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The half-through arch bridge short suspender is more prone to damage due to its high linear stiffness and special force characteristics. To analyze the vehicle-induced vibration characteristics of the short suspender during service, a half-through arch bridge finite element model and a three-axis vehicle model were established to realize the coupled vibration of the suspender axle under bridge deck unevenness excitation. The suspender was simulated using LINK element and BEAM element and separated along its axial and radial directions, and its tension-bending response characteristics was studied. The study found that the short suspender’s amplitude and frequency are higher than those of the long suspender as vehicle critical duration increases. Influenced by the tensile bending effect, the vibration, cross-section equivalent force amplitude, and impact coefficient at the anchorage end are larger than those at the center, and the lower anchorage end’s cross-section peak stress is biased towards the direction of the side column. The internal force of the short suspender is consistent with the deformation trend; its internal force coincides with the deformation trend; and its axial alternating load is generated by the axial relative deformation between the arch rib and the bridge deck, while the bending alternating load originates from the rotational deformation of the short suspender.

The fracture reason of steel wire cable is complex, and the corrosion and local bending effect of anchorage end of steel wire cable under tension are one of the main factors. Taking the steel wire of an arch bridge cable as the research object, the notch method was used to simulate the corrosion pits on the surface of the steel wire, and the tension and bending mechanical properties of the high strength notched steel wire were tested. The bending finite element model of the high strength steel wire was established by ANSYS WORKBENCH, and the tension and bending mechanical properties of the notched steel wire under different vertical loads and pretension were studied. The test and calculation results show that the test data are close to the finite element calculation results and the variation law is consistent. Under the same vertical load, the deformation of steel wire notch decreases with the increase of pretension; The stress at the bottom of the notch is the largest at 180˚ direction and the smallest at 90˚ direction of the vertical load.Under the same vertical load and pretension, the stress of spherical shape at the notch is the largest, followed by ellipsoid shape, and groove shape is the smallest, and there is a high stress zone at the edge of groove shape. When the pretension is applied, the initial stress increases with the increase of pretension, while the stress at the notch caused by bending decreases with the increase of pretension.

This study deals with the calibration of Bauschinger effect on DP980 and TRIP1180 sheet metals with three cyclic material tests: tension/compression, shear/reverse shear, and bending/reverse bending. An in-plane simple shear jig, in which the grip bolts are evenly positioned surrounding a specimen to prevent the specimen from slipping, is developed for shear/reverse shear test. A new concept of electronic bending/reverse bending tester, which operates on brushless DC motor and can be speed-controlled, is designed for bending/reverse bending tests. In the newly devised bending/reverse bending test, the gaps between specimen and grip make the specimen deform like pure bending with only four points touching. The material parameters of Yoshida-Uemori (YU) model are determined from tension/compression, shear/reverse shear, and bending/reverse bending tests. The calibrated material properties for the Bauschinger effect are verified with the application for U-draw bending test. The springback prediction results based on the three loading/reverse loading tests are comparatively evaluated with various blank holding forces.

The deformation behavior of duplex stainless steel under tension and bending, accompanied by a pulsed current and when heated by an external source, is investigated. The stress–strain curves are compared at the same temperatures. The contribution to the decrease in flow stresses is greater when using a multi-pulse current at the same temperature, compared to external heating. This confirms the presence of an electroplastic effect. An increase in the strain rate by an order of magnitude reduces the contribution of the electroplastic effect from single pulses to the reduction in flow stresses by 20%. An increase in the strain rate by an order of magnitude reduces the contribution of the electroplastic effect from single pulses to the reduction in flow stresses by 20%. However, in the case of a multi-pulse current, the strain rate effect is not observed. Introducing a multi-pulse current during bending reduces the bending strength by a factor of two and the springback angle to 6.5.

Quantitative parameters for a two-state cooperative transition in duplex DNAs were finally obtained during the last 5 years. After a brief discussion of observations pertaining to the existence of the two-state equilibrium per se, the lengths, torsion, and bending elastic constants of the two states involved and the cooperativity parameter of the model are simply stated. Experimental tests of model predictions for the responses of DNA to small applied stretching, twisting, and bending stresses, and changes in temperature, ionic conditions, and sequence are described. The mechanism and significance of the large cooperativity, which enables significant DNA responses to such small perturbations, are also noted. The capacity of the model to resolve a number of long-standing and sometimes interconnected puzzles in the extant literature, including the origin of the broad pre-melting transition studied by numerous workers in the 1960s and 1970s, is demonstrated. Under certain conditions, the model predicts significant long-range attractive or repulsive interactions between hypothetical proteins with strong preferences for one or the other state that are bound to well-separated sites on the same DNA. A scenario is proposed for the activation of the ilvPG promoter on a supercoiled DNA by integration host factor.

The article presents an analysis of the results obtained during the three-point bending test for seven variants of epoxy rubber–glass composites manufactured according to innovative technology. Different contents of rubber recyclate (3, 5, and 7%) and different methods of distribution of the recyclate in the composite structure (1, 2, and 3 layers with a constant share of 5% of the recyclate) were used in the tested materials. To determine the stress values at which critical failures of the tested materials are initiated in the bending test, an analysis was carried out using the Kolmogorov–Sinai (EK-S) metric entropy calculations. The analysis results showed that for each of the above-mentioned variants of the tested epoxy–glass composites, the onset of critical changes occurring in the material structure occurs below the recorded values of the flexural strength Rmg. The decrease in the RmgK-S value in relation to Rmg is different for different material variants and depends mainly on the % content of rubber recyclate and the amount and method of decomposition of rubber recyclate in the layers of the analyzed materials. The research showed that the introduction of rubber recyclate into the composition of composites has a positive effect on their strength properties. This process allows for the efficient use of hard to degrade waste and opens up the possibility of using the newly developed materials in many industrial sectors.

This study examines the specimen size-dependent deformation behavior of commercially pure titanium grade 4 (cp-Ti grade 4) sheets under tension, with strain paths between uniaxial tension (UT) and plane-strain tension and compares the results with cyclic bending under tension (CBT) data. Specimens of varying widths (11.7, 20, 60, 100, and 140 mm) were tested in both rolling (RD) and transverse (TD) directions. The research employed digital image correlation for full-field strain measurements, finite element simulations, and fracture surface thickness data. Contrary to traditional forming concepts, i.e., the forming limit diagram (FLD) has the lowest major strain at the plane-strain condition, and the fracture forming limit has decreased major strain with increasing (less negative) minor strain, wider specimens exhibited higher major strains at strain localization and fracture under UT. In contrast, CBT findings showed decreased formability with increasing width, i.e., closer to plane-strain deformation, as expected. Strain distribution analyses revealed a transition from nearly uniform deformation in narrow specimens to multiaxial strain states in wider specimens. Thickness measurements along the fracture surface revealed a steeper profile in UT compared to CBT, indicating more localized deformation and necking in UT. In comparison with AA6016-T4, the cp-Ti grade 4 showed greater thickness, suggesting lower susceptibility to localized thinning. Strong anisotropy was observed between the RD and TD, with TD specimens showing higher formability and steeper thickness gradients in UT. Strain fields, along with thickness reduction and adiabatic heating, are used to rationalize the observed width-sensitive deformation behavior of cp-Ti sheets. Notably, CBT improved overall formability compared to UT due to its ability to distribute strain more evenly and delay critical necking. The contrasting trends between simple UT and CBT emphasize the relationship between loading conditions, specimen geometry, and material behavior in determining formability. These findings highlight the ability of the CBT test to create known and desired deformation effects, i.e., lower major strain at failure with increasing specimen width, and more uniform deformation, i.e., consistent thinning across the specimen width, for cp-Ti. Given the observed effects of width in UT, the selection of the testing method is critical for cp-Ti to ensure that results reflect expected material behavior.

A systematic experimental and theoretical investigation of the elastic and failure properties of ZnO nanowires (NWs) under different loading modes has been carried out. In situ scanning electron microscopy (SEM) tension and buckling tests on single ZnO NWs along the polar direction [0001] were conducted. Both tensile modulus (from tension) and bending modulus (from buckling) were found to increase as the NW diameter decreased from 80 to 20 nm. The bending modulus increased more rapidly than the tensile modulus, which demonstrates that the elasticity size effects in ZnO NWs are mainly due to surface stiffening. Two models based on continuum mechanics were able to fit the experimental data very well. The tension experiments showed that fracture strain and strength of ZnO NWs increased as the NW diameter decreased. The excellent resilience of ZnO NWs is advantageous for their applications in nanoscale actuation, sensing, and energy conversion.

Necking and barreling deformation behaviors occurred simultaneously during the bending test of a single-crystal gold micro-cantilever (sample A) with the loading direction parallel to the [1-10] orientation and the neutral plane parallel to the [110] orientation. In contrast, for another single-crystal gold micro-cantilever, sample B, with the loading direction aligned parallel to the [0.37 −0.92 0.05] orientation and the neutral plane parallel to the [0.54 0.28 0.78] orientation, predominant slip band deformation was noted. Sample A exhibited activation of four slip systems, whereas sample B demonstrated activity in only a single-slip system. This difference suggests that the presence of multiple slip systems contributes to the concurrent occurrence of necking and barreling deformations. Furthermore, variations in the thickness of the micro-cantilevers resulted in observable strengthening, indicating that the effect of sample size is intricately linked to the geometry of the cross-section, which we have termed the “sample geometry effect”.

The sulfur and petrochemical industries, in Iraq country, generate millions of tons of sulfur waste (SW) and waste polymers especially waste polyethylene (WPE) and waste polypropylene (WPP) which goes into landfills every year. To prevent solid waste pollution and preserve land resources, SW, WPE, and WPP will be recycled and used effectively when combined with aggregate. The study involved the construction of sulfur waste asphalt concrete (SWAC) combinations using virgin, WPE, and WPP-asphalt binders. The weight of WPE and WPP polymers was fixed at 5%, whereas the SW concentration in the asphalt concrete (AC) mixture was set at 5% (by weight of aggregate) (by weight of asphalt). The Marshall Stability, Marshall Quotient, indirect tension, tensile strength ratio, semi-circular bend, and Kim tests for deformation strength were carried out to assess the performance and durability. According to the findings of these tests, WPE and WPP-SWAC combinations at the recommended binder content exceed the minimum ASTM criteria of 8kN stability, 2–4 mm flow, 3–5% air voids, and 14% VMA. Performance and durability of SWAC mixtures are improved by WPE and WPP. Compared to the WPP–SWAC mix, the WPE–SWAC mixture demonstrated superior functionality and endurance (i.e., lower deformation phenomenon, crack propagation, and moisture damage). This study found that where they are available and transportation costs are less than for virgin materials, SW, WPE, and WPP can be recovered and used as sustainable materials for paving applications.