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Добірка наукової літератури з теми "Quasi-static crack evolution"

Автор: Grafiati

Опубліковано: 14 березня 2023

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Статті в журналах з теми "Quasi-static crack evolution"

NEGRI, MATTEO, and CHRISTOPH ORTNER. "QUASI-STATIC CRACK PROPAGATION BY GRIFFITH'S CRITERION." Mathematical Models and Methods in Applied Sciences 18, no. 11 (November 2008): 1895–925. http://dx.doi.org/10.1142/s0218202508003236.

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Анотація:

We consider the propagation of a crack in a brittle material along a prescribed crack path and define a quasi-static evolution by means of stationary points of the free energy. We show that this evolution satisfies Griffith's criterion in a suitable form which takes into account both stable and unstable propagations, as well as an energy balance formula which accounts for dissipation in the unstable regime. If the load is monotonically increasing, this solution is explicit and almost everywhere unique. For more general loads we construct a solution via time discretization. Finally, we consider a finite element discretization of the problem and prove convergence of the discrete solutions.

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Hentati, Hamdi, Radhi Abdelmoula, Aref Maalej, and Khalil Maalej. "Quasi Static Analysis of Anti-Plane Shear Crack." Applied Mechanics and Materials 232 (November 2012): 92–96. http://dx.doi.org/10.4028/www.scientific.net/amm.232.92.

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Fracture mechanics has been revisited by proposing different models of quasi static brittle fracture. In this work, the problem of the quasi static crack propagation is based on variational approach. It requires no prior knowledge of the crack path or of its topology. Moreover, it is capable of modeling crack initiation. In the numerical experiments, we use a standard linear (P1) Lagrange finite element method for discretization. We perform numerical simulations of a piece of brittle material without initial crack. An alternate minimizations algorithm is used. Based on these numerical results, we determine the influence of numerical parameters on the evolution of energies and crack propagation. We show also the necessity of considering the kinetic term and the crack propagation becomes dynamic.

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Almi, Stefano. "Quasi-static hydraulic crack growth driven by Darcy’s law." Advances in Calculus of Variations 11, no. 2 (April 1, 2018): 161–91. http://dx.doi.org/10.1515/acv-2016-0029.

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AbstractIn the framework of rate independent processes, we present a variational model of quasi-static crack growth in hydraulic fracture. We first introduce the energy functional and study the equilibrium conditions of an unbounded linearly elastic body subject to a remote strain {\epsilon\in\mathbb{R}} and with a sufficiently regular crack Γ filled by a volume V of incompressible fluid. In particular, we are able to find the pressure p of the fluid inside the crack as a function of Γ, V, and ϵ. Then we study the problem of quasi-static evolution for our model, imposing that the fluid volume V and the fluid pressure p are related by Darcy’s law. We show the existence of such an evolution, and we prove that it satisfies a weak notion of the so-called Griffith’s criterion.

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Negri, Matteo, and Rodica Toader. "Scaling in fracture mechanics by Bažant law: From finite to linearized elasticity." Mathematical Models and Methods in Applied Sciences 25, no. 07 (April 14, 2015): 1389–420. http://dx.doi.org/10.1142/s0218202515500360.

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We consider crack propagation in brittle nonlinear elastic materials in the context of quasi-static evolutions of energetic type. Given a sequence of self-similar domains nΩ on which the imposed boundary conditions scale according to Bažant's law, we show, in agreement with several experimental data, that the corresponding sequence of evolutions converges (for n → ∞) to the evolution of a crack in a brittle linear-elastic material.

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Maso, Gianni Dal, and Chiara Zanini. "Quasi-static crack growth for a cohesive zone model with prescribed crack path." Proceedings of the Royal Society of Edinburgh: Section A Mathematics 137, no. 2 (2007): 253–79. http://dx.doi.org/10.1017/s030821050500079x.

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Анотація:

In this paper we study the quasi-static crack growth for a cohesive zone model. We assume that the crack path is prescribed and we study the time evolution of the crack in the framework of the variational theory of rate-independent processes.

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Yasin Said, Mohamed, and Jianjun Chen. "Study on Defect Evolution of Steel Strip under High-speed Cold Rolling." Journal of Physics: Conference Series 2430, no. 1 (February 1, 2023): 012023. http://dx.doi.org/10.1088/1742-6596/2430/1/012023.

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Abstract In this paper the strain rate effect of the material was quantitatively tested by INSTRON tensile testing machine and Zwick/Roell HTM5020 high-speed tensile testing machine. The dimple size of the fracture surface of the tensile specimen was determined and analyzed by using the scanning electron microscope. Based on the Cowper-Symonds constitutive model, the parameters in the dynamic constitutive model and the true stress-strain curve under quasi-static condition were obtained by combining the results of quasi-static and dynamic tensile tests and the finite element numerical analyses. Considering the strain rate effect of the material the effects of cold rolling speed on the evolution of different types of defects were analyzed by the ANSYS/LS-DYNA dynamics code. The results show that with the increasing of crack length and decreasing of crack width, the critical rolling speed decreases. But if the crack length is less than 5 mm and the aspect ratio of crack length to crack width is larger than 5, the critical rolling speed of crack growth can be much large.

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J. Larsen, Christopher. "Local minimality and crack prediction in quasi-static Griffith fracture evolution." Discrete & Continuous Dynamical Systems - S 6, no. 1 (2013): 121–29. http://dx.doi.org/10.3934/dcdss.2013.6.121.

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Nifagin, V. A., and M. A. Gundina. "QUASISTATIC STATIONARY GROWTH OF ELASTOPLASTICAL CRACK." Vestnik of Samara University. Natural Science Series 20, no. 7 (May 30, 2017): 85–95. http://dx.doi.org/10.18287/2541-7525-2014-20-7-85-95.

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Анотація:

The boundary value problem with relations to the theory of ﬂow with non- linear hardening in derivatives stress and strain tensors in the parameter loading is formulated to estimate local mechanical properties in the vicinity of crack tip of mode of loading for plane strain of elastic-plastic material at the stage of quasi-static growth. Complete solutions are obtained by the method of asymp- totic decompositions. The redistribution of stress and strain ﬁelds in the plastic region at quasi-static growing crack for the intermediate structure is investigat- ed. The form of plastic zones was found in the evolution of fracture process of material. We also obtained direct estimates of errors and diameters of con- vergence when dropping residues of series.

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Li, Ling, EA Flores-Johnson, Luming Shen, and Gwénaëlle Proust. "Effects of heat treatment and strain rate on the microstructure and mechanical properties of 6061 Al alloy." International Journal of Damage Mechanics 25, no. 1 (January 23, 2015): 26–41. http://dx.doi.org/10.1177/1056789515569088.

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In the present work, the effects of heat treatment and strain rate on mechanical behaviour and microstructure evolution of aluminium alloy 6061 have been investigated. The micro-crack initiation and crystallographic texture evolution are obtained from scanning electron microscope and electron back-scatter diffraction experiments. Quasi-static and high strain rate compression tests are conducted on AA6061 specimens that underwent two different heat treatments: the as-received material with the original T6 heat treatment and the heat treated and artificially aged specimens. For the high strain rate compression (∼2000 and ∼4000 s−1) tests, the split Hopkinson pressure bar apparatus is used. It is observed that the additional heat treatment has significantly reduced the yield strength of the material. Furthermore, electron back-scatter diffraction results show that the higher the applied strain rate is, the less significant change will happen to the texture. Scanning electron microscope images show that, for both T6 and HT specimens, the number and size of micro-cracks in the dynamic compressed specimens are smaller than in the quasi-static deformed specimen. Therefore, the strain rate is considered to be the dominant factor in forming micro-cracks.

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Nozères, Frédéric, Hervé Couque, Rémi Boulanger, Yann Quirion, Patrice Bailly, and Jérôme Limido. "Numerical modelling strategies using implicit and explicit methods to simulate quasi-static and dynamic three-points bend fracture tests of a ductile steel." EPJ Web of Conferences 250 (2021): 02033. http://dx.doi.org/10.1051/epjconf/202125002033.

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Three-point bend fracture tests have been conducted at different loading rates with a quadratic martensitic steel. The failure energy has been found to increase with loading rate. To get insights in this increase a numerical investigation has been undertaken with different strategies using ABAQUS and IMPETUS softwares in order to address quasi-static and dynamic loading conditions. Simulations were conducted with the ABAQUS software in order to carry out a comparative analysis of both implicit and explicit approaches. In addition to standard Finite Element Method (FEM) applied to quasi-static and dynamic conditions, the eXtended-Finite Element Method (X-FEM) was applied to quasistatic conditions. In both approaches, implicit and explicit, crack initiation and propagation were governed by a critical plastic strain threshold combined with a displacement-based damage evolution criterion. Simulations conducted with the IMPETUS software use an explicit approach and second order elements for both quasi-static and dynamic loading conditions. A node-splitting method using an energy-based damage criterion was employed to simulate the crack initiation and propagation. Experimental data and numerical results have been compared, allowing to determine the ability of these two softwares to simulate accurately three-point bend fracture tests.

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Більше джерел

Дисертації з теми "Quasi-static crack evolution"

Racca, Simone. "Some models of crack growth in brittle materials." Doctoral thesis, SISSA, 2013. http://hdl.handle.net/20.500.11767/4809.

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Анотація:

This work is devoted to the study of models of fractures growth in brittle elastic materials; it collects the results obtained during my Ph.D., that are contained in [77, 76, 78]. We consider quasi-static rate-independent models, as well as rate-dependent ones and the case in which the first ones are limits of the second ones when certain physical parameters vanish. The term quasistatic means that, at each instant, the system is assumed to be in equilibrium with respect to its time-dependent data; this setting is typical of systems whose internal time scale is much smaller than that of the loadings. By rate-independent system we mean that, if the time-dependent data are rescaled by a strictly monotone increasing function, then the system reacts by rescaling the solutions in the same manner.

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Almi, Stefano. "Some results on the mathematical analysis of crack problems with forces applied on the fracture lips." Doctoral thesis, SISSA, 2016. http://hdl.handle.net/20.500.11767/4878.

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Анотація:

This thesis is devoted to the study of some models of fracture growth in elastic materials, characterized by the presence of forces acting on the crack lips. Working in the general framework of rate-independent processes, we first discuss a variational formulation of the problem of quasi-static crack evolution in hydraulic fracture. Then, we investigate the crack growth process in a cohesive fracture model, showing the existence of an evolution satisfying a weak Griffith's criterion. Finally, in the last chapter of this work we investigate, in the static case, the interaction between the energy spent in order to create a new fracture and the energy spent by the applied surface forces. This leads us to study the lower semicontinuity properties of a free discontinuity functional F(u) that can be written as the sum of a crack term, depending on the jump set of u, and of a boundary term, depending on the trace of u.

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Частини книг з теми "Quasi-static crack evolution"

Babadjian, Jean-François. "Stability of Quasi-Static Crack Evolution through Dimensional Reduction." In IUTAM Symposium on Variational Concepts with Applications to the Mechanics of Materials, 1–13. Dordrecht: Springer Netherlands, 2010. http://dx.doi.org/10.1007/978-90-481-9195-6_1.

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Negri, Matteo. "Quasi-Static Evolutions in Brittle Fracture Generated by Gradient Flows: Sharp Crack and Phase-Field Approaches." In Innovative Numerical Approaches for Multi-Field and Multi-Scale Problems, 197–216. Cham: Springer International Publishing, 2016. http://dx.doi.org/10.1007/978-3-319-39022-2_9.

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Тези доповідей конференцій з теми "Quasi-static crack evolution"

Koch, Brendan M. L., Calvin Lo, Tomoko Sano, and James David Hogan. "Bulking as a Mechanism in the Failure of Advanced Ceramics." In 2019 15th Hypervelocity Impact Symposium. American Society of Mechanical Engineers, 2019. http://dx.doi.org/10.1115/hvis2019-022.

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Abstract Failure in brittle materials is characterized by crack growth and fracture, processes which involve an increase in the volume of a sample to accommodate these cracks. This process is called bulking and it is known to be an important factor in the failure of materials such as ceramics, stone, and concrete. While volumetric strains are obtainable under quasi-static conditions, under dynamic conditions technical challenges have stood in the way of obtaining multi-dimensional strain data that would allow for assessment of bulking under the sort loading conditions that would simulate a high velocity impact. Advances in digital-image-correlation and ultra-high-speed-photography have however opened up the capacity to obtain this higher dimensional data. This data in turn has prompted an assessment of prior theory to produce a framework through which stress-strain behavior can be expressed in terms of changes to multiple elastic constants simultaneously. This presentation offers initial results in quasi-static and dynamic experiments and discusses the implications for brittle material behavior and crack evolution phenomenon under a variety of conditions.

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Bhattacharya, Debdeep, Patrick Diehl, and Robert P. Lipton. "Peridynamics for Quasistatic Fracture Modeling." In ASME 2021 International Mechanical Engineering Congress and Exposition. American Society of Mechanical Engineers, 2021. http://dx.doi.org/10.1115/imece2021-70793.

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Abstract Fracture involves interaction across large and small length scales. With the application of enough stress or strain to a brittle material, atomistic scale bonds will break, leading to fracture of the macroscopic specimen. From the perspective of mechanics fracture should appear as an emergent phenomena generated by a continuum field theory eliminating the need for a supplemental kinetic relation describing crack growth. We develop a new fast method for modeling quasi-static fracture using peridynamics. We apply fixed point theory and model stable crack evolution for hard and soft loading. For soft loading we recover unstable fracture. For hard loading we recover stable crack growth. We show existence of quasistatic fracture solutions in the neighborhood of stable critical points for appropriately defined energies. The numerical method uses an analytic stiffness matrix for fast numerical implementation. A rigorous mathematical analysis shows that the method converges for load paths associated with soft and hard loading. For soft loading the crack becomes unstable shortly after the stress at the tip of the pre-crack reaches the material strength.

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Khan, Rizwan A., and Suhail Ahmad. "Probabilistic Fatigue Safety Analysis of Oil and Gas Risers Under Random Loads." In ASME 2010 29th International Conference on Ocean, Offshore and Arctic Engineering. ASMEDC, 2010. http://dx.doi.org/10.1115/omae2010-20464.

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Marine riser is an important component of oil and gas drilling and production system. It is essentially a slender pipe conveying fluid between well-head and floating production unit. They are formed out of three basic types of configuration namely, free hanging, “lazy-wave (SWLR)” riser. Risers are subjected to varied static, quasi-static and dynamic forces. For the safety of design, the behavior of the riser under these forces is thoroughly investigated. 3D Nonlinear dynamic analysis of riser is obtained in the time domain using finite element software package ABAQUS/Aqua. The response histories so obtained are employed for the study of fatigue reliability analyses of riser. It is based on a bi-linear relationship to model fatigue crack growth and incorporates a failure criterion to describe the interaction between fracture and plastic collapse. Uncertainty modeling, especially of fatigue crack growth parameters, is undertaken using bi-linear crack growth relationship. Results pertaining to fatigue reliability and fatigue crack size evolution are presented using Monte Carlo Simulation. The bi-linear crack growth models are found to lead to higher fatigue life estimation. Sensitivity behavior pertinent to limit state adopted has been thoroughly investigated. These findings implicate inspection schemes for components of the marine structures to ensure minimization of the surprises due to wide scatter of the fatigue phenomenon in marine environment.

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Montesano, John, and Chandra Veer Singh. "Development of a Synergistic Damage Mechanics-Based Model for Predicting Multiaxial Effects in Progressive Failure of Composite Structures." In ASME 2014 International Mechanical Engineering Congress and Exposition. American Society of Mechanical Engineers, 2014. http://dx.doi.org/10.1115/imece2014-38109.

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A major benefit of advanced fiber-reinforced polymer composites is that they can be tailored and optimized to suit a particular structural application by orienting the reinforcing fibers along multiple directions. For practical load-bearing structural components manufactured from multidirectional laminates, predicting their mechanical behaviour is quite complex. This is specifically the case for progressive failure analysis of these materials when subjected to quasi-static or fatigue loading since local cracks will initiate and evolve in multiple directions simultaneously. The difficulty of the problem increases further when these laminates are subjected to complex multiaxial stress states. This is due to the fact that the multidirectional crack state will be subjected to additional crack driving stress components, which will ultimately alter the crack evolution characteristics. A synergistic damage mechanics (SDM) methodology has recently been developed to address these issues in progressive damage analyses of composite laminates containing multiple damage modes and subjected to uniaxial loading [1]. By combining micromechanics and continuum damage mechanics, the SDM methodology provides a rigorous and practical tool for accurate prediction of progressive damage behaviour in composite structures. This is essential for accurately predicting the integrity and durability of practical structures, which will lead to safer and more efficient designs.

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Sengezer, Engin Cem, and Gary D. Seidel. "Experimental Characterization of Strain and Damage Evolution in Carbon Nanotube-Polymer Nanocomposites." In ASME 2014 Conference on Smart Materials, Adaptive Structures and Intelligent Systems. American Society of Mechanical Engineers, 2014. http://dx.doi.org/10.1115/smasis2014-7612.

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An experimental characterization of nanocomposite strain and damage sensing in support of development of CNT-polymer nanocomposites for structural health monitoring (SHM) applications was conducted. As such, effort here is focused towards examining the piezoresistive behavior of poly(dimethyl-siloxane) (PDMS) and epoxy filled with acid treated single walled carbon nanotubes (COOH-SWNTs) under quasi-static compression and tension. Precision LCR Meter with two terminal method, in conjunction with mechanical testing and data acquisition system were used to measure instantaneous resistance values. Given the emphasis on SHM applications which correlate changes in electrical resistivity to deformation and damage, 0.1 wt% COOH-SWCNTs concentration below the nanocomposite electrical percolation threshold was considered for PDMS and epoxy. Measurements confirmed the onset of damage prior to noticeable effects in the stress-strain response. The resistance measurements were able to both detect strain for PDMS nanocomposites and damage initiation and provide continuous assessment of the damage state between damage initiation events for epoxy nanocomposites. Digital Image Correlation (DIC) System was used to observe the crack propagation on notched epoxy nanocomposite compact tension samples.

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Lall, Pradeep, Aathi Raja Ram Pandurangan, and Ken Blecker. "Evolution of Potting-PCB Interfacial Reliability After Long Term High Temperature Operation." In ASME 2021 International Technical Conference and Exhibition on Packaging and Integration of Electronic and Photonic Microsystems. American Society of Mechanical Engineers, 2021. http://dx.doi.org/10.1115/ipack2021-74062.

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Abstract Fine Pitch Electronic Components are reinforced using epoxy potting compounds and underfills to improve reliability and survivability, in extreme environments. Potting of electronic components offers structural support, shock damping and protection for the components from environmental conditions like moisture. Potting is one of the cost-effective and viable way to improve the survivability of the electronic components. On dynamic shock loading, interfacial delamination occurs between the potting material and the PCB, which further propagates to solder interconnect failures. The interfacial properties change with long-term exposure to temperature during operating and storage conditions. Mechanics of interface delamination of the epoxy potted PCB samples with thermal aging is a primary focus on this paper. Determination of fracture parameters such as fracture toughness and strain energy release rate at steady state stress is important in selection of the potting material and the reliability study of the supplemental restraint systems. PCB/Epoxy specimens are prepared, and their fracture behavior is observed under quasi-static three-point and four-point bend loading. In three-point bending, the peak stress acts at the midpoint of the specimen. In four-point bend loading, the peak stress is along whole area of the specimen under load (load span). The curing temperature providing the best fracture resistance is selected and followed throughout the study. The samples are exposed to 100°C for 30days and 60 days. Under dynamic loading, damage at the interface is studied. The experimental results provide the peak critical load, from which the fracture toughness parameters are calculated. A comparison has been made on fracture toughness and crack initiation of the PCB/Epoxy systems, based on flexure method and thermal aging.

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SURATKAR, AADITYA, JOHN MONTESANO, and JEFFREY WOOD. "DAMAGE EVOLUTION IN NON-CRIMP FABRIC CARBON FIBER/EPOXY MULTI-DIRECTIONAL LAMINATES UNDER QUASI-STATIC TENSION." In Thirty-sixth Technical Conference. Destech Publications, Inc., 2021. http://dx.doi.org/10.12783/asc36/35921.

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An experimental study was performed to characterize the evolution of damage in a unidirectional Non-Crimp Fabric (NCF) carbon fiber/snap-cure epoxy composite under in-plane quasi-static tensile loads. The NCF composites were manufactured using a High Pressure-Resin Transfer Molding (HP-RTM) process and comprised a fast-curing epoxy resin and heavy tow unidirectional carbon fiber NCF layers. Laminates with stacking sequences [0/±45/90] and [±45/0 ] were subjected to axial and transverse quasi-static tensile loads and an in-situ Edge replication (ER) technique was used to capture the damage evolution at predefined intervals. An imprint of the composite microstructure, as observed on the edges of a test coupon, was created on a cellulose acetate replicating tape, which was then observed under the microscope. The onset and progression of ply cracks and delamination, which were the two major damage modes present, were quantified and correlated with the stress-strain curves and changes in stiffness. The influence of stacking sequence and ply thickness are also captured.

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Littlewood, David J., Kyran Mish, and Kendall Pierson. "Peridynamic Simulation of Damage Evolution for Structural Health Monitoring." In ASME 2012 International Mechanical Engineering Congress and Exposition. American Society of Mechanical Engineers, 2012. http://dx.doi.org/10.1115/imece2012-86400.

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Modal-based methods for structural health monitoring require the identification of characteristic frequencies associated with a structure’s primary modes of failure. A major difficulty is the extraction of damage-related frequency shifts from the large set of often benign frequency shifts observed experimentally. In this study, we apply peridynamics in combination with modal analysis for the prediction of characteristic frequency shifts throughout the damage evolution process. Peridynamics, a nonlocal extension of continuum mechanics, is unique in its ability to capture progressive material damage. The application of modal analysis to peridynamic models enables the tracking of structural modes and characteristic frequencies over the course of a simulation. Shifts in characteristic frequencies resulting from evolving structural damage can then be isolated and utilized in the analysis of frequency responses observed experimentally. We present a methodology for quasi-static peridynamic analyses, including the solution of the eigenvalue problem for identification of structural modes. Repeated solution of the eigenvalue problem over the course of a transient simulation yields a data set from which critical shifts in modal frequencies can be isolated. The application of peridynamics to modal analysis is demonstrated on the benchmark problem of a simply-supported beam. The computed natural frequencies of an undamaged beam are found to agree well with the classical local solution. Analyses in the presence of cracks of various lengths are shown to reveal frequency shifts associated with structural damage.

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Karvelas, C., G. Chatzopoulou, A. D. Zervaki, N. Stathas, E. Strepelias, X. Palios, S. N. Bousias, and S. A. Karamanos. "Mechanical Response of an Industrial Piping System Under Strong Cyclic Loading." In ASME 2021 Pressure Vessels & Piping Conference. American Society of Mechanical Engineers, 2021. http://dx.doi.org/10.1115/pvp2021-62273.

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Abstract The paper presents a combined experimental and numerical investigation of cyclic loading response of an internally pressurized steel piping system. The piping system comprises three elbows and is subjected to quasi-static end-displacement excitation. Global deformation and local strain measurements are obtained, indicating significant strain ratcheting at the critical locations of the elbows. The piping system failed under low-cycle fatigue undergoing through-thickness cracking at the flank of the most strained elbow. Post-fatigue metallographic examination of the elbows indicated that fatigue cracking initiates from the inner surface of the pipe elbow. In all elbows, several micro-cracks develop along the inner surface of elbow flanks, whereas the outer surface remained practically intact before through-thickness cracking. Finite element simulations, with a properly calibrated cyclic-plasticity model calibrated properly in terms of small-scale material tests, provide very good predictions in terms of local strain evolution at critical locations.

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BUENROSTRO, JAVIER, and HYONNY KIM. "EXPERIMENTAL CHARACTERIZATION OF THE IN-PLANE SHEAR RESPONSE OF WOVEN POLYMER MATRIX COMPOSITES UNDER INTERMEDIATE STRAIN RATES." In Proceedings for the American Society for Composites-Thirty Seventh Technical Conference. Destech Publications, Inc., 2022. http://dx.doi.org/10.12783/asc37/36489.

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The need for advanced material models to simulate the process of deformation, damage and failure of polymer matrix composites (PMCs) under impact conditions is becoming critical as these materials are gaining increased usage in the aerospace and automotive industries. Experimental stress vs. strain curves are needed at different strain rates for progressive damage modeling of dynamic failure. Matrix-dominated deformation modes are particularly challenging as they exhibit nonlinear behavior and rate dependence. In particular, in-plane shear is known to exhibit significant nonlinear response due its matrix dominant deformation leading up to failure. The purpose of this work is to experimentally characterize the in-plane shear deformation response of woven carbon/epoxy fabrics under intermediate strain rates (10-1 to 100 s-1). For this work, plain weave carbon fabrics with 3k and 12k tows are manufactured by VARTM. Testing is done using a servo-hydraulic load frame and 2D digital image correlation (DIC) is used to obtain experimental stress vs. strain curves following ASTM D7078M. Comparison between quasi-static (10-3 s-1) and intermediate experimental stress strain curves show an increase in ultimate strength and no significant change in modulus with increased loading rate. Investigations into the development of areas of localized high strain are observed which are attributed to the growth of meso-scale fiber tows damage. Surface level measurements from DIC and qualitative observations from high speed camera imaging reveal that cracks initiate and develop in the matrix gap between tows and at fiber undulation regions of the plain weave. These then develop into bulk cracks that grow parallel to the load. Higher loading rates have shown increased strength under in-plane. In conclusion, 2D DIC and the v-notched shear test method was able to characterize rate effects under intermediate shear loading of woven polymer matrix composites deformation response. High resolution DIC reveals localized mesoscale strain inhomogeneity that plays a key role in the initiation and evolution of bulk fracture in woven composite architecture which was captured for well for the 12k tow material.

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