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Showing 1 to 16 of 16 for “"Critical stress intensity factor"”.
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Fracture of Hot-Pressed Silicon Nitride at Elevated Temperatures
… point bend at three displacement rates. Fracture stress and critical stress intensity factor were calculated and plotted versus temperature for each displacement rate. The scanning electron microscope, transmission electron microscope and scanning Auger electron spectrometer were used to analyze …
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Morphology Development and Fracture Properties of Toughened Epoxy Thermosets
… did not change with cure temperature, the critical stress intensity factor did not vary significantly with cure temperature as expected. However, increases in cure temperature produced smaller but more numerous particles. The critical stress intensity factor normalized by the number density …
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Fracture characterization of clays and clay-like materials using flattened Brazilian Test
… tool in studying fracture in rock, is the critical stress intensity factor that defines stress concentration near a crack tip beyond which a fracture would propagate. The basic mode of crack loading can be obtained by applying a normal stress that has a corresponding opening mode of crack …
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Experimental and seismological constraints on the rheology, evolution, and alteration of the lithosphere at oceanic spreading centers
… rates are linearly dependent on effective mean stress when the effective mean stress is low and non-linearly dependent on effective mean stress when it is high. Microearthquakes recorded above an inferred magma reservoir along the TAG segment of the Mid-Atlantic Ridge delineate for the first …
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Fiber Orientation Effects on the Fracture and Flexural Toughness of Extruded Fiber Reinforced Concrete for Additive Manufacturing
… since they are aligned parallel to the tensile stresses produced in flexure testing. The FRCC employed 0.5% and 1% polyvinyl alcohol (PVA) fiber reinforcement by volume. The flexural properties of FRCC were determined using four-point bend tests according to a modified ASTM C1609. Calculations …
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Experimental and seismological constraints on the rheology, evolution, and alteration of the lithosphere at oceanic spreading centers
… rates are linearly dependent on effective mean stress when the effective mean stress is low and non-linearly dependent on effective mean stress when it is high. Microearthquakes recorded above an inferred magma reservoir along the TAG segment of the Mid-Atlantic Ridge delineate for the first …
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Applicability Of Continuum Fracture Mechanics In Atomistic Systems
<p>By quantitating the amplitude of the unbounded stress, the continuum fracture mechanics defines the stress intensity factor K to characterize the stress and displacement fields in the vicinity of the crack tip, thereby developing the relation between the stress singularity and surface energy …
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Global-local Finite Element Fracture Analysis of Curvilinearly Stiffened Panels and Adhesive Joints
… cracks to be defined in the vicinity of the critical stress zone. With the damage tolerance study of unitized structures as the focus, responses of curvilinearly stiffened panels to the combined shear and compression loadings were studied for different stiffeners' height. It was observed that …
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Study of layer orientation on the fracture behavior of two additively manufactured thermoset resins, A
… using a least square fit to extract the evolving critical stress intensity factor (SIF) leading to fracture initiation. These results are compared to quasi-static experiments of the same material and similar geometries on a standard load frame. Findings suggest that the print orientation does …
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Mechanical behaviour and fracture toughness of unfilled and short fibre filled polypropylene both drawn and undrawn. Experimental investigation the effect of fibre content and draw ratio on the mechanical properties of unfilled and short glass fibre filled polypropylene
… matrix and their destruction in the compressive stress field thus restoring the interfacial contact area between fibre and matrix. Unfilled and short glass fibre filled polypropylene specimens, with fibre content 7% wt, 13%wt, 27%wt, and 55%wt, were injection moulded prior to the die drawing …
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Fracture Characteristics of Concretes and Cement-Stabilized Soil
… to the cracking and failure of concrete under stress has been receiving considerable attention. Most of these investigations have been directed towards the determination of the critical stress intensity factor or fracture toughness of concrete, mortar, or cement paste, failing in tension. …
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Prediction of service load of concrete structures after cracking using ultrasonic technique
… toughness of the concrete member in terms of critical stress intensity factor, KICe. The model was evaluated for size dependency using several sizes of notched beams with different notch lengths. The results showed fracture toughness in terms of KICe , to be size-independent up to a crack over …
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Leveraging Carbon Based Nanoparticle Dispersions for Fracture Toughness Enhancement and Electro-mechanical Sensing in Multifunctional Composites
… according to ASTM D5045 test procedure and the critical stress intensity factor, $K_{IC}$, and the critical fracture energy, $G_{IC}$, were calculated for all the material systems. Significant enhancements relative to neat epoxy were observed in reinforced epoxies. Fracture surfaces were …
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Effect of grain structure and doping on the mechanical properties of polysilicon thin films for MEMS
… that are prone to failure due to large operating stresses. Polycrystalline silicon (polysilicon) films with improved mechanical properties to meet demanding applications could be engineered by modification of the material microstructure. Such advances require detailed experimental studies and …
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Fractionated reclaimed asphalt pavement as a coarse aggregate replacement in a ternary blended concrete pavement
… edge notched beam specimens revealed that the critical stress intensity factor was generally reduced with the addition of FRAP. Despite the reduction in tensile strength and peak load at specimen failure with increasing quantities of FRAP replacement, both the total fracture energy and initial …
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Chemomechanical modeling of hydrogen-induced degradation at high temperatures
… and the operating conditions, e.g., applied stress level and time. The API publication presents a series of Nelson curves specific to various steel compositions that are used extensively in the refining and petrochemical industries. These curves establish the safe operation regimes in a …