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Search theses and dissertations gathered from participating repositories worldwide. Every result links back to the library that holds it. No account is needed.
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Showing 1 to 20 of 20 for “"transverse isotropy"”.
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Concentrated Force Problems in Transverse Isotropy
Made available in DSpace on 2014-12-13T19:31:50Z (GMT). No. of bitstreams: 1 7913640.pdf: 2270027 bytes, checksum: 6495dd59170c6ef15909528e0899d7a8 (MD5) Previous issue date: 1978
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Shell finite elements, with applications in biomechanics
… constitutive theory extended to take account of transverse isotropy. The finite element formulation is given in such a way as to make various implementational aspects clear. Implementation has been carried out in deal.II, an open source library of finite element code. Substantial detail is given …
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Failure Prediction of Spatial Wood Structures: Geometric and Material Nonlinear Finite Element Analysis
… considerations include 3-d beam finite elements, transverse isotropy, torsional warping, beam-decking connectors, beam-beam connectors, geometric and material nonlinearities, and the discretization of pressure loads. The primary objective of this study is to test the hypothesis that the …
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Geomechanics and elastic anisotropy of the Bakken Formation, Williston Basin
… rocks exhibit anisotropic characteristics. Anisotropy is particularly common in many sedimentary rocks, such as shales. Anisotropy is defined as the spatial alignment of mineral grains, layers, fractures and stresses which causes elastic wave velocity and other elastic properties to vary with …
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Seismic anisotropy in siliciclastic reservoir rocks
… of geophysical field measurements of seismic anisotropy is presently limited by our knowledge of the controls of the elastic anisotropy of sedimentary rocks in the subsurface. Traditionally, laboratory ultrasonic velocity measurements have been used to provide important information on bulk …
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Failure and deformation of rocks in compression for underground design
… that took into account stress transformation, transverse isotropy, and the calculation of the effective elastic moduli due to cracks. Simple examples were taken to verify the results of the numerical analyses.
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Physical Modeling and Analysis of Seismic Data from a Simulated Fractured Medium
… the fracture orientation and magnitude of the anisotropy of a naturally fractured medium. The simulated fractured medium is constructed from phenolic LE-grade material which exhibits orthorhombic symmetry. For initial characterization of the phenolic model, its elastic sti ness coe cients were …
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Non-linear finite element analyses of the aortic heart valve
… valve leaflets. As natural leaflets show anisotropy with a pronounced stiff direction along the circumference of the valve, isotropic models of the leaflets were extended to account for this behaviour by incorporating transverse isotropy. The results display a stark impact of a transversely …
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Experimental investigation of a novel finite element model for Southern pine glulam beams
… measured at three locations along the length. Transverse isotropy and global modulus of elasticity were assumed ,to determine experimentally beam material properties: longitudinal modulus of elasticity and shear modulus. The analysis was performed by using the finite element program ABAQUS. The …
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Linear elastic fracture mechanics in anisotropic solids : application to fluid-driven crack propagation
… solids. Notably, a special attention is paid to transverse isotropy, often used to model rocks but also some piezoelectric materials or fiber-reinforced composites. We focus on brittle materials, that is, we consider only elastic deformations; we thus ignore dissipative phenomena other than the …
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Optimal Blast-Resistant Sandwich Structures with Transversely Isotropic, Elasto-plastic Polymeric Foams as Cores
… Unlike metallic foams polymeric foams exhibit transversely isotropic response when tested in a laboratory setting. More specifically, they exhibit different hardening along the foam thickness than that in a direction transverse to the thickness. Furthermore, polymeric foams harden differently …
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Non-Destructive Evaluation and Mathematical Modeling of Beef Loins Subjected to High Hydrodynamic Pressure Treatment
… realistic deformation response assuming transverse isotropy of the model beef loin. The last study correlated small- and large-strain measurements using stress relaxation and elastic coefficients of the stiffness matrix as small-strain measures and results of the study indicated very high …
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Rock Physics Study of Lacustrine Shales and Applications in Geophysical Prediction of Sweet Spot
… of reservoir samples possess significant transverse-isotropy type anisotropy and velocity dispersion and attenuation. Furthermore, I synthesized the geological and discussed physical mechanisms to explain my measured data and observation. The anisotropy of the lacustrine shale is primarily …
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Peridynamic Investigation of Stress-Strain Response and Fracture Behavior Variations in Micro-CT Images of Mock Energetic Nanocomposites
… for the material as image number increased. The isotropy investigation and averaged results indicated that the composite was transversely isotropic. The stress vs. strain curve for the damage-enabled cases were nearly identical for the y-direction and x-direction conditions, with a maximum …
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Boundary-value problems for transversely isotropic hyperelastic solids
… theory for Cauchy elastic isotropic and transversely isotropic solids follows, with reference to which, the notion of a hyperelastic solid is then prescribed. Further, the necessary connections with the classical linear theory of transversely isotropic solids are generated and finally …
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Anisotropic media and the determination of subsurface velocity by the use of surface seismic reflection data
Velocity anisotropy is present at a point in a medium if the seismic velocity in one direction in general differs from that in another direction. The problems associated with the determination of subsurface velocity in anisotropic media by the use of surface seismic reflection data are analyzed. …
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Geometrically nonlinear finite element analysis of a glulam timber dome
… is assumed to be continuous, homogeneous, and transversely isotropic. The material properties are assumed to be constant through the volume of the element. The transverse isotropy assumption is validated for southern pine by testing small samples in torsion. The accuracy of the modeling …
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Propagation of fluid driven fractures in transversely isotropic material
… media is well established, the impact of the anisotropy of natural rocks on HF propagation is still far from being understood. Sedimentary rocks like shales and mudstones are ubiquitous in upper earth crust which are made of fine layers which result in transverse isotropy. In the framework of …
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Finite Deformations of Fiber-Reinforced Rubberlike Solids, and of Adhesively Bonded T-peel Joints
… rubberlike material can be modeled as transversely isotropic with the fiber direction as the axis of transverse isotropy, we express the stored energy function, W, in terms of the five invariants of the right Cauchy-Green strain tensor and the fiber direction, and account for different …
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Borehole Breakouts in Transversely Isotropic Posidonia Shale
… shales show marked elasticity and strength anisotropy, which can be attributed to a macroscopic distribution and orientation of soft and hard minerals. Under load the hard minerals form a load-bearing, supporting structure, while the soft minerals compensate the deformation. Therefore, if …