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Purpose: This paper investigates the biomechanical benefits of using hybrid constructs that combine cannulated screws with tension band wiring (TBW) cerclage compared to cannulated screws with anterior Variable Angle locking neutralisation plates (VA LNP). These enhancements can bear heavier loads and maintain the repaired patella's integrity, in contrast to traditional methods. Method: Eighteen fresh‐frozen human cadaver patellae were carefully fractured transversely at their midpoints using a saw. They were then divided into two groups of nine for subsequent utilisation. Fixation methods included Cannulated Screw Fixation added with either TBW or VA LNP Fixation Technique. Cyclic loading simulations (500 cycles) were conducted to mimic knee motion, tracking fracture displacement with Optotrak. After that, the constructs were secured over a servo‐hydraulic testing machine to determine the load‐to‐failure on axial mode. Results: The average fracture displacement for the anterior neutralisation plate group was 0.09 ± 0.12 mm, compared to 0.77 ± 0.54 mm for the tension band wiring with cannulated screw group after 500 cyclic loading. This result is statistically significant (p = 0.004). The anterior neutralisation plate group exhibited a mean load‐to‐failure of 1359 ± $\pm \,$21.53 N, whereas the tension band wiring group showed 780.1 ± 22.62 N, resulting in a significant difference between the groups (p = 0.007). Conclusion: This research highlights the superior biomechanical advantage of VA LNP over TBW for treating simple transverse patella fractures with two cannulated screws. It also highlights how the TBW is still a valuable option considering the load‐to‐failure limit. Level of Evidence: Not Applicable. [ABSTRACT FROM AUTHOR]

Braided composite structures, characterized by their inherent brittleness, necessitate precise damage prediction and prevention to ensure structural integrity/reliability. This study introduces an innovative method for enhancing damage resistance in tubular triaxial hybrid braided composites. These composites employ Epoxy resin as the matrix, with polyester serving as the bias yarn, and glass and basalt as the axial yarns, woven at varying braiding angles. Tensile tests reveal a compelling trend: a reduction in the braiding angle correlates with an increase in the failure load, indicative of quasi‐ductile behavior. A model is also derived for predicting tensile elastic modulus, which demonstrates a strong correlation with experimental results. Furthermore, finite element simulations are utilized to analyze damage within the triaxial hybrid braided composite specimens, providing empirical confirmation of progressive damage occurrence. This research offers a promising avenue for designing/manufacturing advanced composite materials with superior damage‐resistance holding immense potential across a spectrum of engineering applications. Highlights: The tubular triaxial hybrid braided composites were produced by Epoxy resin as the matrix, with polyester as the bias yarn, and glass and basalt as the axial yarns at different braiding angles.An innovative method was introduced for enhancing damage resistance in tubular triaxial hybrid braided composites.The effect of operating parameters (braiding angle, type of bias yarns, production method) was investigated.Was tried to predict tensile modulus values in tubular triaxial hybrid braided composites by finite element simulation and developed equations.Finite element simulation exhibited excellent performance in the prediction of tensile behavior of structures manufactured by the innovative method. [ABSTRACT FROM AUTHOR]

A better understanding of the tensile performance and tensile failure mechanism of cement paste is significant in preventing rock reinforcement failure. Therefore, this paper aims to reveal the tensile performance and failure mechanism of a modified Portland cement: Stratabinder HS cement. To achieve this objective, the split tensile test was conducted on specimens followed by simulating the failure mechanism numerically. The results indicated that the water–cement rate significantly influenced the tensile performance of the cement paste. When the water–cement rate increased from 0.35 to 0.42, the tensile strength declined from 1.9 MPa to 1.5 MPa. It was also observed that vertical tensile failure constantly occurred regardless of the water–cement rate. During the testing process, tensile cracks and shear cracks occurred. The increasing rate in the number of specimen cracks was dependent on the tensile stress state. Before the tensile stress reached the peak, the crack quantity increased slightly. After the peak, the crack quantity increased dramatically. During the vertical loading process, horizontal tensile stress occurred in the specimen. This horizontal tensile stress zone showed a diamond shape. The higher the tensile stress is, the larger the area of the horizontal tensile stress zone. When the tensile strength was reached, horizontal tensile stress mainly concentrated at the vertical centre of the specimen. This finally led to tensile failure of the specimen. This paper indicated that the water–cement rate was the key factor in evaluating the tensile strength of the Stratabinder HS cement. [ABSTRACT FROM AUTHOR]

A high degree of alteration causes swelling, disintegration and argillization of granite and thus weakens its physical and mechanical properties. Very few experimental studies, however, have been conducted to quantitatively characterize the strong-to-weak transition of the mechanical behaviours of granite affected by varying degrees of alteration. A new miniature tensile instrument system, which can visualize the failure process and simultaneously record the stress–strain curves, was utilized to test the tensile strength of dog-bone sliced samples of altered granite. Meanwhile, an improved quantitative method was proposed to characterize the alteration degree. The results demonstrate that the tensile strength of granite decreases significantly with increasing alteration rate, while the strain at the peak strength and fracture angle increase. Additionally, the orientation of weaker crystals and the mineral size distribution significantly affect fracture propagation. But the effect will be weakened as the alteration rate increases. On the basis of fracture angle, tensile peak strength, strain at peak strength, and microscopy images of crack initiation and propagation, three major classes of fractures are identified from the test results: (1) extension fracture at a low alteration rate: crack initiates and propagates along biotite-brittle mineral interfaces; (2) shear fracture at a high alteration rate: intragranular crack initiates within altered feldspar and propagates along the interior of altered mineral grains; (3) hybrid fracture at a moderate alteration rate: the above two failure phenomena coexist. A simple model that considers the fracture process of altered granite was proposed to explain the transition from extension fracture to shear fracture. Highlights: A new visual miniature tensile instrument is utilized to capture the crack initiation and propagation. An improved quantitative method is proposed to characterize the alteration degree of granite. As alteration degree increases, the tensile strength of granite significantly decreases, whereas both the strain and the fracture angle increase. The transition from extension fracture to shear fracture of altered granite is detected. [ABSTRACT FROM AUTHOR]

The mechanical behavior of loess is highly predicated on variation in its moisture content. While the impacts of the water content on the shearing behavior and collapsibility of loess have been extensively studied, its effect on tensile characteristics has received relatively little attention. In this study, a series of tensile tests were conducted on remolded specimens of a clayey loess that were collected from Ili Valley in China. Two sets of loess specimens with varying water contents were prepared separately using wetting and drying methods. The influence of the water content on the tensile stress–strain response, failure mode and tensile strength was investigated by combining the tensile test results and particle image velocimetry (PIV) analysis. On this basis, a nuclear magnetic resonance (NMR) test and scanning electron microscopy (SEM) observations were implemented in order to assist with the interpretation of the underlying mechanism. The test results indicate that the tensile failure process and the variation of tensile strength with varying water contents differ for specimens that are prepared with wetting and drying methods; a finding which arises from the differences in the soil microstructure, clay–water interaction and the distribution of capillary and adsorbed water. This research has shown that the tensile strength of clayey loess is essentially dominated by the clay's hydration/cementation and the development of capillary and adsorption suction as well as the microstructural evolution that occurs with the change in the water content. Based on the experimental observations, a conceptual model is proposed in order to interpret the effect of water content on loess' tensile behavior. [ABSTRACT FROM AUTHOR]

The paper presents a novel family of strain-based beam finite elements (FE) for analysis of tensile failure of a reinforced concrete bar (RC bar), with results of the analysis being independent of the applied FE mesh. The composite bar consists of a continuous longitudinal ductile reinforcing bar(s) surrounded by brittle concrete cover, which are considered separately in the model. Longitudinal slip at the contact between the concrete cover and reinforcing bars is allowed, while their relative displacements perpendicular to the axis of the RC bar are prevented. Cracks in concrete cover occur when tensile stress in concrete exceeds its tensile strength. Propagation of partially connected crack, that is, softening of the material at the crack, is described through constitutive law in form of nonlinear relationship between stresses in concrete at the crack and the width of the crack. Each separate crack is considered discretely as a discontinuity in geometry of the element. In the analysis of cracking of concrete, it is commonly assumed that the discrete crack can occur at the nodes of FE only. However, this assumption leads to dependence of the analysis results on the employed FE mesh. The presented family of FE enables occurrence of the crack anywhere along the FE. In order to achieve this, the discrete crack is excluded from equations of FE and additional boundary conditions are introduced at the discontinuity. This approach ensures that the location of the cracks, their number and their propagation are independent of the applied FE mesh. Advantages of the novel family of FE are thoroughly presented in a parametric study which investigates influence of number of FE as well as influence of degrees of interpolation and integration on the cracking of RC bar under tensile loading. Experimental results of tensile tests on the analysed bar are available in literature. It can be concluded that the results obtained with the minimal possible number of novel FE and sufficiently high degree of numerical integration scheme, applied for solving integrals in equations of FE, are considerably more accurate than the results of previous analyses with model of discrete crack at the nodes of FE only. [ABSTRACT FROM AUTHOR]

The umbilical is one of the most important components of a subsea production system. Processing errors and environmental load deviations may occur during the manufacturing process, and the deterministic design based on safety factors is often unable to meet the needs of engineering. In the present paper, the random distribution law of the umbilical geometry parameters is considered to analyse the reliability of the umbilical under the ultimate tensile load by combining the response surface approach of reliability analysis with the finite element analysis. [ABSTRACT FROM AUTHOR]

In recent decades, numerous geotechnical hazards, including landslides, foundation settlements, and tunnel collapses, have been linked to block-in-matrix rock (bimrock), resulting in substantial damage. The investigation and analysis of the engineering properties and mechanical behavior of both the rock and soil have become increasingly intriguing research areas. However, analyzing bimrock remains a formidable challenge due to its inherent heterogeneity. In this study, to investigate the tensile behavior of the bimrock, the numerical method that couples discontinuous deformation analysis (DDA) and smoothed particle hydrodynamics (SPH) is improved. First, a tension damage model is implemented in SPH for simulating the tensile behavior of the soil. The effectiveness of the presented model is verified through the direct tensile test model and the Brazil disc split model as an indirect tensile test. The contact algorithm of DDA-SPH is then modified by adding a tensile contact spring to introduce tensile strength at the interface between the matrix and the rock in the bimrock. Through a simple pulling numerical model, the accuracy of this modification has been verified, and the appropriate tensile contact stiffness is discussed. Furthermore, using the proposed method, the overall tensile strength of the bimrock with respect to the interface tensile strength is investigated. Finally, the proposed numerical method is applied to the simulation of geoengineering problems, demonstrating the capacity to analyze the stability and large deformation of bimrocks. • A tension damage model is added to the soil-particle based SPH method for simulating the tensile behavior of the matrix. • The contact algorithm of DDA-SPH is then modified by adding a tensile contact spring to introduce tensile strength at the interface. • The overall tensile strength of the bimrock with respect to the interface tensile strength is investigated. • The proposed method is applied to analyzing the bimrock slope and bimrock shallow tunnel. [ABSTRACT FROM AUTHOR]

Considerable research has recently been undertaken to investigate the simulation of brittle fracture mechanisms using distinct element grain boundary models. However, to date, few studies have addressed the limitations of these models when used for predictive analysis. Our research suggests that mesh geometry dependencies can impart irreducible uncertainties into the method despite apparent calibration. In addition, Voronoi meshing routines can limit the kinematic freedom, and increase the degree of interlocking and localized tensile failure; whereas, more recently introduced triangular mesh geometries can have an opposite effect, increasing kinematic freedom, and predisposing models towards shear failure mechanisms. [ABSTRACT FROM AUTHOR]

In this work, the effects of acetylation modification on the plasticization properties of citrates (triethyl citrate (TEC), acetyl triethyl citrate (ATEC), tributyl citrate (TBC) and acetyl tributyl citrate (ATBC)) were investigated by using a combination of characterization techniques and molecular dynamics (MD) simulation. The tensile test show that the acetylated ATEC and ATBC have better plasticizing efficiency compared to their non-acetylated counterparts, and consequently the tensile strength and elongation at break of ATEC/PVC (ATBC/PVC) are 13.9% (18.7%) and 8.3% (2.2%) higher than those of TEC/PVC (TBC/PVC), respectively. The MD simulation results corroborate these observations and further reveal the reason for these changes. The research mainly includes three aspects: 1. Effect mechanism of acetylation modification on the interaction between citrate and PVC; 2. The changes of microstructure, energy and motion state of PVC composites during tensile process; 3. Tensile failure mechanism of PVC composites under large tensile force. In addition, the effect of acetylation treatment on toxicity of citrate was also studied. Thus, our study contributes to better understanding of the plasticizing mechanisms of citrate and proposes an optimized citrate structure with higher performance. [Display omitted] • Focus on the influence of acetylation modification on the plasticization properties of citrate. • To study the mechanism of plasticization and tensile failure of citrate/PVC composites. • Reveal the microstructure and energy changes of PVC composites during elastic deformation and plastic deformation. [ABSTRACT FROM AUTHOR]

High brittleness is the prerequisite for the creation of a hydraulic fracture network, which is crucial for shale reservoir development. The test evaluation methods are restricted in the field by lack of continuous brittleness profiles. Mineralogical evaluation cannot incorporate the external factors like stress state. The most widely used method is mechanical evaluation method based on statistical results of Young's modulus and Poisson's ratio. This method cannot explain the brittle tensile failure mechanism of shale and contradiction between high brittleness and barriers of high strength rock. With these methods, brittle evaluation and interval selection errors will happen in the application. Starting from the mechanism of rock failure and considering the effect of rock mechanical properties on brittleness, a new method for rock brittleness evaluation has been established. Firstly, the failure surface features were analyzed and the dominant mechanisms in complex failure were identified with triaxial test and scanning electron microscopy test. Secondly, a stress model for shale reservoirs with thin sand and shale interbedded was set up based on elasticity and the factors affecting the stress distribution and failure modes have been analyzed. Eventually, based on experiments and theoretical recognition, the brittleness index for shale was proposed by integrating Young's modulus, Poisson's ratio and fracture toughness. Moreover, a method for acquiring brittleness index from well logs was developed from which brittleness profiles for shale formations in Sichuan basin were obtained. Failure features analysis demonstrates that tensile failure dominates during rock brittle failure. It was observed that compression stress on rock is only relevant to mechanical parameters and independent of space location under both internal and external stresses. Finally, comparison with the results from Rickman's method and microseismic monitoring demonstrates that the method developed in this work possesses more satisfactory results of brittleness evaluation and interval selection in field application. [ABSTRACT FROM AUTHOR]

The objective of this research work was to understand the warp and weft directional tensile properties of the two-dimensional multistitched multilayer E-glass/polyester woven composites. The warp and weft directional specific tensile strength and modulus of unstitched structure were higher than those of multistitched structures as stitching caused minor warp and weft yarn filament breakages. Contrarily, the specific tensile strains of unstitched structure were slightly lower than those of all multistitched structures. The stitching yarn type, the number of stitching directions, and the stitching density generally influenced the warp and weft directional tensile properties of multistitched E-glass/polyester woven composites. The failure of warp and weft directional multistitched woven E-glass/polyester composite structures was matrix breakages, and partial and complete yarn breakages in their surfaces. They had a local delamination in their cross-sections and the delamination did not propagate to the large areas due to multidirectional stitching. Also, the failure was confined at a narrow area and resulted in the catastrophic fiber breakages. The warp and weft directional specific damaged areas of multistitched structures, in particular four-directional stitching, were significantly lower than those of the unstitched structures. This indicated that the multistitching made the structures better damage-tolerance materials. [ABSTRACT FROM AUTHOR]

The interfacial bonding process and mechanical properties of AISI (American Iron and Steel Institute) stainless steel/Q235A carbon steel were investigated by deformation bonding, heat preservation, and tensile tests. The results reveal that the deformation temperature has a beneficial effect on the bonding rate, and that the critical temperature for the large-area bonding of stainless steel and carbon steel is approximately 700 °C. However, owing to the short contact time, only a shallow diffusion of approximately 2–3 µm can be achieved. A slight decrease in the interfacial bonding rate after heat preservation is correlated to the difference between the thermal expansion coefficients of the two materials, but the thickness of the diffusion layer shows a significant increase. It was found that the strength of the composites is mostly related to the bonding rate and the strength of the relatively soft material, which can be determined using an explicit equation. Moreover, with the increase in the interfacial bonding rate, the crack source changes from the junction of the unbonded and bonded areas of the interface to the interior of the carbon steel. The failure mode evolves from cleavage brittle fracture to ductile–brittle mixed-mode fracture, and then to ductile fracture. [ABSTRACT FROM AUTHOR]