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The dynamic modulus of elasticity (Ed), specified by ultrasonic pulse velocity measurements, is often used, especially for concrete built into construction, to estimate the static modulus of elasticity (Ec,s). However, the most commonly used Equations for such estimations do not take into account the influence of concrete moisture. The aim of this paper was to establish this influence for two series of structural lightweight aggregate concrete (LWAC) varying in their strength (40.2 and 54.3 MPa) and density (1690 and 1780 kg/m3). The effect of LWAC moisture content turned out to be much more pronounced in the case of dynamic modulus measurements than for static ones. The achieved results indicate that the moisture content of the concrete should be taken into consideration in modulus measurements as well as in Equations estimating Ec,s on the basis of Ed specified by the ultrasonic pulse velocity method. The static modulus of LWACs was lower on average by 11 and 24% in relation to dynamic modulus, respectively when measured in air-dried and water-saturated conditions. The influence of LWAC moisture content on the relationship between specified static and dynamic moduli was not affected by the type of tested lightweight concrete.

Ultra-high-performance-concrete (UHPC) is defined as concrete with compressive strength exceeding 150 N/mm2 (21,756 psi). UHPC can be fiber reinforced and displays increased mechanical performance and improved durability compared to high-strength concrete. This study presents the influence of curing/exposure conditions and concrete age on several mechanical and durability characteristics of UHPC, such as compressive strength and the static and dynamic modulus of elasticity, and the splitting and flexural tensile strengths. UHPC freezing-and-thawing resistance is also investigated. The results show that the specimens attained a compressive strength of approximately 150 N/mm2 (21,756 psi) and a modulus of elasticity greater than 50,000 N/mm2 (7,251,887 psi). The flexural characteristics depended on the fiber addition and the specimen?s dimensions. Overall, the flexural tensile strength displayed values between 14 and 34 N/mm2 (2030 to 4931 psi).

Concretes with the same strength can have various deformability that influences span structures deflection. In addition, a significant factor is the non-linear deformation of concrete dependence on the load. The main deformability parameter of concrete is the instantaneous modulus of elasticity. This research aims to evaluate the relation of concrete compressive and tensile elastic properties testing. The beam samples at 80 × 140 × 1400 cm with one rod Ø8 composite or Ø10 steel reinforcement were experimentally tested. It was shown that instantaneous elastic deformations under compression are much lower than tensile. Prolonged elastic deformations under compression are close to tensile. It results in compressive elasticity modulus exceeding the tensile. The relation between these moduli is proposed. The relation provides operative elasticity modulus testing by the bending tensile method. The elasticity modulus’s evaluation for the reinforced span structures could be based only on the bending testing results. A 10% elasticity modulus increase, which seems not significant, increases at 30–40% the stress of the reinforced span structures under load and 30% increases the cracking point stress.

Eucalyptus plantations are an important source of raw materials for the Thai forest products industry. Despite its economic value, only a few noncomprehensive papers have been published about the wood properties and fungal susceptibility of eucalyptus. Our study covered the most commonly used commercial eucalyptus clones with a wide variety of sizes from eastern Thailand. We assumed that the properties of the clones would differ based on the tree sizes. The objectives of this study were to determine the effects of diameter at breast height (DBH), size, and clone type on wood properties and mould susceptibility. The optimal usage of each log characteristic based on the log quality and properties could be used to determine the maximum payoff. The wood properties and log characteristics of five eucalyptus log classes with three clones were investigated. In general, the levels of means and standard deviations were as follows: the modulus of rupture (MOR) was between 39 ± 4.9 MPa and 66 ± 5.4 MPa, and the modulus of elasticity (MOE) was between 14.5 ± 9.7 GPa and 24.0 ± 2.7 GPa. In addition, the compression parallel to the grain was between 28 ± 3.2 MPa and 43 ± 2.4 MPa, and the compression perpendicular to the grain was between 13 ± 0.7 MPa and 19 ± 1.1 MPa. The shear strength parallel to the grain was between 10 ± 0.3 MPa and 14 ± 0.6 MPa. The cleavage and hardness were from 4.7 ± 1.6 N to 7.4 ± 0.9 N and from 3.6 ± 0.3 kN to 6.2 ± 0.6 kN, respectively. The toughness and nail withdrawal were from 27.3 ± 3.5 kN·mm–1 to 50.5 ± 1.0 kN·mm–1 and from 28.56 ± 4.1 N·mm–1 to 34.52 ± 2.8 N·mm–1, respectively. Eucalyptus clone K7 had lower MOR and other mechanical properties than clones K58 and K62 except MOE. When DBH increased, the mechanical and physical property values increased as well. This happened for all clones, and especially when DBH was over 200 mm. The results of this study showed that log characteristics, such as taper, slenderness, and crookedness, should be used for log grading standards and that each fast-growing eucalyptus clone could be applied to different product classes.

This paper reviews the existing literature on the tests used to determine the mechanical properties of women breast tissues (fat, glandular and tumour tissue) as well as the different values of these properties. The knowledge of the mechanical properties of breast tissue is important for cancer detection, study and planning of surgical procedures such as surgical breast reconstruction using pre-surgical methods and improving the interpretation of clinical tests. Based on the data collected from the analysed studies, some important conclusions were achieved: (1) the Young’s modulus of breast tissues is highly dependent on the tissue preload compression level, and (2) the results of these studies clearly indicate a wide variation in moduli not only among different types of tissue but also within each type of tissue. These differences were most evident in normal fat and fibroglandular tissues.

The accurate determination of rock elasticity modulus is crucial for geomechanical analysis and reliable rock engineering designs. Traditional experimental methods have limitations in estimating elasticity modulus, prompting the adoption of artificial intelligence and data-driven techniques to develop adaptive and accurate predictive models. This study utilized the Deep Random Forest Optimization (DRFO) algorithm, a hybrid approach combining deep learning and random forest algorithms, to predict rock elasticity modulus. The dataset consisted of 350 sedimentary rock samples from various regions in Iran, including sandstone, limestone, marlstone, and mudstone. The performance of the predictive models was assessed using confusion matrices, statistical errors, and the coefficient of determination (R 2 ). The results revealed the superior performance of the DRFO model, exhibiting a remarkably low Mean Absolute Error (MAE) of 0.180 GPa, outperforming other models. The Mean Squared Error (MSE) and Root Mean Squared Error (RMSE) values (0.026 and 0.161, respectively) confirmed the precision of DRFO’s predictions. DRFO demonstrated robustness and generalization capability, yielding excellent performance in both training and testing datasets. Moreover, accuracy and precision evaluation in the training dataset showed a high accuracy (0.97) and precision (0.97), indicating the reliability of DRFO in estimating rock elasticity modulus. The study underscores the significance of data-driven techniques, particularly the potential of DRFO in accurately predicting rock properties. It contributes valuable insights to the field of geotechnical engineering, aiding infrastructure design and ensuring the safety and stability of sedimentary rock-based structures. Further research can explore DRFO’s adaptability to different geological contexts and extend its application to other essential rock properties, advancing geotechnical and geological engineering practices. The integration of advanced data-driven approaches like DRFO can enhance rock mechanics understanding, facilitating sustainable engineering solutions for various geotechnical projects.

Successful development of an appropriate tree breeding strategy and wood utilization requires information on wood properties. This study was therefore conducted to assess wood density and mechanical properties of Pinus kesiya Royle ex Gordon grown in Malawi. Wood samples from six families of P. kesiya at the age of 30 years were used for the study. The estimated mean wood density, Modulus of Elasticity (MoE), Modulus of Rupture (MoR) and moisture content were 0.593 ± 0.001 g/cm3, 13.46 ± 0.07 GPa, 113.67 ± 0.57 MPa and 12.08% ± 0.03%, respectively. There were statistically significant (p < 0.001) differences in wood density and mechanical properties along the radial direction and stem height. Wood density and mechanical properties increased from pith to bark and decreased from the butt upwards. There were no significant (p > 0.05) differences in wood density and mechanical properties among the families. This is an indication that any tree among the families can be selected for tree improvement programs if density is considered as a variable. Wood density had a strong positive significant linear relationship with both MoE (r = 0.790; p < 0.001) and MoR (r = 0.793; p < 0.001). This suggests that it has the potential to simultaneously improve the wood density and mechanical properties of this species. Therefore, controlling wood density for the tree improvement program of P. kesiya in Malawi would have a positive impact on mechanical properties.

Ti-based alloys are accessible for use in the human body due to their good mechanical properties, corrosion resistance, and biocompatibilities. These main properties of alloys are important criteria for choosing biomedical implants for human bones or for other kinds of applications in general medicine. This paper presents a comparison of four new Ti-based alloys desired to satisfy various requirements for biomedical implants. The materials were prepared with recipes for two new system alloys, TiMoZrTa (TMZT) and TiMoSi (TMS), alloys with nontoxic elements. The presented research contains microstructure images, indentation tests, Vickers hardness, XRD, and corrosion resistance, showing better characteristics than most commercial products used as implants (Young’s modulus closer to the human bone).

Wood plays an essential role in civil construction due to its structural and sustainable properties. The longitudinal (E) and the transverse (G) modulus of elasticity are crucial for designing beams under bending, where combined deformations occur due to normal and shear stresses. However, the estimation of G for native Brazilian species still lacks standardized experimental procedures, with the simplified normative relation G = E/16 being commonly adopted. This study aims to estimate both E and G based on the Euler-Bernoulli and Timoshenko beam theories through three-point and four-point static bending tests. Four native Brazilian species and five ratios between the length and height of the cross-section (L/h) were analyzed. The results showed that, for L/h ratios below 18, the apparent modulus of elasticity was significantly affected by shear effects, exhibiting reductions of up to 18.47%. The E/G ratio ranged from 14.84 to 21.15, corresponding to a reduction of up to 7% and an increase of up to 32%, respectively, about the value proposed by ABNT NBR 7190-1 (2022). These results highlight the importance of considering specimen proportions and shear effects in the estimation of wood elasticity moduli obtained from bending tests.

In the distribution transformers design oval windings are used due to economic advantages. On the other hand, such windings are more susceptible to radial forces in a short circuit. A diamond dotted paper with an epoxy coating is used in order to increase the stiffness of the winding. Despite that, winding failure may occur during the short circuit, e.g. buckling of inner winding. Because of a very thin foil conductor (typically 0.5-2 mm), the most critical is inner low voltage foil winding which can collapse due to radial forces at stresses far below the elastic limit of conductor material. This paper shows an analytical approach to the calculation of critical stress in inner oval foil winding with epoxy coated insulation. Critical stress was calculated using the equation for free buckling of round winding. Equivalent Young's modulus of elasticity was obtained experimentally from the testing of the sample model loaded with bending force on a tensile test machine. A total of 12 test samples were formed from aluminium foil conductor and diamond dotted paper and cured at the temperature of 105°C. The results were successfully verified on distribution transformers subjected to short circuit withstand tests.