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Showing 1 to 20 of 37 for “"ductile failure"”.
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Lifetime Estimation for Ductile Failure in Semicrystalline Polymer Pipes
… and compression. Subsequently, creep rupture failure of the pipes under hydrostatic pressure is predicted using the model. The model predictions are validated using the experimental creep rupture failure data collected from internal pressurization of pipes using a custom-designed, fully …
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A new approach for predicting brittle or ductile failure of rock in deep excavations
L'abstract è presente nell'allegato / the abstract is in the attachment
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Finite Element Analysis of Thermoviscoplastic Deformations of an Impact-Loaded Prenotched Plate
… the sense that at low speed of impact, a brittle failure ensues at a point on the upper surface of the notch tip. However, at high impact speeds, a ductile failure in the form of a shear band initiates first from a point on the lower surface of the notch tip. The predicted speed at which the …
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Linking Rheological and Processing Behavior to Molecular Structure in Sparsely-Branched Polyethylenes Using Constitutive Relationships
… relationship. A flow instability known as ductile failure in extensional flow required the development a novel technique known as encapsulation in order to carry out shear-free rheological characterization. Ductile failure prevents the rheological measurement of transient stress growth at …
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Modeling of sheet metal fracture for shell finite elements with component level validation
Ductile fracture causing premature failure of parts during forming and crash has become an important factor limiting design of car bodies. The increasing usage of advanced high strength steels and other lightweight materials to meet ever-stringent standards on passenger safety and gas emissions …
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Use of acoustic emission to study deformation of mild steel in hydrogen and nitrogen environments
… tested in nitrogen typically failed by bursting (ductile failure) while those tested in hydrogen typically failed by leaking ("brittle" failure).
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Elevated temperature mechanical properties and corrosion characteristics evaluation of alloy Ht-9
… (SSR) technique, revealed higher failure stress (sigmaf) at longer tempering time. Localized corrosion studies conducted by polarization technique showed pitting and crevice corrosion in specimens exposed to both neutral and acidic environments. The fractographic evaluations of the …
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Performance of C-Shaped structural concrete walls subjected to bi-directional loading
… walls. The experimental tests exhibited a ductile failure resulting from loss of boundary element confinement, bar buckling, and rupture of the longitudinal bars. However, the ductile failure mechanism was precipitated by increased shear deformation and undesirable shear related damage of …
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Deformation and fracture of polycarbonate and rubber-modified polycarbonate under controlled temperature, deformation rate, and notch stress triaxiality
… it begins to travel into the grip region, ductile failure occurs due to extensive stretching. The fracture is surface initiated. The load at yield is shown to be dependent on temperature and displacement rate. The load at yield increases with increasing strain rate and decreases with …
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Concrete Bridge Girders with Exposed Flexural Reinforcement
… the typical behaviour, including probable failure modes, of reinforced concrete specimens with exposed flexural reinforcement. Based on these findings, two analytical approaches are developed to predict the longest length of flexural reinforcement that could be exposed that ensures a girder …
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The Ductile to Brittle Transition in Polycarbonate
… and rate-dependent in order to simulate the ductile to brittle failure transition in polycarbonate. The cohesive zone model is motivated by experimental evidence that two different critical energies per unit area of crack growth exist in glassy polymers. A higher energy state is associated …
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Seismic Performance of Precast Concrete Flooring Systems
… potentially vulnerable to earthquake induced non-ductile failure modes and that had not been previously tested. To achieve this objective, the performance of precast concrete flooring systems during the Canterbury earthquakes was reviewed and the observed damage was compared with failure modes …
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Structure property and deformation analysis of polypropylene montmorillonite nanocomposites.
… wave imaging allowed the identification of ductile failure among materials, but more important, aided the mapping of the elastic and plastic contributions. These are essential concepts in fracture analysis.
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Application of Ductile Yield Link in Glulam Moment Connections
… of this research was to develop and test a ductile and high-strength wood moment frame connection. A design procedure for such a connection is presented herein. The proposed glulam beam-column connection utilizes an embedded steel knife plate with a reduced section that acts as a ductile …
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Performance of Pressure Sensitive Adhesive Tapes In Wood Light-Frame Shear Walls
… OSB and plywood connections provided fairly ductile failure modes. Full-scale walls constructed with adhesive tape performed similarly to traditional wall configurations, while walls constructed with a combination of adhesive tape and mechanical fasteners provided significant gains in …
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Design and construction of a motor-actuated sea ice compression testing machine
… rates around 4 x 10-4/s, which falls within the ductile-to-brittle transition zone, where maximum ice compressive strength is expected. The tested samples exhibited ductile failure modes in ice cores, with maximum stress observed before a gradual stress relaxation. Notably, the maximum stress …
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Modeling Microvoid Localization with Explicit Finite Element Analysis
Ductile fracture is characterized by the micromechanisms of void nucleation, growth, and coalescence. Numerical modeling of these micromechanical phenomena has typically been performed with an implicit finite element analysis (FEA) solver, which accurately produces quasi-static results, but …
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Flexural Behavior of Carbon/Epoxy IsoTruss Reinforced-Concrete Beam-Columns
… the flexural behavior (strength, stiffness and failure) of IsoTruss®-reinforced concrete beam-columns for use in deep foundation pile applications. Four-point bending tests were performed in the laboratory on two instrumented carbon/epoxy IsoTruss® reinforced concrete piles (IRC piles) and two …
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Rayleigh Wave Acoustic Emission during Crack Propagation in Steel
… surface pulses (SSP) on crack faces in near-failure fatigue. An SSP has components of various modes of wave propagation. The component with the largest amplitude is a Rayleigh surface wave pulse. The possibility that these surface modes have much higher amplitudes than bulk modes of acoustic …
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Numerical Simulation of Adiabatic Shear Bands and Crack Propagation in Thermoviscoplastic Materials
… the formation and propagation of brittle and ductile fracture. Deformations of the impact loaded double edge-crack specimen of Kalthoff and Winkler (1987) are studied. The brittle to ductile failure mode transition with increasing impact speed was found. Previous studies have focused on …
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