic simulation includes topics as human vision, reachability, kinematics, force and comfort analysis and international design capabilities. In German more than 17 billions of Mark are moved to other industries, because clothes do not fit. Individual clothing tailored to the customer's preference means surplus value, pleasure and perfect fit. The body scanning technology is the key to generation and use of human 3D-CAD models for both, the ergonomic design of working environments and made to measure garment production.

Total knee replacement requires high measurement accuracy and fixation precision in surgical operation. Misplacement larger than 5 degrees in the force line alignment will lead to re- operation or long term deficits. Based on conventional operation facilities, it was not easy to ensure the necessary precision during het surgery. With the help of CT images, 3D images of patient's knee can be reconstructed. With IR localizer, computer- assisted knee surgical navigation can be realized by tracking that is useful for accurate alignment in surgery and in visualized training program.

This thesis analyses the traditional plum blossom needle and the in-revolve needle. And according to the experiment data, we conclude that the in-revolve needle in marrow is better than the traditional plum blossom in that against torsion and bending. This theory basis is important to clinical.