Journal articles: 'Shear Modulus of Elasticity'

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Cramer, Steven, David Kretschmann, Roderic Lakes, and Troy Schmidt. "Earlywood and latewood elastic properties in loblolly pine." Holzforschung 59, no. 5 (September 1, 2005): 531–38. http://dx.doi.org/10.1515/hf.2005.088.

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Abstract The elastic properties of earlywood and latewood and their variability were measured in 388 specimens from six loblolly pine trees in a commercial plantation. Properties measured included longitudinal modulus of elasticity, shear modulus, specific gravity, microfibril angle and presence of compression wood. Novel testing procedures were developed to measure properties from specimens of 1 mm×1 mm×30 mm from earlywood or latewood. The elastic properties varied substantially circumferentially around a given ring and this variation was nearly as large as the variation across rings. The elastic properties varied by ring and height, but while the modulus of elasticity increased with height, the shear modulus decreased with height. A strong correlation was found between modulus of elasticity and shear modulus, but only at low heights and inner rings. Specific gravity and microfibril angle were the strongest predictors of elastic properties and explained 75% of the variation in modulus of elasticity for latewood. Despite being the best predictors in this study, these parameters accounted for less than half of the variability of earlywood modulus of elasticity, earlywood shear modulus and latewood shear modulus.

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Yang, Jian, Donghua Liao, Jingbo Zhao, and Hans Gregersen. "Shear Modulus of Elasticity of the Esophagus." Annals of Biomedical Engineering 32, no. 9 (September 2004): 1223–30. http://dx.doi.org/10.1114/b:abme.0000039356.24821.6c.

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Deng, S. X., J. Tomioka, J. C. Debes, and Y. C. Fung. "New experiments on shear modulus of elasticity of arteries." American Journal of Physiology-Heart and Circulatory Physiology 266, no. 1 (January 1, 1994): H1—H10. http://dx.doi.org/10.1152/ajpheart.1994.266.1.h1.

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Although the mechanical properties of blood vessels have been studied extensively, the shear modulus of the blood vessel wall is still unknown. New data on the shear modulus of elasticity of rat arteries and its variation with axial stretch and blood pressure are presented. The data were obtained from a new instrument designed and constructed by us to perform simultaneous torsion, inflation, and longitudinal stretching tests. It was found under physiological conditions (pressure = 120 mmHg or 16 kPa; longitudinal stretch = 1.2 relative to zero-stress state), the shear modulus of normal rat thoracic aorta is G = 137 +/- 18 kPa. The difference of shear modulus at body temperature (37 degrees C) and room temperature (25 degrees C) is within 10%. The shear modulus varies significantly with changing longitudinal and circumferential strains in proportion to the strain energy due to these strains. A constitutive equation based on a pseudo strain energy function is proposed. The vessel wall is not transversely isotropic in the incremental sense. When the rat was subjected to high blood pressure due to constriction of its aorta, the shear modulus does not vary significantly with the length of time the animal was subjected to hypertension.

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Jorda, Johannes, Günther Kain, Marius-Catalin Barbu, Alexander Petutschnigg, and Pavel Král. "Influence of Adhesive Systems on the Mechanical and Physical Properties of Flax Fiber Reinforced Beech Plywood." Polymers 13, no. 18 (September 13, 2021): 3086. http://dx.doi.org/10.3390/polym13183086.

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In order to improve the acceptance of broader industrial application of flax fiber reinforced beech (Fagus sylvatica L.) plywood, five different industrial applicated adhesive systems were tested. Epoxy resin, urea-formaldehyde, melamine-urea formaldehyde, isocyanate MDI prepolymer, and polyurethane displayed a divergent picture in improving the mechanical properties—modulus of elasticity, modulus of rupture, tensile strength, shear strength and screw withdrawal resistance—of flax fiber-reinforced plywood. Epoxy resin is well suited for flax fiber reinforcement, whereas urea-formaldehyde, melamine urea-formaldehyde, and isocyanate prepolymer improved modulus of elasticity, modulus of rupture, shear strength, and screw withdrawal resistance, but lowered tensile strength. Polyurethane lowered the mechanical properties of flax fiber reinforced plywood. Flax fiber reinforced epoxy resin bonded plywood exceeded glass fiber reinforced plywood in terms of shear strength, modulus of elasticity, and modulus of rupture.

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Labašová, Eva. "Determination of Modulus of Elasticity and Shear Modulus by the Measurement of Relative Strains." Research Papers Faculty of Materials Science and Technology Slovak University of Technology 24, no. 39 (December 1, 2016): 85–92. http://dx.doi.org/10.1515/rput-2016-0021.

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Abstract This contribution is focused on determining the material properties (Young modulus and shear modulus) of the testing samples. The theoretical basis for determining material properties are the knowledge of linear elasticity and strength. The starting points are dependencies among the modulus of elasticity, shear modulus, normal stress and relative strain. The relative strains of the testing samples were obtained by measuring predefined load conditions using a strain-gauge bridge and the universal measurement system Quantum X MX 840. The integration of these tasks into the teaching process enhances practical and intellectual skills of students at secondary level technical universities.

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Prošek, Zdeněk, and Jaroslav Topič. "LONG-TIME INVESTIGATION OF CEMENT COMPOSITE MATERIAL WITH MICRONIZED WASTE MARBLE POWDER: DYNAMIC MODULES." Acta Polytechnica CTU Proceedings 13 (November 13, 2017): 93. http://dx.doi.org/10.14311/app.2017.13.0093.

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This article focus on “blended cement”. The blended cement was created by using waste marble powder (WMP) as a partial replacement for cement. We investigated the influence of WMP on the developing of the dynamic modulus of elasticity and the dynamic shear modulus in time. Four different cement composites with WMP as a partial replacement for cement were studied (5, 10, 15 and 50 wt. %) together with reference samples. Dynamic modulus of elasticity was monitored during the first 377 days since manufacture by use of non-destructive testing (resonance method). The results showed that WMP in a small amount had a no effect on the dynamic modulus of elasticity and the dynamic shear modulus.

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Miyamoto, Naokazu, and Kosuke Hirata. "Moderate Associations of Muscle Elasticity of the Hamstring with Hip Joint Flexibility." International Journal of Sports Medicine 40, no. 11 (August 19, 2019): 717–24. http://dx.doi.org/10.1055/a-0981-7282.

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AbstractThe main purpose of the present study was to identify whether and to what extent the individual differences in range of motion and stiffness of the hip joint can account for that in muscle elasticity of the hamstring. Hip extension torque and shear moduli (a measure of elasticity) of the biceps femoris, semitendinosus, and semimembranosus were assessed in 21 young males during unilateral passive hip flexion in the knee-extended position from the anatomical position to the individual’s maximal hip flexion angle. Muscle shear modulus was quantified by using ultrasound shear wave elastography. The maximal hip flexion angle correlated negatively with the shear modulus of each muscle (−0.750 ≤ r ≤ −0.612). The joint stiffness correlated positively with the shear modulus of each muscle (0.711 ≤ r ≤ 0.747). These findings suggest that hip flexion ROM and joint stiffness can reflect significantly but only moderately the muscle elasticity of the hamstring.

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Völp, Annika R., and Norbert Willenbacher. "Shear modulus and yield stress of foams: contribution of interfacial elasticity." Soft Matter 17, no. 14 (2021): 3937–44. http://dx.doi.org/10.1039/d0sm02246b.

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A general correlation of foam shear modulus G₀ and yield stress τ_y with the interfacial elastic modulus of foaming solutions in shear and dilation E_∞ was found for surfactant, block-copolymer, protein, food, and particle-stabilized foams.

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Yang, Peng, Hong Zhi Cui, and Wei Lun Wang. "Visco-Elasticity of Asphalt Mixture under Broad Temperature and Frequency." Advanced Materials Research 838-841 (November 2013): 156–61. http://dx.doi.org/10.4028/www.scientific.net/amr.838-841.156.

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In this study, the improved model of CAM with clear parameter was introduced. The visco-elasticity of asphalt mixture under broad temperature and frequency was studied and the properties of asphalt mixture at high asphalt and low temperature of was described by fitting the parameters of CAM model. The four equations of CAM model can be utilized in analysis of visco-elasticity of asphalt mixture and the physical meaning of the parameters in equations was very clear; Through nonlinear curve fitting , the CAM model was found to overcome the defect of deviation from the start and the end fitting; For one kind of asphalt mixture, the complex shear modulus and storage shear modulus was higher in same frequency at lower temperature, and the elasticity was in dominant position significantly; At middle temperature, the modulus of asphalt mixture became smaller; At high temperature, although the modulus was lower, the elasticity was higher. At middle-high temperature, the modulus of asphalt mixture remained smaller and the ratio of elasticity was minimum value, and asphalt mixture was recognized as typical visco-elastic body and was destroyed easily by the deformation disease.

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Yu, Jing, Yongmei Zhang, Yuhong Zhao, and Yue Ma. "Anisotropies in Elasticity, Sound Velocity, and Minimum Thermal Conductivity of Low Borides VxBy Compounds." Metals 11, no. 4 (April 1, 2021): 577. http://dx.doi.org/10.3390/met11040577.

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Anisotropies in the elasticity, sound velocity, and minimum thermal conductivity of low borides VB, V5B6, V3B4, and V2B3 are discussed using the first-principles calculations. The various elastic anisotropic indexes (AU, Acomp, and Ashear), three-dimensional (3D) surface contours, and their planar projections among different crystallographic planes of bulk modulus, shear modulus, and Young’s modulus are used to characterize elastic anisotropy. The bulk, shear, and Young’s moduli all show relatively strong degrees of anisotropy. With increased B content, the degree of anisotropy of the bulk modulus increases while those of the shear modulus and Young’s modulus decrease. The anisotropies of the sound velocity in the different planes show obvious differences. Meanwhile, the minimum thermal conductivity shows little dependence on crystallographic direction.

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Liu, Fenglu, Houjiang Zhang, Fang Jiang, Xiping Wang, and Cheng Guan. "Variations in Orthotropic Elastic Constants of Green Chinese Larch from Pith to Sapwood." Forests 10, no. 5 (May 25, 2019): 456. http://dx.doi.org/10.3390/f10050456.

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Full sets of elastic constants of green Chinese larch (Larix principis-rupprechtii Mayr) with 95% moisture content at four different cross-section sampling positions (from pith to sapwood) were determined in this work using three-point bending and compression tests. Variations in the material constants of green Chinese larch from pith to sapwood were investigated and analyzed. The results showed that the sensitivity of each elastic constant to the sampling position was different, and the coefficient of variation ranged from 4.3% to 48.7%. The Poisson’s ratios νRT measured at four different sampling positions were similar and the differences between them were not significant. The coefficient of variation for Poisson’s ratio νRT was only 4.3%. The four sampling positions had similar Poisson’s ratios νTL, though the coefficient of variation was 11.7%. The Poisson’s ratio νLT had the greatest variation in all elastic constants with a 48.7% coefficient of variation. A good linear relationship was observed between the longitudinal modulus of elastic EL, shear modulus of elasticity GRT, Poisson’s ratio νRT, and sampling distance. EL, GRT, and νRT all increased with sampling distance R. However, a quadratic relationship existed with the tangential modulus of elasticity ET, radial modulus of elasticity ER, shear modulus of elasticity GLT, and shear modulus of elasticity GLR. A discrete relationship was found in the other five Poisson’s ratios. The results of this study provide the factual changes in the elastic constants of green wood from pith to sapwood for numerical modelling of stress wave propagation in trees or logs.

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André Luis, Christoforo, Panzera Tulio Hallak, Silva Diogo Aparecido Lopes, Fiorelli Juliano, and Lahr Francisco Antonio Rocco. "Shear and Longitudinal Modulus of Elasticity in Structural Lumber Beams." International Journal of Materials Engineering 4, no. 1 (February 1, 2014): 31–36. http://dx.doi.org/10.5923/j.ijme.20140401.04.

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Wang, Ping. "The limiting case of zero shear modulus in linear elasticity." Journal of Elasticity 38, no. 2 (February 1995): 121–32. http://dx.doi.org/10.1007/bf00042494.

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Park, Dae Woo. "Ultrasound Shear Wave Simulation of Breast Tumor Using Nonlinear Tissue Elasticity." Computational and Mathematical Methods in Medicine 2016 (2016): 1–6. http://dx.doi.org/10.1155/2016/2541325.

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Shear wave elasticity imaging (SWEI) can assess the elasticity of tissues, but the shear modulus estimated in SWEI is often less sensitive to a subtle change of the stiffness that produces only small mechanical contrast to the background tissues. Because most soft tissues exhibit mechanical nonlinearity that differs in tissue types, mechanical contrast can be enhanced if the tissues are compressed. In this study, a finite element- (FE-) based simulation was performed for a breast tissue model, which consists of a circular (D: 10 mm, hard) tumor and surrounding tissue (soft). The SWEI was performed with 0% to 30% compression of the breast tissue model. The shear modulus of the tumor exhibited noticeably high nonlinearity compared to soft background tissue above 10% overall applied compression. As a result, the elastic modulus contrast of the tumor to the surrounding tissue was increased from 0.46 at 0% compression to 1.45 at 30% compression.

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Labašová, Eva, Rastislav Ďuriš, and Vladimír Labaš. "Determining of Shear Modulus for the Samples Circular and Hollow Circular Cross-Section." Materials Science Forum 862 (August 2016): 298–304. http://dx.doi.org/10.4028/www.scientific.net/msf.862.298.

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The contribution is focused on estimating the shear modulus of the samples of circular and hollow circular sections by static method. The samples were loaded by simple torsion, individual sections were stressed by shear stress. Theoretical basis are determined by linear elasticity and strength theory and they define the relation between shear modulus, maximum shear stress and relative strains. Relative strains are determined by using measurement apparatus and measurement system Quantum X MX 840.

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García-Aladín, María Fernanda, Humberto García, Juan Manuel Mosquera, and José Jaime García. "The Importance of Shear in the Deflection of Bamboo Beams." Key Engineering Materials 600 (March 2014): 87–96. http://dx.doi.org/10.4028/www.scientific.net/kem.600.87.

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According to the traditional theory of elasticity, the total deflection of a beam occurs due to the combined effect of both the bending moment and the shear force. In isotropic materials such as steel and concrete, the deflection due to shear is usually not taken into account since it represents only 1% of the total deformation approximately. However, in anisotropic materials such as bamboo, the deflection due to shear should be taken into account because it may represent more than 20% of the total deformation of the beam. To better predict the influence of the shear effect on the deflection of bamboo beams, the longitudinal Young ́s modulus and the shear modulus of Guadua angustifolia were determined through the application of repeated three-point bending tests of whole culms and small prismatic elements while aligning their length along the axial direction of the culm. In order to determine the value of the shear modulus, each test was carried out using four different spans. The end results for the culms were: the longitudinal modulus of elasticity E equal to 23525 MPa, and the shear modulus G equal to 298 MPa. Thus, the substantial difference between the Young ́s modulus and the shear modulus confirms the high anisotropy of bamboo, and results indicate that shear deformation should always be included for the calculation of deflections of bamboo structures. Furthermore, the significant differences between these values and those obtained with the small prismatic elements may be attributed to the anisotropy and heterogeneity of the material. However, more tests have to be accomplished to further corroborate these results and find other anisotropic elastic properties of the material.

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Nakao, Gakuto, Keigo Taniguchi, and Masaki Katayose. "Acute Effect of Active and Passive Static Stretching on Elastic Modulus of the Hamstrings." Sports Medicine International Open 02, no. 06 (November 2018): E163—E170. http://dx.doi.org/10.1055/a-0733-6957.

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AbstractThe purpose of this study was to investigate differences in the acute effects of passive knee extension (PKE) and active knee extension (AKE) stretching on the shear elastic modulus of the hamstrings. In 20 healthy men, maximum knee extension (maximum range of motion [ROM]) and shear elastic modulus of the hamstrings (biceps femoris long head, semitendinosus, semimembranosus) were measured before (Pre) and after (Post) AKE and PKE stretching. The maximum ROM during stretching was measured. In both stretching methods, maximum ROM increased and the shear elastic modulus decreased (p<0.01), but no difference was found between the procedures. No significant difference was observed in the maximum ROM during stretching between the procedures (p=0.06). The shear elastic modulus was significantly lower in the biceps femoris long head and semimembranosus than in the semitendinosus muscle (p<0.05). Static stretching with PKE and AKE stretching showed an increase in maximum ROM and a decrease in hamstring elasticity, but no difference was found between the methods. Both stretching protocols were effective for reducing elasticity of the biceps femoris long head and semimembranosus.

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Jin, Yuqi, Teng Yang, Hyeonu Heo, Arkadii Krokhin, Sheldon Q. Shi, Narendra Dahotre, Tae-Youl Choi, and Arup Neogi. "Novel 2D Dynamic Elasticity Maps for Inspection of Anisotropic Properties in Fused Deposition Modeling Objects." Polymers 12, no. 9 (August 30, 2020): 1966. http://dx.doi.org/10.3390/polym12091966.

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In this study, a novel ultrasonic non-destructive and non-invasive elastography method was introduced and demonstrated to evaluate the mechanical properties of fused deposition modeling 3D printed objects using two-dimensional dynamical elasticity mapping. Based on the recently investigated dynamic bulk modulus and effective density imaging technique, an angle-dependent dynamic shear modulus measurement was performed to extract the dynamic Young’s modulus distribution of the FDM structures. The elastographic image analysis demonstrated the presence of anisotropic dynamic shear modulus and dynamic Young’s modulus existing in the fused deposition modeling 3D printed objects. The non-destructive method also differentiated samples with high contrast property zones from that of low contrast property regions. The angle-dependent elasticity contrast behavior from the ultrasonic method was compared with conventional and static tensile tests characterization. A good correlation between the nondestructive technique and the tensile test measurements was observed.

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Youn, Sung Won, Kazumi Suda, Masaharu Takahashi, and Ryutaro Maeda. "A Study on Formability of a Polyimide Film by Using Visco-Elasticity Measurement and Hot-Embossing Tests." Materials Science Forum 561-565 (October 2007): 1189–92. http://dx.doi.org/10.4028/www.scientific.net/msf.561-565.1189.

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This study explores the dynamic mechanical properties (e.g., storage shear modulus, loss tangent and shear viscosity) and formability of a polyimide film by visco-elasticity measurement and hot-embossing tests. The variations of storage shear modulus, tangent delta and the shear viscosity were measured as a function of the temperature for two frequencies. As a polyimide goes through its glass transition, it exhibits dramatic decreases in shear modulus and viscosity as well as the peak of tangent delta, and continues to show strong dependence on frequency and temperature. Moreover, the filling characteristics (e.g., surface appearance, replicated depth and surface roughness) of polyimide were investigated by hot-embossing tests at different temperatures using a mold with an aspect ratio of 2.5:1.

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Douglas, J. E., T. L. Biddick, J. J. Thomason, and J. C. Jofriet. "Stress/strain behaviour of the equine laminar junction." Journal of Experimental Biology 201, no. 15 (August 1, 1998): 2287–97. http://dx.doi.org/10.1242/jeb.201.15.2287.

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The equine laminar junction plays a vital role in transferring the forces of weight-bearing between the epidermal hoof wall and the bone of the third phalanx, but the way in which it performs this function is poorly understood. Using samples from sites varying proximodistally and circumferentially around the hoof, the stress/strain behaviour of this tissue was characterised in three directions: radial tension and proximodistal and mediolateral shear. The influences of toe angle and length were also examined. For all three test directions, the modulus of elasticity increased with increasing strain magnitude. The mean modulus of elasticity in tension was 18.25+/-5.38 MPa (mean +/-1 S.D., N=116; mean strain 0. 25). In proximodistal shear, the mean shear modulus was 5.38+/-1.49 MPa (N=76; mean shear strain 0.48) and in mediolateral shear 2. 57+/-0.91 MPa (N=66; mean shear strain 0.81). In many cases, the individual hoof or horse from which the samples were taken significantly affected the value of the modulus, suggesting that mechanical history may affect the material properties of this tissue. Few biologically significant variations with location, toe length or toe angle were unambiguously demonstrated, suggesting that the material properties of the laminar junction are independent of position, despite apparent regional variations in function, and that foot shape is not a major determinant of material properties.

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Zhao, Xinbo, Yanli Sun, and Yue Mei. "A Size-Dependent Cost Function to Solve the Inverse Elasticity Problem." Applied Sciences 9, no. 9 (April 30, 2019): 1799. http://dx.doi.org/10.3390/app9091799.

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Characterizing nonhomogeneous elastic property distribution of solids is of great significance in various engineering fields. In this paper, we observe that the solution to the inverse problem utilizing the standard optimization-based inverse approach is sensitive to the sizes of inclusions. The standard optimization-based inverse approach minimizes a cost function, containing the absolute error between the measured and computed displacements in L2 norm. To address this issue, we propose a novel inverse scheme to characterize nonhomogeneous shear modulus distribution of solids. In this novel method, the cost function is modified, and is dependent on the size of the inclusions. A number of simulated experiments are performed, and demonstrate that the proposed approach is capable of improving the shear modulus contrast in inclusions and reducing the size sensitivity. Furthermore, a theoretical analysis is conducted to validate what we have observed in simulated experiments. This theoretical analysis reveals that what we have observed in the simulated experiments is not induced by the numerical issues Instead, the size sensitivity issue is induced by regularization. The findings of this work encourage us to propose new cost functions for the optimization-based inverse approach to improve the quality of the shear modulus reconstruction.

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Chen, Pei-Yu, Cho-Chiang Shih, Wei-Chen Lin, Teng Ma, Qifa Zhou, K. Shung, and Chih-Chung Huang. "High-Resolution Shear Wave Imaging of the Human Cornea Using a Dual-Element Transducer." Sensors 18, no. 12 (December 3, 2018): 4244. http://dx.doi.org/10.3390/s18124244.

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Estimating the corneal elasticity can provide valuable information for corneal pathologies and treatments. Ophthalmologic pathologies will invariably cause changes to the elasticity of the cornea. For example, keratoconus and the phototoxic effects of ultraviolet radiation usually increase the corneal elasticity. This makes a quantitative estimation of the elasticity of the human cornea important for ophthalmic diagnoses. The present study investigated the use of a proposed high-resolution shear wave imaging (HR-SWI) method based on a dual-element transducer (comprising an 8-MHz element for pushing and a 32-MHz element for imaging) for measuring the group shear wave velocity (GSWV) of the human cornea. An empirical Young’s modulus formula was used to accurately convert the GSWV to Young’s modulus. Four quantitative parameters, bias, resolution, contrast, and contrast-to-noise ratio (CNR), were measured in gelatin phantoms with two different concentrations (3% and 7%) to evaluate the performance of HR-SWI. The biases of gelatin phantoms (3% and 7%) were 5.88% and 0.78%, respectively. The contrast and CNR were 0.76, 1.31 and 3.22, 2.43 for the two-side and two-layer phantoms, respectively. The measured image resolutions of HR-SWI in the lateral and axial directions were 72 and 140 μm, respectively. The calculated phase SWV (PSWV) and their corresponding Young’s modulus from six human donors were 2.45 ± 0.48 m/s (1600 Hz) and 11.52 ± 7.81 kPa, respectively. All the experimental results validated the concept of HR-SWI and its ability for measuring the human corneal elasticity.

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Moisa, Raul, Tiberiu Medgyesi, Liviu Bereteu, Gheorghe Drăgănescu, Dorin Simoiu, and Marcela Sava. "Vibration Tests for Determination of Longitudinal Elasticity Modulus and Shear Modulus of some Structures Welded with Tubular Wire." Applied Mechanics and Materials 430 (September 2013): 101–7. http://dx.doi.org/10.4028/www.scientific.net/amm.430.101.

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The purpose of this paper is to determine Young's modulus and the shear modulus of some welded joints made with usual tubular steel by flexural vibration tests. This is the case of the type carbon steel plates S235 JR according to EN 10025, with a thickness of 3 mm welded with MIG/MAG welding process with R713 tubular wire with a diameter of 1.2 mm, using SelcoNeoMig 3500 equipment. The technological part is detailed: welding parameters used, advantages and disadvantages of tubular wires use, problems regarding ambient protection, punctual applications of welding procedures with tubular wire. Processing the obtained signal based on vibration response the elasticity modulus is determined and its value is then compared with the value of elasticity modulus obtained through tensile stress and also with the value obtained by theoretical way.

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Laurinavičius, Alfredas, and Rolandas Oginskas. "EXPERIMENTAL RESEARCH ON THE DEVELOPMENT OF RUTTING IN ASPHALT CONCRETE PAVEMENTS REINFORCED WITH GEOSYNTHETIC MATERIALS." JOURNAL OF CIVIL ENGINEERING AND MANAGEMENT 12, no. 4 (December 31, 2006): 311–17. http://dx.doi.org/10.3846/13923730.2006.9636408.

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The article sets out to explore reasons for the development of shear strains and rutting in asphalt pavement as well as to suggest and describe the main methods for reducing the deformation. The impact of geosynthetic materials is defined through reological characteristics of asphalt: the modulus of elasticity and the viscosity of asphalt. The research has been conducted on the experimental road section in the city of Vilnius. The measurements have been based on the plate‐bearing test. Sustaining the measurements results is defining the dependency of geosynthetics materials on the depth of rutting and the modulus of elasticity of asphalt concrete. The paper also includes regression equations which show the interdependence of the modulus of elasticity of asphalt concrete and the depth of rutting.

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Adjrad, Arezki, Youcef Bouafia, Mohand Said Kachi, and Hélène Dumontet. "Modeling of Externally Prestressed Beams until Fracture in Non Linear Elasticity." Applied Mechanics and Materials 749 (April 2015): 379–85. http://dx.doi.org/10.4028/www.scientific.net/amm.749.379.

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In this paper, we present an analytical model to analyze reinforced and prestressed concrete beams loaded in combined bending, axial load and shear, in the frame of non linear elasticity. In this model, the equilibrium of the beam is expressed by solving a system of equations, governing beams equilibrium, based on the stiffness matrix of the beam, which connects the load vector to the node displacements vector of the beam. It is built from the stiffness matrix of the section which takes into account a variation of the shearing modulus (depending on the shear variation) instead of assuming a constant shearing modulus as in linear elasticity. For the internal tendons, the stiffness matrix is completed by the terms due to the prestress effect in flexural equilibrium and by the balancing of one part of the shear by the transverse component of the force in the inclined cables.

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Zagyapan, M., C. A. Fairfield, A. Sibbald, and A. Bensalem. "Measurement of Granular Fill Compaction Using Low Frequency Vibration Testing." Journal of Low Frequency Noise, Vibration and Active Control 19, no. 3 (September 2000): 151–69. http://dx.doi.org/10.1260/0263092001492912.

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This paper describes the use of an instrumented impact hammer test for density measurement in a granular soil (Specification for Highway Works Type 1 fill) whilst monitoring the performance of vibro-tamper compaction. A 3–D finite element model was also used as a predictor. The effect of varying key material properties was studied. An increase in the soil's modulus of elasticity resulted in higher natural frequencies. An impact hammer, fitted with a force transducer, was used to excite the soil whose response was measured by accelerometer and analysed in both time and frequency domains. The change in natural frequencies of the modes of soil vibration was observed after each pass of a vibro-tamper. A sudden increase in natural frequencies was observed after the first pass; this effect reduced with compaction. Shear wave velocities were used to calculate a low strain modulus of elasticity and a correlation was established with the modulus of elasticity derived from Clegg hammer impact values. The same type of tests were applied to understand the field attenuation characteristics of Type 1 fill. There was a slight decrease in the maximum amplitude of the shear waves with increasing compaction; high attenuation of shear waves was also noted.

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Li, Dongwei, and Juhong Fan. "A Study of Mechanical Property of Artificial Frozen Clay under Dynamic Load." Advances in Civil Engineering 2018 (2018): 1–8. http://dx.doi.org/10.1155/2018/5392641.

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To determine the mechanical properties of artificial frozen clay under dynamic load, 81 triaxial shear tests were carried out for artificial frozen clay at different temperatures, amplitudes, frequencies, and precompressions and three kinds of testing conditions. The change laws of the dynamic modulus of elasticity, maximum dynamic shear modulus, dynamic damping ratio, and strain rate were determined. These results can guide future research on the mechanical mechanisms of frozen soil, providing both theoretical and practical significance.

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SHEKAR, S., and P. VENUGOPAL REDDY. "ELASTICITY STUDIES OF SOME Bi-Pb-Sr-Ca-Cu-O HIGH-Tc SUPERCONDUCTING MATERIALS." Modern Physics Letters B 07, no. 13n14 (June 20, 1993): 935–47. http://dx.doi.org/10.1142/s0217984993000941.

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Longitudinal and shear wave velocities of lead-substituted Bi-Sr-Ca-Cu-O (2223) super-conducting materials prepared by the three-step matrix solid state reaction method have been measured by the pulse transmission technique. Using the data, several elasticity parameters like Young’s modulus, rigidity modulus, Poisson’s ratio, Debye temperature, etc. have been evaluated. Variation of elasticity parameters with lead concentration has been explained in terms of binding forces between various atoms. It has been observed that these materials are behaving like any other oxide materials.

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Stasiak, M. "Determination of elastic parameters of grain with oedometric and acoustic methods." Research in Agricultural Engineering 49, No. 2 (February 8, 2012): 56–60. http://dx.doi.org/10.17221/4953-rae.

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Values of modulus of elasticity E and Poisson’s ratio   were determined with two methods adopted from geotechnique. First approach used was a method proposed by Sawicki (1994). This type of examination was applied to estimate values of E and v for wheat and rapeseed beddings for five levels of moisture content ranging from 6% to 20%. Modulus of elasticity E of wheat was found to decrease with an increase in moisture content. With the second method values of E were determined based on measurement of shear wave velocity. Tests were performed for bedding of wheat and rapeseed under equilibrium moisture content. Values of modulus of elasticity were found to depend of hydrostatic pressure and were higher then those determined in uniaxial compression test.

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Güler, E., and M. Güler. "Geometry Optimization Calculations for the Elasticity of Gold at High Pressure." Advances in Materials Science and Engineering 2013 (2013): 1–5. http://dx.doi.org/10.1155/2013/525673.

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We present embedded atom method based geometry optimization aspects of pressure effect on some elastic and mechanical properties of gold. During study, we determined the pressure dependency of equilibrium volume, typical cubic elastic constants, bulk modulus, shear modulus, young modulus, and elastic wave velocities of the considered metal with varying pressure between 0 GPa and 1000 GPa. Finally, we carried out a benchmark between our results and other available theoretical calculations and experimental data. The results of the study mutually agree with the previous findings and provide a deeper outlook for high pressure behavior of the studied metal.

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Gordan, Behrouz, Azlan Adnan, and Mariyana A. K. Aida. "Soil Saturated Simulation in Embankment during Strong Earthquake by Effect of Elasticity Modulus." Modelling and Simulation in Engineering 2014 (2014): 1–7. http://dx.doi.org/10.1155/2014/191460.

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The dynamic analysis process was started after failure in some embankments during an earthquake. In this context, maximum displacement was reported at the crest based on interaction between structure and reservoir. This paper investigates the dynamic behavior of short embankment on soft soil. For this purpose, numerical analysis was carried out using ANSYS13 program based on finite-element method. Simulated models were vibrated by strong earthquake, so the peak ground acceleration (PGA) and duration were 0.65 g and 5.02 seconds, respectively. The comparison results were discussed in key points of plane strain analysis based on modulus ratio between saturated embankment and foundation. As concluded, the modulus ratio between 0.53 and 0.66 led to having a minimum value of horizontal displacement, relative displacement in vertical direction, and shear stress. Consequently, the shear stress was increased while the modulus ratio was decreased. Finally, to avoid more rigidity in the embankment on the soft soil, optimum modulus ratio was recommended at 0.66 in order to reduce the probabilistic of body cracks at the crest with respect to homogeneous behavior during an earthquake.

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Kleinberg, AS, RL Meltzer, JR Schroeder, B. Benzing, MB Vieth, K. Greene, MT Pravitz, and S. Cheng. "Test Method for Evaluation of Shear Modulus and Modulus of Elasticity of Laminated Anisotropic Composite Materials." Journal of Testing and Evaluation 13, no. 5 (1985): 387. http://dx.doi.org/10.1520/jte10968j.

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Novotna, P., M. Houska, V. Sopr, H. Valentova, and P. Stern. "Vliv smykové viskozity a elasticity na senzorickou viskozitu modelových kapalných potravin." Czech Journal of Food Sciences 17, No. 1 (January 1, 1999): 23–30. http://dx.doi.org/10.17221/10016-cjfs.

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The shear flow rheological properties of sugar solutions (70% w/w concentration) modified by different cellulose derivatives have been measured. Thickeners were expected to cause the viscoelastic behaviour of the resulting sol ution. Therefore, the elastic rheological parameters were measured by oscillatory shear technique (phase angle, elastic modulus) and also the first normal stress difference N<sub>1</sub>. The increase of thickener concen tration caused a moderate increase of non-Newtonian behaviour in the shear flow. The sensory viscosity (ra nged between 0 and 100%) was evaluated by five different methods - as an effort for stirring with teaspoon, time for flowing down the spoon, slurping from spoon, compression between tongue and palate and swallowing. The influence of shear viscosity and first normal difference on sensory viscosity was tested. Correlation procedu re between change of sensory viscosity .tlSE and change of shear viscosity .tlJ.Iz showed that only for swallowing there is a statistically evident dependence. The correlation between change of sensory viscosity t.SE and first normal stress difference N<sub>1</sub> is not statistically evident. For all the methods of sensory evaluation the dependence between these parameters is only weak and indirect (with increasing normal stress difference the sensory viscosity is decreasing).

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Liu, Y., and A. W. C. Lee. "Selected Properties of Parallel Strand Lumber Made from Southern Pine and Yellow-Poplar." Holzforschung 57, no. 2 (February 27, 2003): 207–12. http://dx.doi.org/10.1515/hf.2003.030.

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Summary This study was conducted to explore basic physical and mechanical properties of parallel strand lumber (PSL) made exclusively from southern pine and yellow-poplar, respectively, and to examine their relationships using statistical analysis. Small specimens were prepared from commercial southern pine PSL and yellow-poplar PSL billets and tested for specific gravity, moisture content, dimensional stability, bending properties, shear strength and compressive strength. Results indicate average specific gravity of southern pine PSL is higher than that of yellow-poplar PSL, while their average moisture content and dimensional stability are very similar. Southern pine PSL has higher average modulus of elasticity but lower average modulus of rupture than yellow-poplar PSL. While average longitudinal shear strength does not exhibit differences between southern pine PSL and yellow-poplar PSL, average compressive strength of southern pine PSL is higher than that of yellow-poplar PSL. There are positive correlations among modulus of elasticity, modulus of rupture and specific gravity. PSL improves some properties of solid wood from which PSL is made.

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Bedewi, Mohamed A., Ayman A. Elsifey, Ayman K. Saleh, and Tariq Alfaifi. "Shear wave elastography of the knee menisci." Journal of International Medical Research 48, no. 11 (November 2020): 030006052097604. http://dx.doi.org/10.1177/0300060520976048.

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Objective To determine the ability of shear wave elastography to measure the stiffness of the knee menisci in healthy adults. Methods This observational cross-sectional study evaluated knee joints in healthy adults. Shear wave elastography was used to evaluate the anterior horn of the medial menisci bilaterally. The correlations between the mean elasticity bilaterally and age, weight, height and body mass index (BMI) were calculated using Pearson’s correlation coefficient test. Results A total of 34 knee joints in 17 healthy subjects were evaluated. The mean ± SD shear elastic modulus of the anterior horn of the right medial meniscus was 24.86 ± 6.35 kPa and of the anterior horn of the left medial meniscus was 23.86 ± 4.49 kPa. A significant inverse correlation was observed between the right medial meniscus elasticity and height. Other demographic factors showed no significant relationship to the anterior horn of the right medial meniscus elasticity. A significant inverse correlation was observed between the anterior horn of the left medial meniscus elasticity and age, while a significant positive correlation was observed between left medial meniscus elasticity and BMI. Conclusion These preliminary results suggest that shear wave elastography could be a potential tool to aid in studying the stiffness of the knee menisci.

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Volokh, K. Y. "Nonlinear Elasticity for Modeling Fracture of Isotropic Brittle Solids." Journal of Applied Mechanics 71, no. 1 (January 1, 2004): 141–43. http://dx.doi.org/10.1115/1.1636795.

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A softening hyperelastic continuum model is proposed for analysis of brittle fracture. Isotropic material is characterized by two standard parameters—shear and bulk modulus—and an additional parameter of the volumetric separation work. The model can be considered as a volumetric generalization of the concept of the cohesive surface. The meaning of the proposed constitutive equations is clarified by the examples of simple shear and hydrostatic pressure. It is emphasized that the proposed constitutive model includes only smooth functions and the necessary computational techniques are those of nonlinear elasticity.

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André L., Christoforo, Icimoto Felipe H., Fernandes Caio Victor, Fiorelli Juliano, Negrão João, and Lahr Francisco A. Rocco. "Shear and Longitudinal Modulus of Elasticity in Structural Profiled Round Timber Beams." International Journal of Materials Engineering 3, no. 4 (August 1, 2013): 87–91. http://dx.doi.org/10.5923/j.ijme.20130304.04.

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Zangiácomo, André Luiz, André Luis Christoforo, and Francisco Antonio Rocco Lahr. "Shear and longitudinal modulus of elasticity in Corymbia citriodora round timber beams." Revista Vértices 15, no. 1 (2013): 63–68. http://dx.doi.org/10.5935/1809-2667.20130006.

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Kang, Yu Bong, T. Oida, Duk Young Jung, A. Fukuma, T. Azuma, J. Okamoto, O. Takizawa, T. Matsuda, and Sadami Tsutsumi. "Non-Invasive Measurement of In-Vivo Elasticity of Skeletal Muscles with MR-Elastography." Key Engineering Materials 342-343 (July 2007): 901–4. http://dx.doi.org/10.4028/www.scientific.net/kem.342-343.901.

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In order to evaluate the mechanical properties of the human skeletal muscles, the elasticity and viscosity of the human calf muscles were measured with Magnetic Resonance Elastography (MRE). MRE is a novel method to measure the mechanical properties of living soft tissues in vivo quantitatively by observing the strain waves propagated in the object. In this study, the shear modulus and viscosity coefficient were measured with MRE. The shear modulus was 3.7 kPa in relaxed state, and increased with increasing the muscle forces. Interestingly, the viscosity was changed with the vibration frequency applied to the muscles, that was 4.5 Pa·s at 100Hz vibration and 2.4 Pa·s at 200Hz vibration. This shows clearly the visco-elastic property.

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Li, Guan-Nan, Zhi-Qian Chen, Yu-Ming Lu, Meng Hu, Li-Na Jiao, and Hao-Ting Zhao. "Elasticity, slowness, thermal conductivity and the anisotropies in the Mn3Cu1−xGexN compounds." International Journal of Modern Physics B 32, no. 07 (March 5, 2018): 1850071. http://dx.doi.org/10.1142/s0217979218500716.

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We perform the first-principles to systematically investigate the elastic properties, minimum thermal conductivity and anisotropy of the negative thermal expansion compounds Mn3Cu[Formula: see text]Ge[Formula: see text]N. The elastic constant, bulk modulus, shear modulus, Young’s modulus and Poisson ratio are calculated for all the compounds. The results of the elastic constant indicate that all the compounds are mechanically stable and the doped Ge can adjust the ductile character of the compounds. According to the values of the percent ratio of the elastic anisotropy A[Formula: see text], A[Formula: see text] and A[Formula: see text], shear anisotropic factors A1, A2 and A3, all the Mn3Cu[Formula: see text]Ge[Formula: see text]N compounds are elastic anisotropy. The three-dimensional diagrams of elastic moduli in space also show that all the compounds are elastic anisotropy. In addition, the acoustic wave speed, slowness, minimum thermal conductivity and Debye temperature are also calculated. When the ratio of content for Cu and Ge arrived to 1:1, the compound has the lowest thermal conductivity and the highest Debye temperature.

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Conrad, Nathaniel, Tynan Kennedy, Deborah K. Fygenson, and Omar A. Saleh. "Increasing valence pushes DNA nanostar networks to the isostatic point." Proceedings of the National Academy of Sciences 116, no. 15 (March 26, 2019): 7238–43. http://dx.doi.org/10.1073/pnas.1819683116.

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The classic picture of soft material mechanics is that of rubber elasticity, in which material modulus is related to the entropic elasticity of flexible polymeric linkers. The rubber model, however, largely ignores the role of valence (i.e., the number of network chains emanating from a junction). Recent work predicts that valence, and particularly the Maxwell isostatic point, plays a key role in determining the mechanics of semiflexible polymer networks. Here, we report a series of experiments confirming the prominent role of valence in determining the mechanics of a model system. The system is based on DNA nanostars (DNAns): multiarmed, self-assembled nanostructures that form thermoreversible equilibrium gels through base pair-controlled cross-linking. We measure the linear and nonlinear elastic properties of these gels as a function of DNAns arm number, f, and concentration [DNAns]. We find that, as f increases from three to six, the gel’s high-frequency plateau modulus strongly increases, and its dependence on [DNAns] transitions from nonlinear to linear. Additionally, higher-valence gels exhibit less strain hardening, indicating that they have less configurational freedom. Minimal strain hardening and linear dependence of shear modulus on concentration at high f are consistent with predictions for isostatic systems. Evident strain hardening and nonlinear concentration dependence of shear modulus suggest that the low-f networks are subisostatic and have a transient, potentially fractal percolated structure. Overall, our observations indicate that network elasticity is sensitive both to entropic elasticity of network chains and to junction valence, with an apparent isostatic point 5<fc≤6 in agreement with the Maxwell prediction.

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Malkin, Alexander Ya, Valery G. Kulichikhin, Anton V. Mityukov, and Sergey V. Kotomin. "Deformation Properties of Concentrated Metal-in-Polymer Suspensions under Superimposed Compression and Shear." Polymers 12, no. 5 (May 2, 2020): 1038. http://dx.doi.org/10.3390/polym12051038.

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Concentrated metal-in-polymer suspensions (55 vol.% and 60 vol.%) of aluminum powder dispersed in low molecular weight polyethylene glycol) demonstrate elastoplastic properties under compression and shear. The rheological behavior of concentrated suspensions was studied in a rotational rheometer with uniaxial compression (squeezing), as well as shearing superimposed on compression. At a high metal concentration, the elasticity of the material strongly increases under strain, compared with the plasticity. The elastic compression modulus increases with the growth of normal stress. Changes in the shear modulus depend on both normal and shear stresses. At a low compression force, the shear modulus is only slightly dependent on the shear stress. However, high compression stress leads to a decrease in the shear modulus by several orders with the growth of the shear stress. The decrease in the modulus seems to be rather unusual for compacted matter. This phenomenon could be explained by the rearrangement of the specific organization of the suspension under compression, leading to the creation of inhomogeneous structures and their displacement at flow, accompanied by wall slip. The obtained set of rheological characteristics of highly loaded metal-in-polymer suspensions is the basis for understanding the behavior of such systems in the powder injection molding process.

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Corigliano, Pasqualino, Vincenzo Crupi, Serena Bertagna, and Alberto Marinò. "Bio-Based Adhesives for Wooden Boatbuilding." Journal of Marine Science and Engineering 9, no. 1 (December 30, 2020): 28. http://dx.doi.org/10.3390/jmse9010028.

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The aim of the present investigation was to assess the behaviour of strip-planked parts by comparing wooden specimens glued using two different bio-based adhesives with wooden specimens glued using a conventional epoxy resin generally used in boatbuilding. Experimental tests in accordance with UNI EN standards were performed in order to evaluate mechanical properties such as tensile strength, shear strength, elastic modulus and shear modulus. In addition, compression shear tests were performed in order to assess the shear modulus of the adhesives. The obtained results demonstrate that the mechanical properties of the investigated bio-based adhesives are comparable to, and sometimes better than, the conventional epoxy resin. Moreover, the experimental results give useful information for the design of wooden boats when the strip-planking process is used. Furthermore, a new procedure to assess the shear modulus of elasticity and shear strength, using the application of compression loadings, was proposed. The results were compared to standard lap-joint tests and showed even lower dispersion. Consequently, the testing procedure proposed by the authors is valid to assess shear properties under compression loading, and it can be applied in most laboratories since it involves the use of common testing devices.

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Quan, Hong Zhu. "Study on Strength and Durability of Concrete Containing Recycled Coarse Aggregate Manufactured with Various Method." Advanced Materials Research 287-290 (July 2011): 1015–18. http://dx.doi.org/10.4028/www.scientific.net/amr.287-290.1015.

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This paper presents the results of experimental study on the effects of adhered mortar content on strengths and durability of concrete. Compressive, tensile and shear strengths, modulus of elasticity, drying shrinkage and carbonation were tested on concrete mixtures with the water cement ratio of 0.43, 0.50 and 0.60 using 3 kinds recycled coarse aggregate and a riversand. The test results of concrete indicated higher compressive, tensile amd shear strengths and higher modulus of elasticity for concrete using recycled corase aggregate with lower adhered mortar content, lower absorption and higher specific gravity. Recycled aggregate with higher adhered mortar content also showed significunt adverse effects on drying shrinkage and carbonation. In conclusion, the upper limit of adhered mortar content of coarse recycled aggregate to keep up the quality of aggregate and concrete equal to natural coarse aggregate and those concrete is considered to be 15%.

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Kumamoto, Tsuneo, Toshiaki Seko, Ryo Matsuda, and Sayo Miura. "Repeated standing back extension exercise: Influence on muscle shear modulus change after lumbodorsal muscle fatigue." Work 68, no. 4 (April 27, 2021): 1229–37. http://dx.doi.org/10.3233/wor-213452.

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BACKGROUND: In low back pain, multifidus muscle fibers reportedly exhibit increased stiffness. Low back pain was associated with lumbodorsal muscle fatigue. There is no report of using shear modulus to verify the mechanism of an immediate effect of exercise on low back pain. Here, temporary lumbodorsal muscle fatigue was created, simulating fatigue-related nonspecific low back pain. OBJECTIVE: To assess the effect of standing back extension exercise on fatigued lumbodorsal muscle based on the results of multifidus muscle elasticity measured using shear wave elastography. METHODS: Thirty-three healthy subjects were randomly divided into three groups. The subjects performed the Biering-Sorensen test as the fatigue-task of the lumbodorsal muscle before the standing back extension exercise. The fatigue-exercise group exercised five sets after completing the fatigue-task. The fatigue-non-exercise group remained standing for the same duration as the fatigue-exercise group without doing the exercise after the fatigue-task. The non-fatigue-exercise group exercised five sets of without performing the fatigue-task. As intra-group and inter-group factors, the shear modulus of the multifidus muscle was compared before and after the exercise. RESULTS: The shear modulus of the multifidus muscle after the standing back extension exercise was significantly lower in the fatigue-exercise group, and no significant decrease was observed in the fatigue-non-exercise and non-fatigue-exercise group. CONCLUSIONS: The standing back extension exercise improved the shear modulus of the fatigued multifidus muscle. Therefore, it was suggested that the change in the elasticity of fatigued muscle might lead to the prevention of low back pain caused by muscle fatigue.

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Nordez, Antoine, and François Hug. "Muscle shear elastic modulus measured using supersonic shear imaging is highly related to muscle activity level." Journal of Applied Physiology 108, no. 5 (May 2010): 1389–94. http://dx.doi.org/10.1152/japplphysiol.01323.2009.

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This pilot study was designed to determine whether the shear elastic modulus measured using supersonic shear imaging can be used to accurately estimate muscle activity level. Using direct visual feedback of torque, six healthy subjects were asked to perform two incremental isometric elbow flexions, consisting of linear torque ramps of 30 s from 0 to 40% of maximal voluntary contraction. Both electromyographic (EMG) activity and shear elastic modulus were continuously measured in the biceps brachii during the two ramps. There was significant linear regression ( P < 0.001) between shear elastic modulus and EMG activity level for both ramps of all six subjects ( R2 = 0.94 ± 0.05, ranging from 0.82 to 0.98). Good repeatability was found for shear elastic modulus estimated at both 3% ( trial 1: 21.7 ± 6.7 kPa; trial 2: 23.2 ± 7.2 kPa, intraclass correlation coefficient = 0.89, standard error in measurement = 2.3 kPa, coefficient of variation = 12.7%) and 7% ( trial 1: 42.6 ± 14.1 kPa; trial 2: 44.8 ± 15.8 kPa, intraclass correlation coefficient = 0.94, standard error in measurement = 3.7 kPa, coefficient of variation = 7.1%) of maximal EMG activity. The shear elastic modulus estimated at both 3 and 7% of maximal EMG activity was not significantly different ( P > 0.05) between the two trials. These results confirm our hypothesis that the use of supersonic shear imaging greatly improves the correlation between muscle shear elastic modulus and EMG activity level. Due to the nonlinearity of muscle mechanical properties, the muscle elasticity should be linked to the muscle stress. Therefore, the present study represents a first step in attempting to show that supersonic shear imaging can be used to indirectly estimate muscle stress.

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Zaccone, Alessio, and Kostya Trachenko. "Explaining the low-frequency shear elasticity of confined liquids." Proceedings of the National Academy of Sciences 117, no. 33 (August 3, 2020): 19653–55. http://dx.doi.org/10.1073/pnas.2010787117.

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Experimental observations of unexpected shear rigidity in confined liquids, on very low frequency scales on the order of 0.01 to 0.1 Hz, call into question our basic understanding of the elasticity of liquids and have posed a challenge to theoretical models of the liquid state ever since. Here we combine the nonaffine theory of lattice dynamics valid for disordered condensed matter systems with the Frenkel theory of the liquid state. The emerging framework shows that applying confinement to a liquid can effectively suppress the low-frequency modes that are responsible for nonaffine soft mechanical response, thus leading to an effective increase of the liquid shear rigidity. The theory successfully predicts the scaling lawG′∼L−3for the low-frequency shear modulus of liquids as a function of the confinement length L, in agreement with experimental results, and provides the basis for a more general description of the elasticity of liquids across different time and length scales.

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PARK, YONG SUNG, and PHILIP L. F. LIU. "Oscillatory pipe flows of a yield-stress fluid." Journal of Fluid Mechanics 658 (June 10, 2010): 211–28. http://dx.doi.org/10.1017/s0022112010001667.

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Oscillatory pipe flows of aqueous Carbopol solutions are investigated both experimentally and analytically. Using the PIV technique, the velocity profiles are measured and compared with the numerical solutions based on an elasto-viscoplastic rheological model, in which an elastic spring is serially connected to a regularized Bingham viscoplastic model. The rheological parameters, such as shear modulus of elasticity, yield stress and viscosity, are estimated from steady-shear measurements. Good agreement between the experiments and the model results is observed. It is apparent that the elasticity plays an important role in the unsteady flows of the soft yield-stress fluid studied herein.

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Ozer, Halil, and Ozkan Oz. "Joint Stress Optimization by the Hybrid Adhesive Lap Joint." Advanced Materials Research 445 (January 2012): 1000–1004. http://dx.doi.org/10.4028/www.scientific.net/amr.445.1000.

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Hybrid adhesive joint is an alternative stress reduction technique for the adhesively bonded joints. Hybrid adhesive means that it is used dual adhesives in the overlap region. Adhesive having high modulus of elasticity should be located in the middle of the bondline and the other adhesive having low modulus of elasticity at the ends. In this study, the effect of the hybrid adhesive bondline on the distributions of the peeling, shear and von Mises stress components at the single lap joint were investigated by using three-dimensional finite element model. The results show that the considered stress components can be optimized by using hybrid adhesive joint.

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Pang, Yu Yang, Pu Zhang, Dan Ying Gao, and Fei Mo. "The Effects on Tensile Properties of Different Winding Way on GFRP Bar." Applied Mechanics and Materials 438-439 (October 2013): 357–60. http://dx.doi.org/10.4028/www.scientific.net/amm.438-439.357.

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The influence of different surface forms on GFRP reinforcement mainly manifest in bonding between reinforcement materials and concrete, especially when the GFRP bars are used in slope, the form of the surface of GFRP bar will affect reinforced materials torsion and shear properties directly. This article made some tensile tests on several different surface forms of GFRP reinforcement, and learned that the form of the surface wound of GFRP bar make the influence on tensile strength, ultimate elongation and modulus of elasticity. Test results show that the surface of the winding way will affect on the tensile strength, ultimate elongation and modulus of elasticity of GFRP bar.

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Journal articles on the topic 'Shear Modulus of Elasticity'

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