Journal articles: 'Static elastic modulus'

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Gao, Xiao Peng, and Fu Shun Liu. "The Study of Ultrasonic Dynamic Elastic Modulus of TiNiFe Shape Memory Alloy in Heating Process." Advanced Materials Research 79-82 (August 2009): 1699–702. http://dx.doi.org/10.4028/www.scientific.net/amr.79-82.1699.

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The phase transformation characteristics, the dynamic elastic modulus and the static tensile elastic modulus of Ti50Ni47.5Fe2.5 alloy were investigated. It is found that, the two mutations in the dynamic elastic modulus is caused by reverse martensite phase transformation and austenite phase transformation respectively; Static tensile test can not reflect the intrinsic elastic modulus when the test temperature is close to martensite transformation temperature(Ms). The static elastic modulus and the dynamic elastic modulus have the same trend when the test temperature is enough higher than Ms.

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Sone, Hiroki, and Mark D. Zoback. "Mechanical properties of shale-gas reservoir rocks — Part 1: Static and dynamic elastic properties and anisotropy." GEOPHYSICS 78, no. 5 (September 1, 2013): D381—D392. http://dx.doi.org/10.1190/geo2013-0050.1.

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Understanding the controls on the elastic properties of reservoir rocks is crucial for exploration and successful production from hydrocarbon reservoirs. We studied the static and dynamic elastic properties of shale gas reservoir rocks from Barnett, Haynesville, Eagle Ford, and Fort St. John shales through laboratory experiments. The elastic properties of these rocks vary significantly between reservoirs (and within a reservoir) due to the wide variety of material composition and microstructures exhibited by these organic-rich shales. The static (Young’s modulus) and dynamic (P- and S-wave moduli) elastic parameters generally decrease monotonically with the clay plus kerogen content. The variation of the elastic moduli can be explained in terms of the Voigt and Reuss limits predicted by end-member components. However, the elastic properties of the shales are strongly anisotropic and the degree of anisotropy was found to correlate with the amount of clay and organic content as well as the shale fabric. We also found that the first-loading static modulus was, on average, approximately 20% lower than the unloading/reloading static modulus. Because the unloading/reloading static modulus compares quite well to the dynamic modulus in the rocks studied, comparing static and dynamic moduli can vary considerably depending on which static modulus is used.

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Wang, Jie Jun, Yan Ge Liu, and Di Yang Xia. "Study on Vibration-Based Detection Methods for Determining the Elastic Modulus of Glulam Beams." Applied Mechanics and Materials 847 (July 2016): 463–68. http://dx.doi.org/10.4028/www.scientific.net/amm.847.463.

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This paper presents the vibration test method of the elastic modulus of glulam beams. Under the condition of simply supported, the elastic modulus of glulam beams is tested based on the vibration method. Compared with the static modulus tested by static load test and the natural frequency tested by finite element method, vibration-based detection method is proved to be feasible and accurate in measuring the elastic modulus of glued laminated beams.

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Gong, Fei, Bangrang Di, Jianxin Wei, Pinbo Ding, He Tian, and Jianqiang Han. "A study of the anisotropic static and dynamic elastic properties of transversely isotropic rocks." GEOPHYSICS 84, no. 6 (November 1, 2019): C281—C293. http://dx.doi.org/10.1190/geo2018-0590.1.

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The elastic properties of rock are major factors affecting hydraulic fracturing. Static elastic properties can be estimated using geomechanical laboratory tests, whereas dynamic properties can be estimated from elastic-wave velocity and rock density. We prepared two synthetic shales containing different clay minerals and one natural shale and focused on the elastic properties for the full tensor of elasticity and their anisotropy. The static and dynamic properties of these dry samples were obtained based on triaxial tests during loading and unloading. The results suggest that the synthetic and natural shale indicate high similarity in the static and dynamic properties. The dynamic Young’s modulus and Poisson’s ratio increase with increasing axial stress during loading and unloading. For the static properties, the static Poisson’s ratio increases with axial stress during loading and unloading. However, differences exist between the static and dynamic Young’s moduli during loading, with the static Young’s modulus decreases with the increasing axial stress at a high stress level. In addition, the static Young’s modulus is consistently lower than the dynamic Young’s modulus during loading and unloading, but the static Poisson’s ratio is larger or smaller than the dynamic Poisson’s ratio. During loading and unloading, there could be approximately a 30% difference when estimating static elastic properties from the static-dynamic relations, depending on which static moduli are used. Furthermore, the static and dynamic properties of the samples are strongly anisotropic, and the anisotropy of elastic properties is sensitive to the axial stress and the clay minerals.

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Choubane, Bouzid, Chung-Lung Wu, and Mang Tia. "Coarse Aggregate Effects on Elastic Moduli of Concrete." Transportation Research Record: Journal of the Transportation Research Board 1547, no. 1 (January 1996): 29–34. http://dx.doi.org/10.1177/0361198196154700105.

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The results of a laboratory testing program carried out to investigate the effect of coarse aggregate types on the elastic modulus of typical pavement concretes are presented. The elastic modulus was determined in both flexure and compression using static and dynamic means. Three different mixes, made using three different aggregates, were compared. The water-cement ratio was kept at 0.53 throughout the test program. The results showed that within the tested range, the aggregate type significantly affected the studied properties of concrete. Calera aggregate (a dense limestone) with its rough-textured surface and angular shape produced a concrete with higher strength and stiffness than those of concretes made with Brooksville aggregate (a porous limestone) and river gravel. In addition, the measured dynamic modulus in compression was significantly different from that in flexure. Also, in flexure, the dynamic modulus was higher than the static modulus by an average of 23 percent, whereas in compression, the dynamic modulus appeared to be in the same range as the static modulus. The change in frequency from 1 to 7 Hz did not have a significant influence on the dynamic modulus.

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Qiu, Yan, Yi Wang Bao, Xiao Gen Liu, Xiu Fang Wang, and Kun Ming Li. "Comparison and Relative Error of Elastic Modulus in Glass Measured by Three Test Techniques." Key Engineering Materials 434-435 (March 2010): 209–13. http://dx.doi.org/10.4028/www.scientific.net/kem.434-435.209.

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Elastic modulus of glass was measured using static method, dynamic method and Vickers indentation technique, respectively. The residual indent of Vickers indentation is analyzed to estimate the elastic modulus, using conventional hardness tester without load-depth curve. The modulus and hardness of glass are determined by load, deformation and residual semi-angle of the indent. The result is compared with the modulus obtained by conventional dynamic and static methods. It was shown that the modulus measured by dynamic method provides the highest value and the modulus obtained by indentation technique is between the values of dynamic modulus and static modulus. The result also shows that the modulus measured by dynamic method has very stable value and that measured by bending method has the lowest value. The modulus obtained in indentation tests shows relatively greater scatter.

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Sitharam, T. G., M. Ramulu, and V. B. Maji. "Static and Dynamic Elastic Modulus of Jointed Rock Mass." International Journal of Geotechnical Earthquake Engineering 1, no. 2 (July 2010): 89–112. http://dx.doi.org/10.4018/jgee.2010070107.

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In this paper the compressive strength/elastic modulus of the jointed rock mass was estimated as a function of intact rock strength/modulus and joint factor. The joint factor reflects the combined effect of joint frequency, joint inclination and joint strength. Therefore, having known the intact rock properties and the joint factor, jointed rock properties can be estimated. The test results indicated that the rock mass strength decreases with an increase in the joint frequency and a sharp transition was observed from brittle to ductile behaviour with an increase in the number of joints. It was also found that the rocks with planar anisotropy exhibit the highest strength in the direction perpendicular to the anisotropy and the lowest at an inclination of 30o-45o in jointed samples. The anisotropy of the specimen influences the dynamic elastic modulus more than the static elastic modulus. The results were also compared well with the published works of different authors for different type of rocks.

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Panesar, D. K., and S. E. Chidiac. "Ultrasonic pulse velocity for determining the early age properties of dry-cast concrete containing ground granulated blast-furnace slag." Canadian Journal of Civil Engineering 34, no. 5 (May 1, 2007): 682–85. http://dx.doi.org/10.1139/l07-039.

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This study evaluates the potential use of ultrasonic pulse velocity (UPV) for determining the early age compressive strength of dry-cast concrete containing varying percentages of ground granulated blast-furnace slag (GGBFS). The proposed approach includes computing the dynamic elastic modulus from UPV measurements, evaluating the static elastic modulus from experimentally measured dynamic-to-static elastic modulus ratios, and determining the compressive strength from the static elastic modulus using formulae suggested in ACI-363. The early age strengths of dry-cast concrete containing varying amount of GGBFS, which are determined using UPV measurements, are in good agreement with the measured strength. The evaluation is also extended to include five datasets reported in published literature for concrete containing varying types and amounts of mineral admixtures. Key words: concrete, compressive strength, dry cast, early age properties, ground granulated blast-furnace slag (GGBFS), ultrasonic pulse velocity (UPV).

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Kurakina, Elena, Sergej Evtyukov, and Jaroslav Rajczyk. "Diagnostic assessment of an impact of static and dynamic vehicle loads on covering of roadway." MATEC Web of Conferences 334 (2021): 01014. http://dx.doi.org/10.1051/matecconf/202133401014.

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The article presents diagnostic possibilities for testing covering of roadway through dynamic and static loading units. The article presents features, advantages and principal characteristics of the equipment: die unit, Dina-3M, UDN-NK, Dynatest unit. The main parameters of the dynamic impact units. The article also presents results of tests by dynamic and static loading, defines «flexural bowls», elastic module and the coefficients of reduction of the elastic modulus to the static modulus.

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Nakamura, Masatoshi, Shigeru Sato, Ryosuke Kiyono, Nobushige Takahashi, and Tomoichi Yoshida. "Effect of Rest Duration Between Static Stretching on Passive Stiffness of Medial Gastrocnemius Muscle In Vivo." Journal of Sport Rehabilitation 29, no. 5 (July 1, 2020): 578–82. http://dx.doi.org/10.1123/jsr.2018-0376.

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Context: In clinical and sports settings, static stretching (SS) is usually performed to increase range of motion (ROM) and decrease passive muscle stiffness. Recently, the shear elastic modulus was measured by ultrasonic shear wave elastography as an index of muscle stiffness. Previous studies reported that the shear elastic modulus measured by ultrasound shear wave elastography decreased after SS, and the effects of SS on shear elastic modulus were likely affected by rest duration between sets of SS. Objective: To investigate the acute effects of SS with different rest durations on ROM and shear elastic modulus of gastrocnemius and to clarify whether the rest duration between sets of SS decreases the shear elastic modulus. Design: A randomized, repeated-measures experimental design. Setting: University laboratory. Participants: Sixteen healthy males volunteered to participate in the study (age 21.3 [0.8] y; height 171.8 [5.1] cm; weight 63.1 [4.5] kg). Main Outcome Measures: Each participant underwent 3 different rest interval durations during SS (ie, long rest duration: 90 s; normal rest duration: 30 s; and short rest duration: 10 s). This SS technique was repeated 10 times, thus lasting a total of 300 seconds with different rest durations in each protocol. The dorsiflexion ROM and shear elastic modulus were measured before and after SS. Results: Our results revealed that dorsiflexion ROM and shear elastic modulus were changed after 300-second SS; however, no effects of the rest duration between sets of SS were observed. Conclusions: In terms of decreasing the shear elastic modulus, clinicians and coaches should not focus on the rest duration when SS intervention is performed.

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Yin, Shui Ping, and Min Yu. "Dynamic Visco-Elastic Properties of Polycarbonate (PC) under Static and Dynamic Load." Advanced Materials Research 146-147 (October 2010): 1090–93. http://dx.doi.org/10.4028/www.scientific.net/amr.146-147.1090.

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The purpose of this work was to investigate the effects of pre-load static load and dynamic load on the visco-elastic in polycarbonate. In the paper, static-dynamic sweep experiment of polycarbonate was performed on EPLEXOR 500N, which was manufactured by GABO of Germany. The variation laws of storage modulus, loss modulus and loss tangent as changing dynamic load in a large range were systematically analyzed and the spectral characteristics of dynamic-viscoelastic under static-dynamic loads were obtained. The experiment results on dynamic visco-elastic under the high load shows that the load effects on dynamic visco-elasticity of polycarbonate performing on the changing of the dynamic visco-elastic parameters, storage modulus become lager with the increasing of static load and decreasing with the increasing of dynamic load, while loss tangent decreases with the increasing of dynamic load and varies in a more complicated pattern as the increasing of static load.

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Wang, Yang, De-Hua Han, Hui Li, Luanxiao Zhao, Jiali Ren, and Yonghao Zhang. "A comparative study of the stress-dependence of dynamic and static moduli for sandstones." GEOPHYSICS 85, no. 4 (April 30, 2020): MR179—MR190. http://dx.doi.org/10.1190/geo2019-0335.1.

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Understanding the differences between the static and dynamic elastic moduli of reservoir rocks is essential for the successful exploration and production of hydrocarbon reservoirs. However, the controlling factors on the dynamic-static discrepancy for sandstones remain ambiguous. Consequently, we have purposely selected three outcrop sandstone samples with large porosity contrast to investigate the effects of the stress state, magnitude, and load-unload history on the dynamic and static moduli through laboratory measurements. The results suggest that the dynamic moduli are systematically larger than the static moduli at almost any hydrostatic or deviatoric stress magnitude. In contrast, the static moduli are much more sensitive to the stress variations than the dynamic ones, leading to the decreasing dynamic-static difference upon hydrostatic loading and the increasing dynamic-static difference upon deviatoric loading. When the maximum stress in a cycle is initially reversed, the dynamic-static ratio tends to approach one, whatever the bulk modulus under hydrostatic pressure condition or the Young’s modulus under triaxial stress condition. Under the subsequent unloading process, the static bulk modulus is always higher than that derived during loading. However, the unloading static Young’s modulus is larger than the loading Young’s modulus only at a relatively high deviatoric stress magnitude greater than 30 MPa, while showing an opposite trend at a low-stress condition of less than 25 MPa. From the microstructural viewpoint, it is believed that the static tests accumulate the elastic, viscoelastic, and nonelastic properties within a certain stress or strain range. In contrast to the dynamic modulus, the static modulus exhibits greater sensitivity to the pressure or stress changes under hydrostatic and deviatoric stress conditions. The strong stress dependence makes it important to consider the in situ stress conditions when establishing dynamic-static modulus relations.

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Crisco, J. J., T. C. Dunn, and R. D. McGovern. "Stress Wave Velocities in Bovine Patellar Tendon." Journal of Biomechanical Engineering 120, no. 3 (June 1, 1998): 321–26. http://dx.doi.org/10.1115/1.2797997.

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The velocity of longitudinal stress waves in an elastic body is given by the square root of the ratio of its elastic modulus to its density. In tendinous and ligamentous tissue, the elastic modulus increases with strain and with strain rate. Therefore, it was postulated that stress wave velocity would also increase with increasing strain and strain rate. The purpose of this study was to determine the velocity of stress waves in tendinous tissue as a function of strain and to compare these values to those predicted using the elastic modulus derived from quasi-static testing. Five bovine patellar tendons were harvested and potted as bone–tendon–bone specimens. Quasi-static mechanical properties were determined in tension at a deformation rate of 100 mm/s. Impact loading was employed to determine wave velocity at various strain levels, achieved by preloading the tendon. Following impact, there was a measurable delay in force transmission across the specimen and this delay decreased with increasing tendon strain. The wave velocities at tendon strains of 0.0075, 0.015, and 0.0225 were determined to be 260 ± 52 m/s, 360 ± 71 m/s, and 461 ± 94 m/s, respectively. These velocities were significantly (p < 0.01) faster than those predicted using elastic moduli derived from the quasi-static tests by 52, 45, and 41 percent, respectively. This study has documented that stress wave velocity in patellar tendon increases with increasing strain and is underestimated with a modulus estimated from quasi-static testing.

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Hopulele, Ion, Mihai Axinte, and Carmen Nejneru. "Alloys with Acoustic Properties." Applied Mechanics and Materials 657 (October 2014): 417–21. http://dx.doi.org/10.4028/www.scientific.net/amm.657.417.

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Considering that, in Accordance with the Laws of Physics, the Sound Travels only through Elastic Bodies, the Main Characteristic of an Acoustic Material is the Elasticity. Classifying the Metallic Materials in this Regard is Quite Difficult, as the Elasticity is Characterized by more than One Component (static Elastic Modulus, Dynamic Elastic Modulus, Static Elastic Limit, Elastic Limit, Elastic Deformation Linearity, Damping Capacity). Best Acoustic Properties of some Metallic Materials are Widely Used in the Construction of Transducers, Musical Instruments, Bells Etc. for this Purpose, a Study on Three Metallic Materials was Conducted: a Cusn Alloy for Bells, a Cast Aluminum Alloy and a Martensitic Cast Iron. this Study Highlights both the Chemical Composition, Structure, Mechanical Properties and Damping Capacity of Sounds.

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Lee, Byung Jae, Seong-Hoon Kee, Taekeun Oh, and Yun-Yong Kim. "Evaluating the Dynamic Elastic Modulus of Concrete Using Shear-Wave Velocity Measurements." Advances in Materials Science and Engineering 2017 (2017): 1–13. http://dx.doi.org/10.1155/2017/1651753.

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The objectives of this study are to investigate the relationship between static and dynamic elastic moduli determined using shear-wave velocity measurements and to demonstrate the practical potential of the shear-wave velocity method for in situ dynamic modulus evaluation. Three hundred 150 by 300 mm concrete cylinders were prepared from three different mixtures with target compressive strengths of 30, 35, and 40 MPa. Static and dynamic tests were performed at 4, 7, 14, and 28 days to evaluate the compressive strength and the static and dynamic moduli of the cylinders. The results obtained from the shear-wave velocity measurements were compared with dynamic moduli obtained from standard test methods (P-wave velocity measurements according to ASTM C597/C597M-16 and fundamental longitudinal and transverse resonance tests according to ASTM C215-14). The shear-wave velocity measured from cylinders showed excellent repeatability with a coefficient of variation (COV) less than 1%, which is as good as that of the standard test methods. The relationship between the dynamic elastic modulus based on shear-wave velocity and the chord elastic modulus according to ASTM C469/C469M was established. Furthermore, the best-fit line for the shear-wave velocity was also demonstrated to be effective for estimating compressive strength using an empirical relationship between compressive strength and static elastic modulus.

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Asef, Mohammad Reza, and Mohsen Farrokhrouz. "A semi-empirical relation between static and dynamic elastic modulus." Journal of Petroleum Science and Engineering 157 (August 2017): 359–63. http://dx.doi.org/10.1016/j.petrol.2017.06.055.

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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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Yin, Shui Ping, and Min Yu. "Visco-Elastic Study on Filled Polymer Composites." Advanced Materials Research 239-242 (May 2011): 2038–41. http://dx.doi.org/10.4028/www.scientific.net/amr.239-242.2038.

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Dynamic mechanical behavior of materials, which is the response under cyclic stress(cyclic strain/force) in vibration condition, is different from its static behavior. The latter is the behavior of material in a monotonic increasing stress(strain/force). Dynamic mechanics analysis (DMA) is a method to measure the dynamic stiffness and damping in a lower stress level(linear elastic and lower than its yield strength). In the paper, dynamic mechanical experiments of filled polymer materials, polysulfone(PSU) and polyurethane(PUR), were performed on EPLEXOR 500N which manufacturing by GABO of Germany, the relationship of storage modulus E', loss modulus E" and loss tangent to pre-static load and frequency were systemically analyzed.

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Chang, Ching S., and Ching L. Liao. "Estimates of Elastic Modulus for Media of Randomly Packed Granules." Applied Mechanics Reviews 47, no. 1S (January 1, 1994): S197—S206. http://dx.doi.org/10.1115/1.3122814.

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The model of static hypothesis is not readily available for granular material treated as a collection of particles. Unlike other types of material, the internal stresses in a granular system are concentrated at discrete inter-particle contacts. In this paper, we propose a static hypothesis and a micromechanical description of strain considering the packing structure. The upper and lower estimates of the elastic moduli for granular materials are derived in explicit terms of the inter-particle properties.

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Wu, Feng He, Xiao Peng Xu, Jun Wang, and Jun Wei Fan. "Static Stiffness Optimization of Large Ram Based on Equivalent Elastic Modulus." Key Engineering Materials 621 (August 2014): 9–18. http://dx.doi.org/10.4028/www.scientific.net/kem.621.9.

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The finite element model of heavy-duty machine tool’s ram components has a large number of elements, many contact pairs for assembly and a large-scale optimization calculation, which make the optimization difficult to conduct. To solve this problem, a static stiffness optimization method of the large component based on the equivalent elastic modulus is put forward. The proposed method is applied to super-heavy-duty CNC floor-type milling and boring machine of TK6932 as a case study. Based on the principle of the equivalent stiffness, the ram assembly with complex constraints and contacts is equivalent to a ram part without other components, the calculation method of the equivalent elastic modulus is analyzed and the equivalent elastic modulus formula of the ram under the bending load is derived. Taking the four box-walls’ thickness and the three stiffened-plates’ thickness of the ram as the optimization variables, the minimal volume under static loading as the target and the maximal displacement and stress as the constraints, the optimized mathematical model of the ram’s equivalent static stiffness is established. The results of the optimization are rounded according to the sensitivity analysis. Besides, the optimization effect is proved by simulation through the finite element technology. The optimization procedure and results show that the simplified method based on equivalent elastic modulus presented in the paper can control the calculation scale effectively, and ensure the process of the optimization smooth.

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Pani, Luisa, and Lorena Francesconi. "Ultrasonic Test on Recycled Concrete: Relationship among Ultrasonic Waves Velocity, Compressive Strength and Elastic Modulus." Advanced Materials Research 894 (February 2014): 45–49. http://dx.doi.org/10.4028/www.scientific.net/amr.894.45.

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In this paper an experimental program has been carried out in order to compare compressive strength fcand elastic static modulus Ecof recycled concrete with ultrasonic waves velocity Vp, to establish the possibility of employing nondestructive ultrasonic tests to qualify recycled concrete. 9 mix of concrete with different substitution percentage of recycled aggregates instead of natural ones and 27 cylindrical samples have been made. At first ultrasonic tests have been carried out on cylindrical samples, later elastic static modulus Ecand compressive strength fchave been experimentally evaluated. The dynamic elastic modulus Edhas been determined in function of ultrasonic wave velocity Vp; furthermore the correlations among Ed, Ec, fce Vphave been determined. It has been demonstrated that ultrasonic tests are suitable for evaluating different deformative and resisting concrete performances even when variations are small.

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Zhang, Guo Zhi. "Study on the Probability Finite Element Format of Hyper-Static Shaft." Advanced Materials Research 557-559 (July 2012): 2181–84. http://dx.doi.org/10.4028/www.scientific.net/amr.557-559.2181.

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When hyper-static shaft was turned, its deformation mechanism was studied. Its finite element format was established when it was supported by the top. Considering the randomness of cutting force, elastic modulus, its length and its diameter, its probability finite element format was established. Moreover, its probability sample finite element model was established, and the effect of cutting force, elastic modulus, its length and its diameter to its maximum deflection was obtained. The study provides the method and theoretical basis for the analysis of the hyper-static.

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Sountaree, Rattapasakorn, and Mongkolwongrojn Mongkol. "Analysis of Two Surfaces in Line Contact under TEHL with Non-Newtonian Lubricants." Applied Mechanics and Materials 148-149 (December 2011): 736–42. http://dx.doi.org/10.4028/www.scientific.net/amm.148-149.736.

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This paper presents the static characteristics of two surfaces in line contact under TEHL with non-Newtonian lubricant. Modified Reynolds equation, elastic equation and energy equation were formulated to obtain the model. The model was simulated based on numerical method by using Newton-Raphson and multigrid multilevel techniques. The static characteristics of the two surfaces in line contact under TEHL such as film pressure, film thickness and film temperature profiles in the contact region were examined at various loads, speeds, roller radius and elastic modulus respectively. The results showed the significant effect of load, elastic modulus and surface velocity on the TEHL for machine element operated at severe conditions.

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Muguruma, Takeshi, Masahiro Iijima, Toshihiro Yuasa, Kyotaro Kawaguchi, and Itaru Mizoguchi. "Characterization of the coatings covering esthetic orthodontic archwires and their influence on the bending and frictional properties." Angle Orthodontist 87, no. 4 (July 1, 2017): 610–17. http://dx.doi.org/10.2319/022416-161.1.

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ABSTRACT Objective: To analyze the coatings covering esthetic orthodontic wires and the influence of such coatings on bending and frictional properties. Materials and Methods: Four commercially available, coated esthetic archwires were evaluated for their cross-sectional dimensions, surface roughness (Ra), nanomechanical properties (nanohardness, nanoelastic modulus), three-point bending, and static frictional force. Matched, noncoated control wires were also assessed. Results: One of the coated wires had a similar inner core dimension and elasticity compared to the noncoated control wire, and no significant differences between their static frictional forces were observed. The other coated wires had significantly smaller inner cores and lower elasticity compared to the noncoated wires, and one of them showed less static frictional force than the noncoated wire, while the other two coated wires had greater static frictional force compared to their noncoated controls. The dimension and elastic modulus of the inner cores were positively correlated (r = 0.640), as were frictional force and total cross-sectional (r = 0.761) or inner core (r = 0.709) dimension, elastic modulus (r = 0.777), nanohardness (r = 0.802), and nanoelastic modulus (r = 0.926). The external surfaces of the coated wires were rougher than those of their matched controls, and the Ra and frictional force were negatively correlated (r = −0.333). Conclusions: Orthodontic coated wires with small inner alloy cores withstand less force than expected and may be unsuitable for establishing sufficient tooth movement. The frictional force of coated wires is influenced by total cross-section diameter, inner core diameter, nanohardness, nanoelastic modulus, and elastic modulus.

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Feng, Peng, Feng Dai, Yi Liu, Nuwen Xu, and Pengxian Fan. "Effects of coupled static and dynamic strain rates on mechanical behaviors of rock-like specimens containing pre-existing fissures under uniaxial compression." Canadian Geotechnical Journal 55, no. 5 (May 2018): 640–52. http://dx.doi.org/10.1139/cgj-2017-0286.

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Rocks containing pre-existing fissures in underground engineering are likely to be subjected to static pre-stress and dynamic loads simultaneously. Understanding the deformation and failure mechanism of fissured rocks under coupled static and dynamic strain rates is beneficial for the stability assessment of rock engineering structures. This study experimentally investigates the mechanical behaviors of fissured specimens under coupled static and dynamic loads with different loading parameters. Our experiments reveal that the coupled static–dynamic strain rates significantly affect the strength, deformation, energy characteristics, and failure mode of fissured specimens. For each dynamic strain rate, the strength and elastic modulus of specimens feature an increase first as the static pre-stress increases up to half of the uniaxial compression strength, and then a decrease. However, for each static pre-stress of coupled loads, the strength and elastic modulus increase noticeably with increasing dynamic strain rate. From the perspective of energy partition, for each static pre-stress, the higher dynamic strain rate induces greater energy dissipation of the specimens during the coupled loading, and more elastic energy is released at the end of loading. Moreover, for each dynamic strain rate, the pre-stress of half uniaxial compression strength induces the highest released elastic energy.

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Kurakina, Elena, and Sergey Evtiukov. "Impact of static and dynamic loads of vehicles on pavement." E3S Web of Conferences 164 (2020): 03025. http://dx.doi.org/10.1051/e3sconf/202016403025.

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The present paper substantiates urgency of studies on early deterioration of pavement layers and on reasons entailing it. The aim was to investigate static and dynamic loads imposed on a road surface by vehicles in order to detect signs of early deterioration of pavement and understand its reasons. Certain tasks were set: to define diagnostic capacity for performing test works on road surface with the use of static and dynamic loading equipment; to carry out an elastic modulus analysis on the basis of static and dynamic loading tests performed; to assess strength properties of flexible pavement. The paper describes methods for determining strength properties of a road surface with the use of special static and dynamic loading equipment. The authors provide data on diagnostic capacity of tests of a pavement performed with the use of special testing equipment. The paper gives a list of potentials, advantages and fundamental features of the following units of equipment: apparatus for plate bearing tests, Dina-3M, UDN-NK, Dynatest apparatus. The main parameters of equipment for dynamic loading tests are provided. The results of both dynamic and static loading tests performed in Saint Petersburg and the Leningrad region are given. Deflection bowls and elastic modulus were determined. Coefficients of the dynamic elastic modulus being reduced to the static one were calculated. Strength properties of flexible pavement were assessed.

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Lamprecht, Raphael, Florian Scheible, Marion Semmler, and Alexander Sutor. "A Quasi-Static Quantitative Ultrasound Elastography Algorithm Using Optical Flow." Sensors 21, no. 9 (April 25, 2021): 3010. http://dx.doi.org/10.3390/s21093010.

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Ultrasound elastography is a constantly developing imaging technique which is capable of displaying the elastic properties of tissue. The measured characteristics could help to refine physiological tissue models, but also indicate pathological changes. Therefore, elastography data give valuable insights into tissue properties. This paper presents an algorithm that measures the spatially resolved Young’s modulus of inhomogeneous gelatin phantoms using a CINE sequence of a quasi-static compression and a load cell measuring the compressing force. An optical flow algorithm evaluates the resulting images, the stresses and strains are computed, and, conclusively, the Young’s modulus and the Poisson’s ratio are calculated. The whole algorithm and its results are evaluated by a performance descriptor, which determines the subsequent calculation and gives the user a trustability index of the modulus estimation. The algorithm shows a good match between the mechanically measured modulus and the elastography result—more precisely, the relative error of the Young’s modulus estimation with a maximum error 35%. Therefore, this study presents a new algorithm that is capable of measuring the elastic properties of gelatin specimens in a quantitative way using only the image data. Further, the computation is monitored and evaluated by a performance descriptor, which measures the trustability of the results.

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Li, Hui, Chi Dong, Hongwei Yu, Xin Zhao, Yan Li, Lele Cao, and Ming Qu. "Static and Dynamic Mechanical Properties of Organic-Rich Gas Shale." Geofluids 2021 (April 11, 2021): 1–9. http://dx.doi.org/10.1155/2021/6695975.

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Rock mechanical properties are critical for drilling, wellbore stability, and well stimulation. There are usually two laboratory methods to determine rock mechanical properties: static compression tests and acoustic velocity measurements. Rocks are heterogeneous, so there are significant differences between static elastic constants and the corresponding dynamic ones. Usually, static test results are more representative than dynamic methods but the static tests are time consuming and costly. Dynamic methods are nondestructive and less expensive, which are practical in the laboratory and field. In this paper, we compare the static and dynamic elastic properties of Eagle Ford Shale by triaxial compressive tests and ultrasonic velocity tests. Correlations between static and dynamic elastic properties are developed. Conversion from dynamic mechanical properties to static mechanical properties is established for better estimating reservoir mechanical properties. To better understand the relationship of static and dynamic mechanical properties, 30 Eagle Ford Shale samples were tested. According to the test results, the dynamic properties are considerably different from the static counterparts. For all tested samples, static Young’s modulus is lower than dynamic Young’s modulus, ranging from 55% to 90%. The difference of the static and dynamic Young’s moduli decreases with the increasing of confining pressure. The reason may be because the microcracks closed in high confining pressure. Correlations between static and dynamic Young’s modulus are developed by regression analysis, which are crucial to understand the rock mechanical properties and forecast reservoir performance when direct measurement of static mechanical properties is not available or expensive. There are no strong correlations between static and dynamic Poisson’s ratios observed for the tested samples. Two potentially major reasons for the discrepancy of the static and dynamic properties of Eagle Ford Shale are discussed. Lithology and heterogeneity may be the inherent reasons, and external causes are probably the difference in strain amplitude and frequency.

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Leitão, T., S. J. Picken, and E. Mendes. "Static and Dynamic Electro-Response of a Triblock Polymer Gel." Advances in Science and Technology 54 (September 2008): 90–95. http://dx.doi.org/10.4028/www.scientific.net/ast.54.90.

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Dielectric elastomers, a class of electroactive polymers, are specially promising due to their proven high actuation strain and energy density. Their electromechanical response is described by the Maxwell stress, where the level of strain reached depends mostly on the dielectric constant, elastic modulus and applied electric field. Since a decrease in modulus can enhance the elastomer response, swelling in appropriate solvents, transforming them into gels may enhance actuation. Tri-block copolymer gels offer a large range of possibilities since the mechanical properties and electroactive behaviour of these physically crosslinked materials can be adjusted by varying the polymer concentration, morphology and molecular weigh between crosslinks. In this work efforts were undertaken in reducing the elastic modulus by selective swelling of the elastomer midblocks with an organic oil. Strain responses to static and dynamic electrical stimuli were considered and, in particular, the effect of the frequency on the mechanical efficiency was investigated in detail. A simple theoretical model describing the frequency response was formulated.

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Misák, Petr, Tomáš Vymazal, Dalibor Kocáb, and Barbara Kucharczyková. "Repeatability and Reproducibility of the Static Elastic Modulus of Concrete Measurement." Solid State Phenomena 272 (February 2018): 214–19. http://dx.doi.org/10.4028/www.scientific.net/ssp.272.214.

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In recent years, the static modulus of elasticity is one of the most discussed property of hardened concrete. The aim of this article is to show results of 6 performed experiments focused on test results precision. The measurements were made according to the standards ISO 6784 and ISO 1920-10. More than 20 participants (laboratories) from Europe took part in these experiments. Test results were compared using the statistical methods for interlaboratory comparison. Repeatability and reproducibility, which provide more detailed information about range of expected values of elastic modulus, are the most discussed characteristics in the article.

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Nakamura, Masatoshi, Ryo Hirabayashi, Shuhei Ohya, Takafumi Aoki, Daichi Suzuki, Mitsuki Shimamoto, Takanori Kikumoto, et al. "Effect of Static Stretching with Superficial Cooling on Muscle Stiffness." Sports Medicine International Open 02, no. 05 (September 2018): E142—E147. http://dx.doi.org/10.1055/a-0684-9375.

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AbstractThis study aimed to clarify the acute effect of static stretching (SS) with superficial cooling on dorsiflexion range of motion (DF ROM) and muscle stiffness. Sixteen healthy males participated in the cooling condition and a control condition in a random order. The DF ROM and the shear elastic modulus of medial gastrocnemius (MG) in the dominant leg were measured during passive dorsiflexion. All measurements were performed prior to (PRE) and immediately after 20 min of cooling or rested for 20 min (POST), followed by 2 min SS (POST SS). In cooling condition, DF ROM at POST and POST SS were significantly higher than that at PRE and DF ROM at POST SS was significantly higher than that at POST. In addition, the shear elastic modulus at POST was significantly higher than that at PRE and the shear elastic modulus at POST SS was significantly lower than those at PRE and POST. However, there were no significant differences in the percentage changes between PRE and POST SS between the cooling and control conditions. Our results showed that effects of SS with superficial cooling on increases in ROM and decrease in muscle stiffness were no more beneficial than those of SS alone.

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Rees, J. S., P. H. Jacobsen, and J. Hickman. "The elastic modulus of dentine determined by static and dynamic methods." Clinical Materials 17, no. 1 (January 1994): 11–15. http://dx.doi.org/10.1016/0267-6605(94)90042-6.

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Martínez-Martínez, J., D. Benavente, and M. A. García-del-Cura. "Comparison of the static and dynamic elastic modulus in carbonate rocks." Bulletin of Engineering Geology and the Environment 71, no. 2 (October 22, 2011): 263–68. http://dx.doi.org/10.1007/s10064-011-0399-y.

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Chen, Chuhao, Houde Liu, Xiaojun Zhu, Dezhi Wu, and Yu Xie. "The Impact of the Electronic Skin Substrate on the Robotic Tactile Sensing." International Journal of Humanoid Robotics 16, no. 05 (October 2019): 1950026. http://dx.doi.org/10.1142/s0219843619500269.

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The tactile sensing is of significant interest for coexisting-cooperative-cognitive robots (Tri-Co robots). In order to improve the tactile sensing performance of the robot via an electronic skin (e-skin), an auxiliary elastomeric substrate is required. This paper investigates the effect of the substrate including elastic modulus, thickness and location on the static sensing at first. It is found that thick substrate with small elastic modulus can even the force distribution effectively and improve the contact area sensing. But it brought noises and crosstalk on the e-skin when the substrate has the large deformation. In occasions of dynamic tactile sensing, the impact of substrate thickness and elastic modulus was also studied and it is found that smaller elastic modulus can help e-skin sense larger and higher frequency stimulus.

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Chen, Tian-Wen, Jin Wu, and Guo-Qing Dong. "Mechanical Properties and Uniaxial Compression Stress—Strain Relation of Recycled Coarse Aggregate Concrete after Carbonation." Materials 14, no. 9 (April 26, 2021): 2215. http://dx.doi.org/10.3390/ma14092215.

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The application of recycled coarse aggregate (RCA) made from waste concrete to replace natural coarse aggregate (NCA) in concrete structures can essentially reduce the excessive consumption of natural resources and environmental pollution. Similar to normal concrete structures, recycled concrete structures would also suffer from the damage of carbonation, which leads to the deterioration of durability and the reduction of service life. This paper presents the experimental results of the cubic compressive strength, the static elastic modulus and the stress–strain relation of recycled coarse aggregate concrete (RAC) after carbonation. The results show that the cubic compressive strength and the static elastic modulus of carbonated RAC gradually increased with the carbonation depth. The uncarbonated and fully carbonated RAC show smaller static elastic modulus than natural aggregate concrete (NAC). As the carbonation depth increased, the peak stress increased, while the peak strain decreased and the descending part of the curves gradually became steeper. As the content of RCA became larger, the peak stress decreased, while the peak strain increased and the descending part of the curves gradually became steeper. An equation for stress–strain curves of RAC after carbonation was proposed, and it was in good agreement with the test results.

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Nie, Guang Lin, Yi Wang Bao, De Tian Wan, and Yuan Tian. "Measurement of the High Temperature Elastic Modulus of Alumina Ceramics by Different Testing Methods." Key Engineering Materials 768 (April 2018): 24–30. http://dx.doi.org/10.4028/www.scientific.net/kem.768.24.

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Alumina ceramics are widely used in the demanding high temperature applications in which the high temperature elastic moduli (EHT) is a key property for their reliability and safety. In this paper, the elastic modulus of alumina was determined by dynamic method (impulse excitation technique) and static tests (three-point bending test and four-point bending test). For the static tests, the relative method was applied to determine the accurate deflection measurement in the heating furnace. The measured results revealed that the modulus of alumina slowly decreased from RT to 1000 °C and rapidly decreased with the increasing temperatures from 1000 °C to 1300°C. The EHT evaluated by dynamic method were higher than that tested by static tests with the reason of that impulse excitation technique only applied small forces onto a sample such that defects activity is negligible. Also the resonant frequencies couldn’t be measured easily at high temperature, because the vibration signal emitted by the sample was weak. The static approaches combined with relative method were beyond the limit to high temperatures, and they can be also used to evaluate the ultra-high temperature modulus.

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Kee, Seong-Hoon, Jun Won Kang, Byong-Jeong Choi, Juho Kwon, and Ma Doreen Candelaria. "Evaluation of Static and Dynamic Residual Mechanical Properties of Heat-Damaged Concrete for Nuclear Reactor Auxiliary Buildings in Korea Using Elastic Wave Velocity Measurements." Materials 12, no. 17 (August 23, 2019): 2695. http://dx.doi.org/10.3390/ma12172695.

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The main objectives of this study are (1) to investigate the effects of heating and cooling on the static and dynamic residual properties of 35 MPa (5000 psi) concrete used in the design and construction of nuclear reactor auxiliary buildings in Korea; and (2) to establish the correlation between static and dynamic properties of heat-damaged concrete. For these purposes, concrete specimens (100 mm × 200 mm cylinder) were fabricated in a batch plant at a nuclear power plant (NPP) construction site in Korea. To induce thermal damages, the concrete specimens were heated to target temperatures from 100 °C to 1000 °C with intervals of 100 °C, at a heating rate of 5 °C/min and allowed to reach room temperature by natural cooling. The dynamic properties (dynamic elastic modulus and dynamic Poisson’s ratio) of concrete were evaluated using elastic wave measurements (P-wave velocity measurements according to ASTM C597/C597M-16 and fundamental longitudinal and transverse resonance tests according to ASTM C215-14) before and after the thermal damages. The static properties (compressive strength, static elastic modulus and static Poisson’s ratio) of heat-damaged concrete were measured by the uniaxial compressive testing in accordance with ASTM C39-14 and ASTM C469-14. It was demonstrated that the elastic wave velocities of heat-damaged concrete were proportional to the square root of the reduced dynamic elastic moduli. Furthermore, the relationship between static and dynamic elastic moduli of heat-damaged concrete was established in this study. The results of this study could improve the understanding of the static and dynamic residual mechanical properties of Korea NPP concrete under heating and cooling.

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Mollahassani, Amir, AmirHooman Hemmasi, Habibollah Khademi Eslam, Amir Lashgari, and Behzad Bazyar. "Dynamic and static comparison of beech wood dovetail, tongue and groove, halving, and dowel joints." BioResources 15, no. 2 (April 3, 2020): 3787–98. http://dx.doi.org/10.15376/biores.15.2.3787-3798.

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Dynamic and static elastic properties beech wood joints were assessed. Conventional joints, namely dovetail, tongue and groove, dowel, and halving joints were prepared with beech wood (Fagus orientalis Lipsky) using polyvinyl acetate and cyanoacrylate adhesives. The results of the dynamic and static modulus of elasticity of the joints in this research indicated the highest reduction trends in halving, dowel, tongue and groove, and dovetail joints, respectively. The modulus of dovetail joint elasticity, its homogeneous joint texture, and lack of an extended adhesive line, corresponded to that of the jointed samples. The average static modulus of elasticity was approximately 10.5% lower than that of the dynamic modulus of elasticity. The results of the Student’s t-test indicated a significant difference between the mean of dynamic and the mean of static modulus of elasticity, significance at 5% level and the Pearson correlation test indicated that the dynamic and static modulus of elasticity of the samples were significant at the 5% level and indicated a positive correlation. Based on the observed correlation in the dynamic and static tests’ results, using these methods, dynamic assessment of NDTs may be regarded as an appropriate alternative in standardizing destructive static testing for wood assessment and categorization.

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Kytýř, Daniel, Nela Fenclová, Petr Koudelka, Tomáš Doktor, Josef Šepitka, and Jaroslav Lukeš. "Mapping of Local Changes of Mechanical Properties in Trabecular Interconnections." Key Engineering Materials 662 (September 2015): 129–33. http://dx.doi.org/10.4028/www.scientific.net/kem.662.129.

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This paper deals with evaluation of mechanical properties of human trabeculae in the interconnection area. Local changes in the trabecular connections were evaluated using both quasi-static nanoindenation and modulus mapping technique. Connecting point of two trabeculae was revealed by precise grinding and polishing. A rectangular region in the interconnection was selected and inspected by modulus mapping procedure. Moreover several quasi-static indentation measurements using cube-corner indenter were performed along distinct lamellae. The obtained elastic properties were then compared with the values of the rod-like trabeculae. The comparison does not indicate significant differences in elastic properties between the trabecular rods and interconnections.

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Wang, Wen, Shiwei Zhang, Huamin Li, Shuang Gong, and Zhumeng Liu. "Analysis of the Dynamic Impact Mechanical Characteristics of Prestressed Saturated Fractured Coal and Rock." Advances in Civil Engineering 2019 (January 1, 2019): 1–10. http://dx.doi.org/10.1155/2019/5125923.

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The natural and water-saturated states of coal samples under static and static-dynamic loads were tested using the Split-Hopkinson pressure bar (SHPB) method and RMT-150 system, respectively. The differences in the strength reduction coefficient and elastic modulus reduction coefficient of water-saturated coal samples under static and static-dynamic loads were discussed. The experimental results for coal were compared with the corresponding characteristics of typical sandstone samples under static and static-dynamic loads. Furthermore, a fracture model of a hydrous wing branch fracture under static-dynamic loading was established based on the theory of fracture damage mechanics. The difference in dynamic strength between coal and sandstone samples for both the natural state and water-saturated state was analyzed. On this basis, the effect of water on the fracture surface of coal and the tensile strength and shear strength of the branch fracture surface were fully considered. In addition, criteria of the branch fracture surface for crack initiation and crack arrest were also established. Finally, the phenomenon of increasing elastic modulus in saturated coal samples was explained with this criterion.

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Qiu, Zhaoguo, You Ji, Fengpeng Zhang, and Guangliang Yan. "Experimental Investigation and Numerical Modeling of Elastic Modulus Variation with Stress during Hydration and Expansion Process of Static Cracking Agent." Applied Sciences 11, no. 9 (April 27, 2021): 3955. http://dx.doi.org/10.3390/app11093955.

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Based on the “axial-output method”, the time histories of radial and axial expansive pressures during the hydration process of static cracking agent (SCA) in a cylinder with various diameters were obtained by experiments. With the load input taken as the product of the normalized axial expansive pressure and the amplitude coefficient, a finite element model was established to simulate the experimental chemical expansion process of SCA. The relationships between elastic modulus, radial and axial expansive pressures were then obtained. The results indicate that the elastic modulus increases with increasing radial and axial expansive pressures, and then tends to be constant. The effect of Poisson’s ratio was discussed with the elastic modulus unchanged. It is shown that the Poisson’s ratio is inversely proportional to the amplitude coefficient, and has no effect on the ratio between the axial and radial expansive pressures. Finally, a mechanical model for the variation of elastic modulus with stress during the hydration process of static cracking agent was established in terms of the major principal stress. The model was verified by the experimental results, which can be extended for numerical simulation of SCA expansion under other compressive loading conditions, and then provide practical mechanical parameters for engineering application of SCA.

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Jin, Yuqi, Teng Yang, Shuai Ju, Haifeng Zhang, Tae-Youl Choi, and Arup Neogi. "Thermally Tunable Dynamic and Static Elastic Properties of Hydrogel Due to Volumetric Phase Transition." Polymers 12, no. 7 (June 30, 2020): 1462. http://dx.doi.org/10.3390/polym12071462.

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The temperature dependence of the mechanical properties of polyvinyl alcohol-based poly n-isopropyl acrylamide (PVA-PNIPAm) hydrogel was studied from the static and dynamic bulk modulus of the material. The effect of the temperature-induced volumetric phase transition on Young’s Modulus, Poisson’s ratio, and the density of PVA-PNIPAm was experimentally measured and compared with a non-thermo-responsive Alginate hydrogel as a reference. An increase in the temperature from 27.5 to 32 °C results in the conventional temperature-dependent de-swelling of the PVA-PNIPAm hydrogel volume of up to 70% at the lower critical solution temperature (LCST). However, with the increase in temperature, the PVA-PNIPAm hydrogel showed a drastic increase in Young’s Modulus and density of PVA-PNIPAm and a corresponding decrease in the Poisson’s ratio and the static bulk modulus around the LCST temperature. The dynamic bulk modulus of the PVA-PNIPAm hydrogel is highly frequency-dependent before the LCST and highly temperature-sensitive after the LCST. The dynamic elastic properties of the thermo-responsive PVA-PNIPAm hydrogel were compared and observed to be significantly different from the thermally insensitive Alginate hydrogel.

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Wang, Xinzhou, Linguo Zhao, Yuhe Deng, Yanjun Li, and Siqun Wang. "Effect of the penetration of isocyanates (pMDI) on the nanomechanics of wood cell wall evaluated by AFM-IR and nanoindentation (NI)." Holzforschung 72, no. 4 (March 28, 2018): 301–9. http://dx.doi.org/10.1515/hf-2017-0123.

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AbstractThe effects of the penetration of polymeric diphenyl methane diisocyanate (pMDI) on the chemical structure as well as the static and dynamic mechanical properties of wood cell walls (CWs) were investigated by atomic force microscopy with infrared radiation (AFM-IR) and nanoindentation (NI). Results indicated that the possible penetration of some pMDI molecules into the CW affected the mechanical properties of wood CW significantly. The physical and chemical interactions between pMDI and CW may strengthen the connections between the cell-wall materials and thus improved the static elastic modulus and short-term creep resistance of the CW. The elastic modulus (Er) of CWs was increased from 16.5 to 17.7 GPa; the creep ratio of the CWs decreased by 15% after the penetration of pMDI. Dynamic NI properties indicated that the effective penetration of pMDI had a positive effect on the reduced storage modulus (Er′), whereas it negatively affected the loss modulus (Er″) and the damping coefficient (tanδ) of wood CW in a large frequency scale.

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Huang, Bin, Yuting Zhang, Tian Qi, and Hongxing Han. "Static and Dynamic Properties and Temperature Sensitivity of Emulsified Asphalt Concrete." Advances in Materials Science and Engineering 2018 (June 10, 2018): 1–9. http://dx.doi.org/10.1155/2018/7067608.

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Asphalt concrete is a typical rheological material, which is hard brittle at low temperature and reflects soft plastic facture at high temperature; the temperature has a great influence on the mechanical properties of asphalt concrete. In order to eliminate the environmental pollution caused by hot asphalt construction, cationic emulsified asphalt can be used. This paper transforms the temperature control system for static and dynamic triaxial test equipment, which has achieved static and dynamic properties of emulsified asphalt concrete under different temperatures, and researched the temperature sensitivity of emulsified asphalt concrete materials including static stress-strain relationship, static strength, dynamic modulus of elasticity, damping ratio, and so on. The results suggest that (1) temperature has a great influence on the triaxial stress-strain relationship curve of the asphalt concrete. The lower the temperature, the greater the initial tangent modulus of asphalt concrete and the higher the intensity; the more obvious the softening trend, the smaller the failure strain of the specimen and the more obvious the extent of shear dilatancy. When the temperature is below 15.4°C, the temperature sensitivity of the modulus and strength is stronger significantly. (2) With the temperature rising, the asphalt concrete gradually shifts from an elastic state to a viscoelastic state, the dynamic modulus gradually reduces, and the damping ratio increases. When the temperature is above 15.4°C, the temperature sensitivity is obviously stronger for the dynamic elastic modulus and damping ratio. (3) The static and dynamic properties of asphalt concrete are very sensitive to the temperature. The test temperature should be made clear for the static and dynamic tests of asphalt concrete. The specimen temperature and the test ambient temperature must be strictly controlled.

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Xia, Bing Hua, Yuan Cai Liu, and Qing Wen Zhang. "Elastic Modulus Calculation of GRT Fiber-Rubberized Haydite Concrete." Advanced Materials Research 450-451 (January 2012): 423–27. http://dx.doi.org/10.4028/www.scientific.net/amr.450-451.423.

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Experiment with intensity level for the LC30 ceramsite concrete as the research object, changing the content of cement, GRT fiber, rubber powder by the orthogonal test to configure GRT fiber—rubberized haydite concrete samples, maintenance samples 28d in standard conditions and respectively testing their modulus of elasticity、standard compressive strength and apparent density. Through the analysis of the test data, using regression method to establish the GRT fiber—rubberized haydite concrete static compression modulus of elasticity experiential formula and use new test data to compare the value of calculation. By comparing test values and calculated values proved availability of the regression formula.

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Li, Xin Ping, Yi Dong Ma, Zhe Du, Chun Yan Gao, and Fu Li Ma. "Measuring the Elastic Modulus and Poisson's Ratio of Corncob by Electrical Method." Applied Mechanics and Materials 651-653 (September 2014): 460–64. http://dx.doi.org/10.4028/www.scientific.net/amm.651-653.460.

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The Elastic Modulus and Poisson's ratio of corncob were Measured by electrical method.The sensor was electric-resistance strain gauge.When the corncob was applied by force,the strain of corncob transformed into resistance changing of the sensor.Then,measure the resistance by SINOCERA YE253 programmable static strain gauge and transmit the resistance into the strain.It was found that the Elastic Modulus of corncob under the moisture content of 10.5% is 1.208×109 Pa and the Poisson's ratio is 0.33.

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Misák, Petr, Petr Daněk, Dalibor Kocáb, Michaela Potočková, Bronislava Moravcová, and Libor Topolář. "Assessment of the Influence of Multiple Cyclic Loading on the Static Modulus of Elasticity of Hardened Concrete." Solid State Phenomena 259 (May 2017): 21–24. http://dx.doi.org/10.4028/www.scientific.net/ssp.259.21.

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This paper deals with determining the dependence of the value of the static modulus of elasticity of concrete in compression on the number of loading cycles. The deformation of specimens during multiple cyclic loading was measured in the elastic region of the stress-strain curve for concrete. The specimens were subjected to up to 1500 loading cycles. The main goal of the experiment was to ascertain whether the multiple cyclic loading causes significant changes in the static modulus of elasticity.

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Krenev, Leonid I. "A penny-shaped crack in a functionally graded layer between two half-spaces with different elastic properties." MATEC Web of Conferences 226 (2018): 03013. http://dx.doi.org/10.1051/matecconf/201822603013.

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The axisymmetric static problem is considered on a pennyshaped mode I crack in an elastic inhomogeneous isotropic space. Young’s modulus of the elastic space material is non-symmetrical with respect to the crack. The procedure is proposed for approximate problem solution and determination of the stress intensity factor.

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Xu, Chao, and Dong Chen. "Density Functional Theory Investigations of the Mechanical Properties of Anatase: A Computer Simulation." Applied Mechanics and Materials 333-335 (July 2013): 1903–6. http://dx.doi.org/10.4028/www.scientific.net/amm.333-335.1903.

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The lattice parameters (lattice constants a, c), elastic properties (elastic constants, bulk modulus, shear modulus) and optical parameter (dielectric function) are investigated from a theoretical perspective using computer simulation in the frame of density functional theory. The calculated lattice constants and elastic moduli are in agreement with the theoretical results. We found that anatase can retain its stability in the pressure interval 020Gpa. The anisotropy of this compound is found to increase with applied pressure. Moreover, the dielectric functions are also discussed. The plasma frequency and static dielectric constant of TiO2 are 16eV and 6.1, respectively. * Corresponding author: Dong CHEN

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Lee, Byung Jae, Seong-Hoon Kee, Taekeun Oh, and Yun-Yong Kim. "Effect of Cylinder Size on the Modulus of Elasticity and Compressive Strength of Concrete from Static and Dynamic Tests." Advances in Materials Science and Engineering 2015 (2015): 1–12. http://dx.doi.org/10.1155/2015/580638.

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The primary objective of this study is to investigate the effects of cylinder size (150 by 300 mm and 100 by 200 mm) on empirical equations that relate static elastic moduli and compressive strength and static and dynamic elastic moduli of concrete. For the purposes, two sets of one hundred and twenty concrete cylinders, 150 by 300 mm and 100 by 200 mm, were prepared from three different mixtures with target compressive strengths of 30, 35, and 40 MPa. Static and dynamic tests were performed at 4, 7, 14, and 28 days to evaluate compressive strength and static and dynamic moduli of cylinders. The effects of the two different cylinder sizes were investigated through experiments in this study and database collected from the literature. For normal strength concrete (≤40 MPa), the two different cylinder sizes do not result in significant differences in test results including experimental variability, compressive strength, and static and dynamic elastic moduli. However, it was observed that the size effect became substantial in high strength concrete greater than 40 MPa. Therefore, special care is still needed to compare the static and dynamic properties of high strength concrete from the two different cylinder sizes.

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Journal articles on the topic 'Static elastic modulus'

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