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Showing 1 to 11 of 11 for “"Strain rate effect"”.
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Determination of material properties of mild steel at different temperatures and strain rates
… yield stress of mild steel with temperature and strain rate. This was achieved by carrying out high temperature tensile tests at different strain rates on mild steel specimens. These experiments also helped set a methodology for carrying out high temperature tensile tests using a servohydraulic …
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Dynamic modelling of lightweight high-strength concrete under impact
… (LWHSC) under static and dynamic loadings. A new strain-based damage model is developed based on continuum damage mechanics. The proposed model incorporates the strain rate effects on various concrete properties, such as tensile and compressive strengths, critical strains and elastic moduli. In …
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Determination of geotechnical properties of seafloor sediment using a free fall penetrometer
… penetration with rigid probes in saturated sediments usually results in an increase in measured penetration resistance. This effect, called the strain rate effect, was studied for soft fine-grained sediments by formulating a model to determine undrained shear strength …
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Dynamic Shear Bands in Metals under High Strain Rates
… constitutive models that take temperature and strain rate effect into account are proposed. The first model is a physically based model that depends on basic physical quantities, such as dislocation densities, Burgers vector, and activation energy. The second model is a simple empirical power …
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High-Strain Rate Tensile Characterization Of Graphite Platelet Reinforced Vinyl Ester Based Nanocomposites Using Split-Hopkinson Pressure Bar
… high-speed digital photography. The on-specimen strain gage installation is substituted by a non-contact Laser Occlusion Expansion Gage (LOEG) technique for infinitesimal dynamic tensile strain measurements. Due to very low transmitted pulse signal, an alternative approach based on incident pulse …
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Rate Effects in Fine Grained Soils
The strain rate dependent behaviour of fine grained soils is an important aspect of geotechnical engineering. During dynamic or rapid events such as earthquakes and rapid pile testing, a fine grained soil will display significantly different behaviour than may be observed over the long life span of …
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An experimental study on time-dependent behaviour of reconstituted clayey soils in 1D and triaxial compression
Accurate assessment of the safe performance of geotechnical structures against the time-dependent strength-deformation behaviour of soils relies on the knowledge acquired from laboratory and field experiments. Therefore, the focus of this research is to experimentally investigate the role of stress …
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Enhancement of crashworthiness in car-truck collisions using damped under-ride guard and composite crush elements
… finite element analysis are discussed to illustrate the relative merits of the methods. The crashworthiness of the automobile impacting heavy freight vehicles is further enhanced by incorporating crush elements to absorb the impact energy. Experimental studies are conducted to enhance an …
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Limiting factors of the tensile strength of aramid fibers
… of fibers. Tension tests conducted at different strain rates showed that the permanent orientation of crystalline domains at high strains/stresses scales inversely with the applied strain rate. Notably, at strain rates of 0.2-0.3 s -1 both as-spun and heat-treated fibers were linearly elastic …
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An investigation of liquefied shear strength using novel centrifuge tests, direct simple shear tests, and field case histories
… the relationship between su(liq) and pre-failure effective vertical stress might be slightly nonlinear. Direct simple shear (DSS) laboratory element tests under controlled drainage conditions performed were used to characterize the critical state properties of three nonplastic soils, including the …
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Alternate Load Paths and Retrofits for Long-span Truss Bridges under Sudden Member Loss and Blast Loads
… collapse of the I-35W truss bridge has demonstrated the vulnerabilities of long-span truss bridges, and their societal and economic consequences under the abnormal events, such as sudden loss of a critical member or members and the explosive attacks. These long-span truss bridges that are …