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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 36 for “"Strain Softening"”.
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The Mechanical Properties of Individual Electrospun Fibers and Fibrin Fibers
… a bending modulus of 7.5 GPa. Both fibers show strain softening, however, collagen shows extreme strain softening and therefore only a bending modulus is given. Native crosslinked fibrin fibers have similar properties to electrospun fibrinogen fibers. Crosslinked fibers have an extensibility of …
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Static and Seismic Stability of Cut Slopes in Terms of Reliability
… the static stability of a cut slope formed by strain-softening soil such as highly overconsolidated clay considering progressive failure as the critical failure mode. The stress condition along a potential failure surface both prior to and after an excavation is investigated by finite-element …
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A study of localized failure modes in brittle materials
… of materials which exhibit instabilities due to strain softening or geometric effects. Localization in finite element modelling of brittle materials such as concrete and rock is a relatively unexplored area in computational mechanics, and this work applies current concepts to an isotropic damage …
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Bestimmung der Materialparameter gefüllter Elastomere in Abhängigkeit von Zeit, Temperatur und Beanspruchungszustand
… the description of the temperature dependency of strain crystallization processes. Additionally a concept is developed, which also permits a consideration of strain softening effects with material models used in today's FEA programs. An emphasis of these investigations is the question, which …
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Finite element study of geosynthetic encased stone columns in sensitive soft clay
… strength sensitivity, ie these soil manifest strain softening when shear in an undrained mode. These soils, referred to as sensitive soft soils, have the typical features of strain hardening in drained shearing and strain softening in undrained shearing. The consolidation lines of these soils …
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The Role of Soil Stiffness in Reverse Fault Rupture Propagation
… nonlinear Mohr-Coulomb constitutive model with a strain dependent yield surface and non-associated flow was employed to study the plastic soil properties which affect the rate of surface fault rupture propagation in reverse events. These numerical simulations show a trend for soils with higher …
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Image-Based Geotechnical Constitutive Model Parameter Calibration
… is somewhat at odds with reality beyond small strains. Often, when conventional tests are ill-suited for calibrating a particular material parameter, multiple model-specific tests are proposed which increase the "cost" of the implementation of such constitutive models. However, advances in …
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Thermally-induced ratcheting behaviour of laterally-loaded reinforced concrete energy piles in sand
… from simple elastic-perfectly plastic, to strain hardening, and strain softening was evaluated. The soil nonlinearity concerning an equivalent mobilised shear modulus was essential to capture the pre-peak load-displacement response of the laterally loaded pile. It could be incorporated into …
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Deformation and fracture of polycarbonate and rubber-modified polycarbonate under controlled temperature, deformation rate, and notch stress triaxiality
… particles are investigated. The effects of strain rate, temperature, and notch stress triaxiality on deformation and fracture are studied. The Arruda-Boyce constitutive model for glassy polymers and finite element simulations are used to simulate the deformation of the polycarbonate …
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The Influence of Pore Fluid on The Stability of a Rock Mass With a Weakened Zone
… effects of dilatant hardening and diffusive softening on the stability of saturated rock is investigated. The analysis considers an infinite slab of fluid-infiltrated rock which contains a sublayer of weakened material. Inelastic deformation is allowed throughout the slab, with strain …
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Failure and deformation of rocks in compression for underground design
… was developed to predict the nonlinear stress-strain behavior of coal including strain-hardening and strain-softening. In order to solve problems with complex boundary conditions, this model was implemented into two and three dimensional finite element programs. The implementation involved a …
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Improving Continuum Models for Excavations in Rockmasses Under High Stress Through an Enhanced Understanding of Post-Yield Dilatancy
… be adequately represented using a conventional strain-softening approach, an existing model for dilatancy can be applied. As is shown in this thesis, the use of a constant dilation angle to approximate the dilatant behaviour of the rockmass in this case is appropriate; accordingly, parameter …
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Design of Si/SiC hybrid structures for elevated temperature micro-turbomachinery
thermal softening behavior at temperatures above 900 K. This thermal softening behavior limits the turbine inlet temperature, which in turn significantly degrades the overall engine efficiency. Previous studies have shown that hybrid structures of silicon and silicon carbide have good potential for …
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Identification, Mapping, Analysis, and Dating of Composite Mega Landslides in the Colorado Plateau
… shales. The shales are susceptible to creep and strain softening where lateral confinement has been removed by the downcutting of the Colorado River and its tributaries. Strata dipping towards valleys, including dips of 5 degrees or less, greatly impact the number and scale of landslide events. …
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Enhanced Anisotropic Bounding Surface Model: Implementation and Simulation of Excavation in Soft Cohesive Soils
… types of cohesive soils, including those with strain softening behavior. The capability and limitation of the bounding surface models are assessed, and it is confirmed that complex soil behavior, such as the effects of stress anisotropy and over-consolidation nature, can practically be …
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Linear and Non-Linear Mechanical Nature of a Living Mammalian Cytoplasm
… that the cytoplasm of a living cell undergoes strain softening and shear thinning when locally subjected to weakly nonlinear oscillatory deformations.
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Engineering properties of Resedimented Ugnu Clay from the Alaskan North Slope
… petroleum exploration. Thirteen constant rate of strain (CRS) tests were performed to ascertain the compression properties as a function of consolidation stress. Consolidation stress for these specimens ranged from 6,800 kPa to 39,000 kPa. CRS results show that the compression ratio (CR) decreases …
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The undrained behavior of saturated, dilatant silts
… intergranular forces and influence the stress-strain behavior of the soil in undrained tests. Variations in the amount of dissolved gas exiting solution and forming bubbles from one specimen to another could be the cause of the erratic undrained behavior often observed for saturated silts. …
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Testing and constitutive modelling of saturated interfaces in dynamic soil-structure interaction.
… Also, a constitutive model for the stress-strain-pore-pressure behavior of cohesive soil interfaces under dynamic loading is developed using the new unified disturbed state concept (DSC). The model is based on elasto-plasticity theory as defined by the hierarchical single surface (HISS) …
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Discontinuous modelling of strain localisation and failure
… to a finite element as an incompatible strain mode. This allows a traction–separation relationship to be applied at an interface and can be implemented simply in a standard finite element code. It is however shown that this type of model can be cast in an equivalent continuum format, a …
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