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In order to explore the methods of recycling waste paper, reduce environment pollution, and develop a circular economy, the application of waste corrugated paper to the strengthening of polylactic acid (PLA) was studied. Plant fiber from waste corrugated paper (WCPF) was used to prepare WCPF/PLA composite via co-extrusion. The WCPF was extracted from the waste corrugated paper by beating in a Valli beating machine and grinding in a disc grinder. KH-550 coupling agent was used to modify the surface of WCPF to improve the interface adhesive strength between the WCPF and PLA matrix. The effects of the contents of WCPF and KH-550 coupling agent on the mechanical properties, microstructure, crystallization properties, and thermostability of the WCPF/PLA composite were studied. The results show that the WCPF can be well separated from each other. The WCPF can be uniformly dispersed in the PLA matrix through a co-extrusion process. WCPF can increase the mechanical strength and deformation resistance ability of WCPF/PLA composite, and KH-550 coupling agent can further improve that of the WCPF/PLA composite. This study is of obvious significance to the recycling of waste paper and the development of a circular economy. [ABSTRACT FROM AUTHOR]

Paper-type gas diffusion layer (GDL) plays the role of structural support, mass transport, electron and heat transfer in the fuel cell. The deformation and fracture behavior of paper-type GDL directly determines its physical characteristics. In this paper, we obtained the distribution function of fiber length among intersections using statistical analysis. Based on the bending theory and fracture analysis, the deformation model and the maximum allowable pressure criterion of paper-type GDL are established. The deformation modulus is related to the modulus and the initial volume fraction of carbon fiber, with an ideal value of 1.4 MPa. The tensile fracture is the main form of fiber fracture. The maximum allowable pressure is related to the expected fracture probability, the strength and the initial volume fraction of carbon fiber. The residual strain increases and the deformation modulus decreases with load range, which means that the strength of the paper-type GDL is weakened when residual strain occurs. [Display omitted] • The fiber length between intersections obeys exponential distribution function. • The compression deformation model of paper-type GDL is established. • The maximum allowable pressure criterion for the paper-type GDL is obtained. [ABSTRACT FROM AUTHOR]

A novel, biodegradable substrate based, and cost-effective flexible electrochemical sensor was developed for the highly selective and sensitive detection of one of the major neurotransmitters, dopamine, which can be utilised as a disposable electrode for point-of-care diagnostic applications. The active material CuSnB decorated over cellulose paper exhibits good sensitivities of 3.92 μA μM−1 cm−2 with a limit of detection of 0.5 nM. Moreover, the flexible sensor demonstrated superior selectivity towards co-existing metabolites such as ascorbic acid, glucose, and uric acid, in addition to stability at various mechanical deformations. [ABSTRACT FROM AUTHOR]

The research results and evaluation of the applicability of the original composition of hybrid paper based on silver nanowires (AgNWs), cellulose pulp (CP), and carbon nanotubes (CNTs) are presented and discussed. The material tested was used to manufacture sensors for mechanical deformation resulting from external influences or related to human activity interactions. The sensors were fabricated using an AgNWs + CP suspension and additives by the vacuum filtration method. The substrate obtained was machined and then laminated with a layer of poly(dimethylsiloxane) (PDMS). The recorded responses to selected types of imposed mechanical interactions in the form of changes in the relative resistance of the sensor throughout the tests showed a close cause-and-effect relationship. The response of the tested systems when applying an alternating magnetic field was also observed. The results indicate that the proposed solutions can find application in the monitoring of mechanical interactions resulting from the dynamic behavior of physical objects, as well as derived from selected human vital functions. [ABSTRACT FROM AUTHOR]

Accurately modeling the material behavior of paper and paperboard is proven to be highly demanding. Most difficulties arise from the pronounced anisotropic nature of the material. Additionally, differences in the in‐plane and out‐of‐plane behavior as well as non‐isochoric plasticity, which affects the elastic behavior, further deepen the issue at hand. Therefore, an material model is proposed, capable of capturing the anisotropic elasto‐plastic behavior of paper and paperboard. The constitutive framework was derived in a thermodynamically consistent manner, valid for finite deformations, and accounting for the coupling of in‐plane and out‐of‐plane behavior. The influence of the orthotropic anisotropy on the elasto‐plastic material response was introduced through the concept of structural tensors. A slight generalization of the elastic part of the free energy was made in order to incorporate the densification effect. A well known yield criterion was modified in order to account for some inconsistencies. Non‐isotropic hardening was considered by defining a set of coupled internal variables. The model's capabilities were demonstrated by simulating the process of folding and creasing. [ABSTRACT FROM AUTHOR]

Flexible strain sensors are indispensable components providing repeatable electronic signals responding to mechanical deformations. Nevertheless, there is a stringent demand for flexible sensors to maintain normal performance in daily use and even in harsh conditions, such as high humidity and high temperature. Herein, inspired by scorpions, a highly sensitive flexible strain sensor based on ceramic fiber paper (CFP) with superhydrophobic and high‐temperature‐resistant properties is developed by a combination of mechanical cutting and spray coating method, which minimizes performance degradation commonly seen in polymer‐based and textile‐based sensors under harsh conditions. The prepared strain sensor exhibits high sensitivity (gauge factor ≈1254), low detection limit (0.078%), fast response time (108 ms), and notable stability (over 10 000 cycles). The ultra‐high sensitivity originates from the existence of the micro‐scale cracks. To further improve stability of the device in some harsh conditions, superhydrophobic and heat‐resisting coatings consisting of SiO2 aerogels and SiO2 nanoparticles are introduced onto the surface of CFP. Owing to the synergistic effect of the high‐temperature resistance of ceramics fibers and the coatings, the device operates normally at temperature up to 220 °C with a water contact angle of 159°, showing great promises for harsh conditions, especially in the industrial and aerospace fields. [ABSTRACT FROM AUTHOR]

Cement stabilization is a widely applied technique in improving the workability and geotechnical properties of soft clay. This paper investigated the influence of cement stabilization on the soil–water characteristic curve (SWCC) and the deformation behavior of unsaturated cement–stabilized soft clay. The combined effect of cementation and partial saturation on the hydromechanical behavior of cement-stabilized soils was discussed. The SWCC of stabilized soil was measured in the full suction range under drying and wetting paths using the pressure plate method, the filter paper method, and the vapor equilibrium technique. The deformation behaviors of cement-stabilized soft soil were investigated by conducting suction-controlled oedometer tests. Furthermore, scanning electron microscope micrographs and mercury intrusion porosimetry tests were performed to investigate the effects of cement content on the evolution of soil pore structures. The test results showed that the water retention capacity of the stabilized soft clay increased with increasing cement content. The SWCC showed a significant hysteretic behavior in the boundary effect zone and transition zone, whereas the hysteretic effect was unapparent in the residual zone. The increased cement content had a more significant hysteretic effect on the SWCC. The deformation resistance capacity increased as the cement content and matric suction increased. However, the effect of matric suction on deformation resistance capacity decreased as the cement content increased. With the increase in cement content, the macropores were converted to small interaggregate pores, the pore spaces were distributed more uniformly, and the particle surface became rougher, resulting in higher water retention capacity and significant hysteresis of the SWCC. [ABSTRACT FROM AUTHOR]

Description: A multi-layer wrinkled structure of MWCNTs/polyimide aerogel-based paper was prepared using a simple method. This paper exhibits excellent responsiveness, thermal stability, and mechanical properties, and can detect the movement of mechanical devices through generated responsiveness. [Display omitted] • Multilayer wrinkled structure MWCNTs/polyimide aerogel-based paper (CPs) was prepared via a single freeze-drying-thermal extrusion-thermal imidization method. • CPs can stably generate electrical responses in high-temperature environments up to 300 °C. • CPs exhibit good tensile strength (CP-1: 117.1 MPa at 25 °C) and stability (1000 cycles). • The response generated by CPs can be utilized to monitor changes in the mechanical device. In recent years, as the electronics industry has driven the development of human civilization, flexible responsive materials have become highly favored in sensing applications. However, most flexible materials are not stable under high-temperature conditions, so only a few flexible responsive materials are suitable for high-temperature and high-strength applications. In this paper, multi-walled carbon nanotubes (MWCNTs) were added as conductive material into poly(amic acid) ammonium salt (PAAS) solutions to prepare MWCNTs/polyimide aerogel-based papers (CPs) by a simple method. The introduction of MWCNTs into the ordered multilayer folded structure of the CPs provided a conductive pathway and improved their thermal stability. When the multilayer folded structure was deformed, the MWCNTs between the layers contacted each other, increasing the number of electron transport channels and providing a larger contact area for the conductive network. When the deformation was removed, the MWCNTs in the interlayer contact zone rapidly separated, providing stable and excellent responsiveness at high temperatures (CP-2: ΔR/R 0 value of up to −0.45 at 300 °C) and favorable stability after 1000 cycles (CP-2: RV retention of 92.4 % at 25 °C and 80.5 % at 300 °C). Therefore, the prepared CPs have great application prospects in the fields of high-temperature mechanical device monitoring, sensing, and alarms. [ABSTRACT FROM AUTHOR]

The electromagnetic wave irradiation has obstructed the precise operation of the high-tech electronic equipment and threatened the health of the bodies during the 5G era. It is critical to develop electromagnetic interference (EMI) shielding materials with remarkable shielding effectiveness along with lightweight and flexible properties, while the integrations of the heat management performances have been gradually indispensable, especially in wearable electronic device applications. Anchoring the Ti 3 C 2 T x MXene nanosheets on the surfaces of the recycled carbon fibers (RCF) and assembling heterostructure can be regarded as effective strategies, while simultaneously solving the conductivity reduction and the corresponding performance degradation bottlenecks of the thermal-recycling carbon fiber. The construction of the RCF-MXene paper performs remarkable EMI shielding performance of 45.7 dB, while the specific SE/t can be improved to 7723.85 dB cm2 g-1, along with impressive photothermal and electrothermal conversion abilities. After coating PDMS layers, the flexible RCF-MXene@PDMS film maintains stable EMI shielding performance when experiencing in-situ electrothermal conversion and after 10000-cycle mechanical deformation processes. Exhibiting multifunctionality by facile synthesis strategies, the RCF-MXene-based materials provide great potential as next-generation candidates in wearable electronic devices, together with promoting the advancement of the sustainable reuse of the carbon fibers resources. [Display omitted] [ABSTRACT FROM AUTHOR]

In this work, we present a methodology to assess wrist pressure during the handwriting process. Using optical coherence tomography, it was possible to determine the deformation suffered by the paper during the handwriting process. A calibration of the deformation suffered by the paper as a function of the pressure exerted by the pen was performed, making it possible to determine several parameters of interest, such as the radius of the pen tip sphere R = 488 ± 2 ¡im, the Poisson coefficient v = 0.30 ± 0.02 and the effective Young's modulus of bond paper 75 g/m2. To this end, we developed a method for determining the Hooke modulus for a spring, with which we built a device for applying a known force to a ballpoint pen during the handwriting process. We also performed the study depending on the type of substrate, with five volunteers trying to copy the same signature on four different types of paper. Using the optical coherence tomography technique, we demonstrate that it is possible to differentiate the authorship of a signature also by the depth of deformation on the paper. The experimental procedure also made it possible to determine the Poisson's coefficient and determine the effective Young's Modulus of the paper. [ABSTRACT FROM AUTHOR]

The state-of-the-art in paper micro-mechanics calls for novel experimental data covering the full-field hygro-expansion of inter-fiber bonds, i.e., the 3D morphological changes and inter-fiber interactions. Therefore, a recently developed full-field single fiber hygro-expansion measurement methodology based on global digital height correlation is extended to orthogonal inter-fiber bonds, to investigate their full-field quasi-3D hygroscopic behavior. A sample holder has been developed which enables the quasi-3D characterization of the initial geometry of individual inter-fiber bonds, including the fiber thickness and width along the length of the fibers as well as the degree of wrap around and contact area of the bond, which are vital for understanding the inter-fiber bond hygro-mechanics. Full-field hygroscopic testing reveals the inter-fiber interactions: (i) the transverse hygro-expansion of each fiber strongly reduces when approaching the bonded area, due to the significantly lower longitudinal hygro-expansion of the other bonded fiber. (ii) The relatively large transverse strain of one fiber stretches the other crossing fiber in its longitudinal direction, thereby significantly contributing to the sheet scale hygro-expansion. (iii) Out-of-plane bending is observed in the bonded region which is driven by the significant difference in transverse and longitudinal hygro-expansion of, respectively, the top and bottom fiber constituting the bond. A bi-layer laminate model is employed to rationalize the bending deformation and an adequate match is found with the experimental data. Under the assumption of zero bending, which represents constrained inter-fiber bonds inside a paper sheet, the model can predict the contribution of the transverse strain in the bonded regions to the sheet-scale hygro-expansion. [ABSTRACT FROM AUTHOR]

[Display omitted] • Developing a superhydrophobic, kirigami, stretchable pencil-on-paper device platform. • Simultaneously detecting gas, temperature, electrophysiological signals, and providing treatments via thermal therapy and electrical stimulation. • The gas sensor exhibits a large response to NO 2 gas at elevated temperature from self-heating. • The integrated temperature sensor and electrodes accurately detect temperature and electrophysiological signals. • The thermal therapy and electrical stimulation deliver effective means to battle against inflammation/infection and treat chronic wounds. Wearable electronics with applications in healthcare, human–machine interfaces, and robotics often explore complex manufacturing procedures and are not disposable. Although the use of conductive pencil patterns on cellulose paper provides inexpensive, disposable sensors, they have limited stretchability and are easily affected by variations in the ambient environment. This work presents the combination of pencil-on-paper with the hydrophobic fumed SiO 2 (Hf-SiO 2) coating and stretchable kirigami structures from laser cutting to prepare a superhydrophobic, stretchable pencil-on-paper multifunctional sensing platform. The resulting sensor exhibits a large response to NO 2 gas at elevated temperature from self-heating, which is minimally affected by the variations in the ambient temperature and relative humidity, as well as mechanical deformations such as bending and stretching states. The integrated temperature sensor and electrodes with the sensing platform can accurately detect temperature and electrophysiological signals to alert for adverse thermal effects and cardiopulmonary diseases. The thermal therapy and electrical stimulation provided by the platform can also deliver effective means to battle against inflammation/infection and treat chronic wounds. The superhydrophobic pencil-on-paper multifunctional device platform provides a low-cost, disposable solution to disease diagnostic confirmation and early treatment for personal and population health. [ABSTRACT FROM AUTHOR]

Flexible display technology has been successfully commercialized with foldable and rollable displays. Because of the limitation of the flexible technology, stretchable displays have attracted great attention which capable of realizing freeform design as a post‐flexible display. However, no technology has yet provided sufficient stretchability and resolution to realize genuine free‐form displays. We report on a highly deformable AMOLED display which capable of elongation over 20%. Moreover, our display is capable of more than 15% shrinkage deformation. We also developed low‐temperature thermal shrink process to make the most of the potential of the display. The fabricated full‐color stretchable AMOLED shows excellent deformability with high pixel density. [ABSTRACT FROM AUTHOR]

This document is a summary of a special issue of the International Journal of Mining, Reclamation & Environment focused on innovative mine backfill materials and structures. The issue includes fourteen research papers that discuss various aspects of backfill mining, such as stability, hydration characteristics, mechanical features, and curing effects. The papers cover topics such as predicting heavy metal occurrence forms in tailings, using steel slag in backfill materials, assessing the effects of backfill ingredients on mechanical features, and developing simulation models to predict fill strength. Other papers explore the impact of curing humidity on backfill deformation and mechanical characteristics, the spatial evolution of fracture toughness under external sulphate attack, the behavior of fibre-reinforced backfill specimens under different strain rates, and the ideal Poisson's ratio for grainy backfill products. The issue also includes papers on the stress features of backfill materials at different temperatures, inclinometer state analysis for field observation, the characterization of filling effects in coal mines, mixing features of waste rocks in backfill, and the use of microgrid fibres as a reinforcement in cemented rock fills. The author expresses appreciation to the authors, referees, and editors involved in the special issue and hopes that it will contribute to the advancement of advanced fill products and methods in mining. [Extracted from the article]

How to slow down the casing deformation of shale gas wells is one of the problems to be solved urgently. Fault slip is inevitable, so how to prevent casing deformation has become an important research hotspot. In this paper, a new casing deformation control method based on solid expandable tubular (SET) technology is proposed to reduce casing deformation. This paper establishes a three-dimensional dynamic model of casing deformation considering formation pressure, frictional contact, and nonlinear loads, analyzes the advantages of using SET technology in cementing, and researches the influence of SET and annular cement parameters on casing deformation. The research results show that: on the basis of the existing cementing cement, the use of SET technology is more effective. The inner diameter of the casing after deformation will increase by more than 10 mm on the current basis, which is more conducive to subsequent construction. The expansion ratio of SET has different slowing effects on the casing deformation. In addition, the study also found that the effect of using "flexible cement + SET" is better. If only flexible cement is used, the elastic modulus of ring cement is 0.01 GPa. In order to achieve the same effect, in the case of the "flexible cement + SET" process, only annular cement with an elastic modulus of 0.1 GPa is required, which is equivalent to reducing the difficulty of cement construction. The research results of this paper provide new ideas and methods for casing deformation. [ABSTRACT FROM AUTHOR]

An advanced stability analysis of surrounding rock can assure safe construction in tunnels. However, in traditional analysis methods, geometric information on the rock mass discontinuities is obtained by a geological compass and treated as an infinitely expanded plane in a numerical simulation, which is inaccurate in both geometric and numerical models. To solve this problem, this paper studied a control network and an image stitch method to assess the accuracy of a geometric model and proposed a more accurate method to obtain the geometric information of rock mass discontinuities based on digital photogrammetry. Based on discrete fracture network and discrete element method (DFN-DEM), this paper treated the rock mass discontinuities obtained by digital photogrammetry as finite disk planes and simulated the excavation process of the Qianyu tunnel. According to the simulation results, this paper determined the specific location of the collapse disaster on the tunnel face, which is of great significance to tunnel support design. Comparing the deformation of the surrounding rock mass on the tunnel face in the simulation results with the actual situation, this paper verified the feasible accuracy of this method in analysing the stability of the surrounding rock mass on a tunnel face in advance. [ABSTRACT FROM AUTHOR]

Structural planes decrease the strength and stability of rock masses, severely affecting their mechanical properties and deformation and failure characteristics. Therefore, investigation and analysis of structural planes are crucial tasks in mining rock mechanics. The drilling camera obtains image information of deep structural planes of rock masses through high-definition camera methods, providing important data sources for the analysis of deep structural planes of rock masses. This paper addresses the problems of high workload, low efficiency, high subjectivity, and poor accuracy brought about by manual processing based on current borehole image analysis and conducts an intelligent segmentation study of borehole image structural planes based on the U2-Net network. By collecting data from 20 different borehole images in different lithological regions, a dataset consisting of 1,013 borehole images with structural plane type, lithology, and color was established. Data augmentation methods such as image flipping, color jittering, blurring, and mixup were applied to expand the dataset to 12,421 images, meeting the requirements for deep network training data. Based on the PyTorch deep learning framework, the initial U2-Net network weights were set, the learning rate was set to 0.001, the training batch was 4, and the Adam optimizer adaptively adjusted the learning rate during the training process. A dedicated network model for segmenting structural planes was obtained, and the model achieved a maximum F-measure value of 0.749 when the confidence threshold was set to 0.7, with an accuracy rate of up to 0.85 within the range of recall rate greater than 0.5. Overall, the model has high accuracy for segmenting structural planes and very low mean absolute error, indicating good segmentation accuracy and certain generalization of the network. The research method in this paper can serve as a reference for the study of intelligent identification of structural planes in borehole images. [ABSTRACT FROM AUTHOR]

Monitoring the deformation of long-span bridges is essential for assessing structural health and safety. The existing single-camera deformation measurement method is unable to meet the high-precision measurement requirement for the deformation of large-span bridges. This paper proposes a real-time deformation measurement method for the long-span bridge using multi-inertial camera system. The method is based on visual measurement which the target deformation is measured by multiple cameras. Meanwhile, inertial measurement is used to estimate the relative pose of the camera to compensate for camera motion errors. It is applied to the health monitoring system of a long-span bridge. The experimental results show that the method proposed in this paper is highly consistent with the hydrostatic leveling measurement, with a RMSE of 4.83mm. The method can accurately and real-time measure the deformation of large-span bridges with a promising engineering value. [ABSTRACT FROM AUTHOR]

Geogrid is a horizontal reinforcement material that is used in geosynthetic-reinforced pile-supported (GRPS) embankments in freeways with soft soil. Nevertheless, the long-term deformation mechanics of geogrid in the GRPS embankment under cyclic loading is not clear enough. This paper presents a laboratory model study of a GRPS embankment to study the long-term geogrid strain under cyclic loading. The effects of parameters such as number of load cycles, load frequency, geogrid layer numbers, and length of supporting piles on the long-term strain of geogrid were investigated. The results showed that geogrid strain increased with the number of load cycles, mainly developed in the first 10 000 load cycles and increased slowly in the later period. When the frequency was increased from 1 to 5 Hz, geogrid strain increased dramatically. When compared with the condition of a single geogrid layer, the upper layer of two geogrid layers caused a less geogrid strain. Compared with long piles and short piles GRPS embankments, a sufficient membrane effect of geogrid was found for long-short piles GRPS embankments. Finally, the 95% prediction interval proposed in this paper could be expressed using a logarithmic function, providing a theoretical foundation for future engineering applications. [ABSTRACT FROM AUTHOR]

Deformation effectively represents the structural integrity of concrete dams and acts as a clear indicator of their operational performance. Predicting deformation is critical for monitoring the safety of hydraulic structures. To this end, this paper proposes an artificial intelligence-based process for predicting concrete dam deformation. Initially, using the principles of feature engineering, the preprocessing of deformation safety monitoring data is conducted. Subsequently, employing a stacking model fusion method, a novel prediction process embedded with multiple artificial intelligence algorithms is developed. Moreover, three new performance indicators—a superiority evaluation indicator, an accuracy evaluation indicator, and a generalization evaluation indicator—are introduced to provide a comprehensive assessment of the model's effectiveness. Finally, an engineering example demonstrates that the ensemble artificial intelligence method proposed herein outperforms traditional statistical models and single machine learning models in both fitting and predictive accuracy, thereby providing a scientific and effective foundation for concrete dam deformation prediction and safety monitoring. [ABSTRACT FROM AUTHOR]

Time series dynamic prediction of surface deformation in mining areas can provide reference data for coal mine safety and production, which has important impacts. The combination of interferometric synthetic aperture radar (InSAR) technology and the probability integral method (PIM) is commonly used for predicting deformation. However, most surface subsidence prediction in mining areas is based on the static PIM parameters, failing to achieve the three-dimensional (3D) dynamic deformation prediction. This paper proposed a 3D deformation dynamic prediction model (InSAR-3D-CTPIM) between InSAR deformation observations and dynamic coordinate-time PIM (CTPIM) parameters, which can realize the prediction of east–west, north–south, and vertical series deformation caused by mining. The method has been validated by simulation experiments and real experiments in the mining area of Jiansheng Coal Mine in Baisha Reservoir, Henan Province, China. The results showed that the modeling accuracy was improved by 34.3% compared to the traditional multi-rate model, and the accuracy was improved by 28.5% compared to the vertical deformation obtained by the traditional static PIM method. The InSAR-3D-CTPIM model can be used to predict the evolutionary history of basin-wide surface deformation dynamics in coal mining areas, and provide a reference for the early warning and prediction of geological hazards in coal mining areas. [ABSTRACT FROM AUTHOR]

Uneven settlement phenomenon is very easy to occur in the sandy pulverized ground stratum, the underground pipe corridor longitudinal and transverse stiffness difference is obvious, so that it is easy to crack and deformation due to uneven settlement in this type of stratum. This paper carries out research on uneven settlement and cracking and deformation of Qihe tube corridor, analyzes the reasons leading to uneven settlement and the factors affecting the deformation and cracking of the tube corridor, and provides guidance for foundation treatment and tube corridor repair and mixing and reinforcement. It was found that the concrete structure of the corridor itself had exposed reinforcement, pockmarks and holes, and that cracks on the structure of the corridor sprouted and expanded from these defects. Defects and damages on the concrete structure of the pipeline corridor are contributing factors to the deformation and cracking of the members, and the uneven settlement of the foundation is the main initiating factor for the cracking and deformation. The analysis of the numerical simulation results of similar underground pipeline corridors is carried out, and it is found that the simulation results are consistent with the deformation characteristics of the Qihe pipeline corridor, which further supports the conclusions of this paper. The main stratigraphic factors contributing to the inhomogeneous settlement were found to be the water-rich and loose bodies in the lower part of the strata, as revealed by the physical means and the experimental verification boreholes. Localized hydraulic effects such as pumping further accelerate the uneven settlement of the foundation. [ABSTRACT FROM AUTHOR]

Advanced composite cementitious materials with multifunctional properties can be created by incorporating fillers and inclusions via appropriate production, characterization, and assembly processes. These composites have unique characteristics tailored for specific applications. Particularly, cementitious composites with conductive particles possess enhanced electrical and mechanical capabilities. They can assess structural integrity, being able to monitor stress, strain, and load variations, detecting incipient hazardous conditions throughout building lifespans. This improves maintenance, renovations, and structural modifications, ensuring safer and longer-lasting facilities. This paper presents experimental results of cement-based materials with carbon microfibers for structural beam elements. The samples self-diagnose internal non-uniformities, defects, fractures, and evaluate deformation variations. [ABSTRACT FROM AUTHOR]

Purpose: To investigate the changes in corrosion behaviour of severely deformed by accumulative roll bonding aluminium alloy AA1050. Design/methodology/approach: To determine the influence of the accumulative roll bonding on microstructure, texture, and grain size, electron backscattered diffraction was used. Corrosion behaviour was evaluated in a 3.5 wt.% sodium chloride water solution using anodic polarisation. Findings: It was found out that accumulative roll bonding up to eight cycles led to an increase in corrosion rate compared to annealed alloy, but the increase in the number of cycles of accumulative roll bonding from two to eight shows a tendency toward lowering corrosion rates. It has a beneficial influence on pitting corrosion susceptibility. Research limitations/implications: The presented research focuses only on the influence of texture and grain size on severely deformed aluminium alloy AA1050 corrosion. Other factors, such as accumulated during deformation stresses, could also play their role in the corrosion process. Originality/value: The paper reports results on the influence of two factors - texture and grain size, on the corrosion of severely deformed aluminium alloy AA1050. Most reports on the topic include only the influence of texture or grain size. [ABSTRACT FROM AUTHOR]

In the process of horizontal well construction, the working environment in the well is very complicated. It is difficult to determine the actual deformation and force of the coiled tubing in the wellbore from the load change at the wellhead along. In addition, the coiled tubing wrapped around the reel and entering the wellbore through the injection head may cause an initial residual bending. In this paper, the mathematical model of the coiled tubing under axial load during buckling deformation is established, and the analytical solution with the time term is derived by reasonable simplification of the model. The effect of residual bending on the post-sinusoidal buckling of the coiled tubing in the horizontal well was investigated using the separation variable method. The effect of residual bending variations on the well wall contact forces is analyzed. The research shows that the initial parameter Г is the main factor influencing the post-sinusoidal buckling of the coiled tubing with residual bending. The larger the parameter value Г, the greater the effect of the residual bending on the post-sinusoidal buckling deformation of the coiled tubing, and the earlier the critical point of the mixed sinusoidal-helical buckling of the coiled tubing appears. The compression velocity of the coiled tubing has a significant effect on the well wall contact force. The faster the compression, the greater the contact force. By introducing the time term and the separation variable, this paper provides a new method and theoretical basis for further study of the process of entering sinusoidal-helical buckling of the coiled tubing with initial residual bending. [ABSTRACT FROM AUTHOR]

This study provides a comprehensive analysis of collision and impact problems' numerical solutions, focusing on geometric, contact, and material nonlinearities, all essential in solving large deformation problems during a collision. The initial discussion revolves around the stress and strain of large deformation during a collision, followed by explanations of the fundamental finite element solution method for addressing such issues. The hourglass mode's control methods, such as single-point reduced integration and contact-collision algorithms are detailed and implemented within the finite element framework. The paper further investigates the dynamic response and failure modes of Reinforced Concrete (RC) members under asymmetrical impact using a 3D discrete model in ABAQUS that treats steel bars and concrete connections as bond slips. The model's validity was confirmed through comparisons with the node-sharing algorithm and system energy relations. Experimental parameters were varied, including the rigid hammer's mass and initial velocity, concrete strength, and longitudinal and stirrup reinforcement ratios. Findings indicated that increased hammer mass and velocity escalated RC member damage, while increased reinforcement ratios improved impact resistance. Contrarily, increased concrete strength did not significantly reduce lateral displacement when considering strain rate effects. The study also explores material nonlinearity, examining different materials' responses to collision-induced forces and stresses, demonstrated through an elastic rod impact case study. The paper proposes a damage criterion based on the residual axial load-bearing capacity for assessing damage under the asymmetrical impact, showing a correlation between damage degree hammer mass and initial velocity. The results, validated through comparison with theoretical and analytical solutions, verify the ABAQUS program's accuracy and reliability in analyzing impact problems, offering valuable insights into collision and impact problems' nonlinearities and practical strategies for enhancing RC structures' resilience under dynamic stress. [ABSTRACT FROM AUTHOR]

Persistent Scatterer InSAR (PS-InSAR) technology enables the monitoring of displacement in millimeters. However, without the use of external parameter correction, radar scatterers exhibit poor geopositioning precision in meters, limiting the correlation between observed deformation and the actual structure. The integration of PS-InSAR datasets and building databases is often overlooked in deformation research. This paper presents a novel strategy for matching between PS points and building contours based on spatial distribution characteristics. A convex hull is employed to simplify the building outline. Considering the influence of building height and incident angle on geometric distortion, an adaptive buffer zone is established. The PS points on a building are further identified through the nearest neighbor method. In this study, both ascending and descending TerraSAR-X orbit datasets acquired between 2016 and 2019 were utilized for PS-InSAR monitoring. The efficacy of the proposed method was evaluated by comparing the PS-InSAR results obtained from different orbits. Through a process of comparison and verification, it was demonstrated that the matching effect between PS points and building contours was significantly enhanced, resulting in an increase of 29.2% in the number of matching PS points. The results indicate that this novel strategy can be employed to associate PS points with building outlines without the need for complex calculations, thereby providing a robust foundation for subsequent building risk assessment. [ABSTRACT FROM AUTHOR]

In this work we propose proof-of-concept methods to detect malfunctions of the braking system in passenger vehicles. In particular, we investigate the problem of detecting deformations of the brake disc based on data recorded by acceleration sensors mounted on the suspension of the vehicle. Our core hypothesis is that these signals contain vibrations caused by brake disc deformation. Since faults of this kind are typically monitored by the driver of the vehicle, the development of automatic fault-detection systems becomes more important with the rise of autonomous driving. In addition, the new brake boosters separate the brake pedal from the hydraulic system which results in less significant effects on the brake pedal force. Our paper offers two important contributions. Firstly, we provide a detailed description of our novel measurement scheme, the type and placement of the used sensors, signal acquisition and data characteristics. Then, in the second part of our paper we detail mathematically justified signal representations and different algorithms to distinguish between deformed and normal brake discs. For the proper understanding of the phenomenon, different brake discs were used with measured runout values. Since, in addition to brake disc deformation, the vibrations recorded by our accelerometers are nonlinearly dependent on a number of factors (such as the velocity, suspension, tire pressure, etc.), data-driven models are considered. Through experiments, we show that the proposed methods can be used to recognize faults in the braking system caused by brake disc deformation. [ABSTRACT FROM AUTHOR]

Layered rock slope exists widely. Because of its special slope structure, it is prone to bending deformation and toppling failure, which is a serious threat to engineering construction and safety operation. At present, the research of layered rock slope still has great innovation potential. During the construction of Wudongde Hydropower Station on Jinsha River, safety and stability problems such as slope geological structure development, face rock unloading and relaxation, and even slip and large deformation were encountered. Through field exploration, it is found that the rock and soil stratification of the slope on both sides of Wudongde Hydropower Station is highly obvious. At present, there is a lack of research on-site long-term displacement monitoring of layered rock high-steep slope, especially for layered slope in complex hydrogeology and construction environment. In order to strengthen the research on the deformation and stability of layered rock slope, this paper analyzes the measured displacement data of Wudongde hydropower station slope, and establishes three-dimensional geological finite element model with the help of numerical simulation software. The stability of the slope is calculated by combining the finite difference method and the strength reduction method. Finally, the evolution mechanism of the deformation of the layered rock slope is explained according to the geological structure characteristics. The main conclusions of this paper are as follows: the layered slope in the dam reservoir area is prone to deformation under the combined action of long-term construction disturbance and fissure water seepage, and the construction disturbance has a strong influence on the artificial excavation area below 1070 m, and the maximum rock mass deformation and surface displacement in the artificial excavation area of the slope reach 92.2 mm and 312.5 mm, respectively. However, the influence of construction disturbance on the natural mountain above 1070 m is limited, the valley deformation of the natural mountain on the left bank of the reservoir area is higher than that on the right bank, and the cumulative deformation is still less than 20 mm. The influence of seepage on the displacement of the area with higher elevation at the top of the slope is more obvious, and the influence of excavation and other disturbances on the displacement of the artificial excavation area with lower elevation is more obvious. The deformation of the river valley in the water cushion pond behind the dam increases slowly, and the change trend of the field deformation data is mostly consistent with that of the numerical calculation. The horizontal shrinkage of the mountains on both sides shows a contraction trend on the whole, and the maximum horizontal shrinkage calculated by numerical simulation is close to 20 mm, which is located at the elevation of 990 m. [ABSTRACT FROM AUTHOR]

The propulsion system for an aircraft is one of its most crucial systems; therefore, its reliable work must be ensured during all operational conditions and regimes. Modern materials, techniques and methods are used to ensure this goal; however, there is still room for improvement of this complex system. The proposed manuscript describes a progressive approach for the mechanical properties prediction of the turbine section during jet engine operation using an artificial neural network, and it illustrates its application on a small experimental jet engine. The mechanical properties are predicted based on the measured temperature, pressure and rpm during the jet engine operation, and targets for the artificial neural network are finite element analyses results. The artificial neural network (ANN) is trained using training data from the experimental measurements (temperatures, pressure and rpm) and the results from finite element analyses of the small experimental engine turbine section proposed in the paper. The predicted mechanical stress by ANN achieved high accuracy in comparison to the finite element analyses results, with an error of 1.38% for predicted mechanical stress and correlation coefficients higher than 0.99. Mechanical stress and deformation prediction of the turbine section is a time-consuming process when the finite element method is employed; however, the method with artificial neural network application presented in this paper decreased the solving time significantly. Mechanical structural analyses performed in ANSYS software using finite element modeling take around 30–40 min for one load step. In contrast, the artificial neural network presented in this paper predicts the stress and deformation for one load step in less than 0.00000044 s. [ABSTRACT FROM AUTHOR]

The paper deals with the sleeper substructure design for a speed of 200 kph according to the Czech SŽ S4 standard. The paper includes the design of sub-ballast and capping layers. The second part of the paper is focused on transition area design. The conclusion brings recommendations of alterations which would be appropriate to incorporate into the standard. [ABSTRACT FROM AUTHOR]

The deformation behavior of deep excavations is affected by many factors, among which the geological conditions are greatly affected. Hangzhou Bay is affected by marine siltation and river alluvium, and the geological conditions within the urban area of Hangzhou are quite different. In this paper, the geological and deformation data of 79 deep excavation cases in the Hangzhou urban area were collected, and the statistical analysis showed that the deformation control of excavations in the silt area was poor. The average maximum lateral wall displacement of deep excavations of the Hangzhou urban area was 0.41%H (H was the depth of the excavation), the average value of the alluvial area was 0.22%H, and the average value of the silted area was 0.55%H. The influence of geological conditions, wall type, and construction period on the deformation of excavations was compared, and the deformation behavior of excavations in the silted area was clearly affected by various factors. [ABSTRACT FROM AUTHOR]

In this paper, a Zr–5W alloy was fabricated via casting. In order to obtain the mechanical properties of the material, quasi-static compression tests at room temperature and split Hopkinson pressure bar tests at various temperatures were carried out. The x-ray diffraction result showed that the main components of the alloy were αZr and W2Zr, where αZr is the matrix and W2Zr is the reinforcement. The metallographic characterization results showed that there were two main forms of W2Zr in the material, namely, large particle boundary and small diffuse submicrometer precipitates. The reinforcements of both distributions have the effect of increasing the strength of the material, but the small submicrometer W2Zr precipitates would cause microcrack nucleation during the late plastic deformation stage, resulting in damage softening. In order to make theoretical calculations of the mechanical properties of materials, the Johnson–Cook (JC) constitutive model and Zerilli–Armstrong (ZAM) constitutive model of the material were obtained. It was found that the JC constitutive model had poor consistency in describing material properties. Although the consistency of the ZAM constitutive model was higher than that of the JC constitutive model, it still had obvious shortcomings. Combined with the deformation mechanism of the alloy, a modified constitutive relation was established by adding damage softening terms based on the hexagonal close-packed metal constitutive model inferred by the kinetics of heat-activated dislocations. The relative error results of all working conditions show that the correlation consistency of the improved constitutive model in this paper is significantly better than that of JC constitutive and ZAM constitutive. [ABSTRACT FROM AUTHOR]

An excavator is an off-road vehicle or machine used for several types of construction activities. It has an attachment called a backhoe that is widely used for digging. While digging the earth's massive force works on bucket tips and may bring deformation in it. In this paper an attempt is made to quantify the value of the variables obtained while the all-attached backhoe is considered as a multibody, given in rotation to each joint and simulated in Ansys. The results obtained show that the deformation obtained is small at low rotation and large at high rotation rate. Comparison of the deformation, joint forces and velocity at each set of rotation has been tabulated in x, y and Z directions as well as the overall velocity, total joint force and deformation has also been calculated. This paper provides the base to study and design a multibody system which may undergo deformation so that the end effect may be obtained precisely as required in precision tools and machinery. [ABSTRACT FROM AUTHOR]

The step hollow shaft components are composed of two layers of different materials, they are formed using tube hydroforming process due to its high strength and rigidity, low weight and flexible profiles, compared to traditional casting, welding, and forming methods. These products are effectively used in industries such as the automotive, shipbuilding, aerospace and defense, and oil and gas sectors. The success of various double layer pipe hydroforming process depends on several factors, with the most important being the internal pressure path and axial loading path. This paper presents research on the effect of input loading paths on the hydroforming ability of a different two-layer metal structure - an outer layer of SUS304 stainless steel and an inner layer of CDA110 copper - using 3D numerical simulations on Abaqus/CAE software. Output criteria were used to evaluate the forming ability of the formed components, including Von Mises stress, Plastic strain component (PEmax), wall thinning, and pipe profile, based on which the input loading paths were combined during the forming process. These output criteria allow for more accurate predictions of material behavior during the hydroforming process, as well as deformation and stress distribution. This can support the design process, improve product quality, reduce errors, and increase production efficiency. The research results can be applied as a basis for optimizing load paths for the next experimental step in the near future, for undergraduate and graduate training, as well as allowing designers and engineers to optimize the process of hydroforming of different 2-layer tubes, reducing costs, improving accuracy, flexible design, minimizing risks, and increasing efficiency. [ABSTRACT FROM AUTHOR]

This paper presents the basic tools used to describe the global symmetry of so‐called bilayer structures obtained when two differently oriented crystalline monoatomic layers of the same structure are superimposed and displaced with respect to each other. The 2D nature of the layers leads to the use of complex numbers that allows for simple explicit analytical expressions of the symmetry properties involved in standard bicrystallography [Gratias & Portier (1982). J. Phys. Colloq.43, C6‐15–C6‐24; Pond & Vlachavas (1983). Proc. R. Soc. Lond. Ser. A, 386, 95–143]. The focus here is on the twist rotations such that the superimposition of the two layers generates a coincidence lattice. The set of such coincidence rotations plotted as a function of the lengths of their coincidence lattice unit‐cell nodes exhibits remarkable arithmetic properties. The second part of the paper is devoted to determination of the space groups of the bilayers as a function of the rigid‐body translation associated with the coincidence rotation. These general results are exemplified with a detailed study of graphene bilayers, showing that the possible symmetries of graphene bilayers with a coincidence lattice, whatever the rotation and the rigid‐body translation, are distributed in only six distinct types of space groups. The appendix discusses some generalized cases of heterophase bilayers with coincidence lattices due to specific lattice constant ratios, and mechanical deformation by elongation and shear of a layer on top of an undeformed one. [ABSTRACT FROM AUTHOR]

For coated paperboard with large deformations, there is limited knowledge on the mechanisms that lead to coating damage and on the key properties that affect damage. Large deformations produce complex non-linear mechanical responses which often result in significant internal damage. The objective of this work was to establish methods to directly measure local deformation at a fold using a stereo digital image correlation (DIC) technique and a folding device designed in-house. This allowed monitoring of deformation from both cross-section and surface views, from which curvature and strain could be analyzed. This approach allowed observation and quantification of the initiation and propagation of damage. Testing showed that elastic estimation of deformation is valid only at very small curvatures but is still qualitatively useful. It was found that CD fold line shows a lower strain than MD fold line at a given curvature, but it ultimately reaches a higher level of surface strain. Additionally, localized maximum surface strain was shown to correlate better with surface damage at fold than the average surface strain. Furthermore, the introduced discontinuity index can provide a useful tool to compare surface damage at fold even for paperboard samples with different thicknesses. [ABSTRACT FROM AUTHOR]

The fracture network generated by hydraulic fracturing in unconventional shale reservoirs contains numerous microfractures that are connected to macroscopic fractures. These microfractures serve as crucial pathways for shale gas to flow out from micro- and nano-scale pores, playing a critical role in enhancing shale gas recovery. Currently, more attention is being given by academia and industry to the evolution of macroscopic fracture networks, while the understanding of the microfracture mechanisms and evolution is relatively limited. A significant number of microfractures are generated during the hydraulic fracturing process of shale. These microfractures subsequently propagate, merge, and interconnect to form macroscopic fractures. Therefore, studying the fracture process of rock masses from a microscale perspective holds important theoretical significance and engineering value. Based on the authors' research experience and literature review, this paper provides a brief overview of current progress in shale microfracture research from five aspects: in situ observation experiments of microfractures in shale, formation and evolution processes of discontinuous microfractures, the impact of inhomogeneity on microfracture propagation, measurement methods for microscale mechanical parameters and deformation quantities in shale, and numerical simulation of shale microfractures. This paper also summarizes the main challenges and future research prospects in shale microfracture studies, including: (1) quantitative characterization of in situ observation experimental data on shale microfractures; (2) formation and evolution laws of macroscopic, mesoscopic, and microscopic multi-scale discontinuous fractures; (3) more in-depth and microscale characterization of shale heterogeneity and its deformation and fracture mechanisms; (4) acquisition of shale micro-mechanical parameters; (5) refinement and accuracy improvement of the numerical simulation of microfractures in shale. Addressing these research questions will not only contribute to the further development of microfracture theory in rocks but also provide insights for hydraulic fracturing in shale gas extraction. [ABSTRACT FROM AUTHOR]

The side pile is a crucial mechanical component in station construction using the PBA (pile-beam-arch) method, and its stability during the construction process cannot be overstated. The mechanical differences between single-row and double-row side piles in this construction method have garnered significant attention, yet few studies have been conducted on this matter. Therefore, this paper employs numerical simulation to compare the deformation and mechanical properties of single-row and double-row side piles (the adopted pile type is micro steel pipe pile, abbreviated as MSPP) in a metro station using the PBA method. The findings are validated through the model experiment. It is found that the soil arch effect created by the front-row pile of the double-row piles serves as the primary lining, offering a certain shielding effect to the soil stress behind the back-row pile. Notably, the soil stress values in double-row pile conditions are slightly higher compared to single-row pile condition, leading to a noticeably smaller final deformation of the pile top. The combined bending moments and axial forces of the front-row and back-row piles in double-row piles exceed those of a single-row pile. Specifically, bending moments are highest in single-row piles, followed by front-row piles and then back-row piles, while axial forces are highest in single-row piles, followed by back-row piles and then front-row piles. This suggests that the bending moments and axial forces of double-row piles are smaller than those of a single-row pile. The internal force distribution within the double-row pile is more balanced, thereby enhancing the lining strength and improving the station's safety through the PBA method. The findings in this paper can serve as valuable references for the design and construction of similar projects. [ABSTRACT FROM AUTHOR]

In the numerical simulation of earth-rock dam, accurate and reliable mechanical parameters of the dam material are the important basis for dam deformation predictions and dam safety evaluations. Based on the deformation monitoring data of Luding core wall rockfill dam, the rheological parameters of rockfill and core wall materials are inverted in this paper. Combined with the actual filling and impoundment process of the dam, the numerical simulation is carried out, and the stress deformation and differential settlement of the dam after completion and impoundment are analyzed. The results showed that the stress deformation results of the dam based on the inversion parameters were in good agreement with the actual deformation. The horizontal displacement, settlement, and principal stress of the dam during the completion period were symmetrically distributed along the core wall. The maximum horizontal displacement occurred at the main dam on both sides of the core wall and the upstream and downstream dam slopes, and the maximum settlement occurred in the middle of the core wall. During the impoundment period, under the action of reservoir water pressure and upstream rockfill wetting deformation, the deformation and stress of the dam body no longer met the symmetrical distribution law, and the maximum horizontal displacement of the dam body during the impoundment period was located at 2/3 of the upstream dam slope. The maximum settlement of the dam body was located at 1/2 of the dam height. The maximum principal stress on the upstream side of the core wall was located on the left side of the bottom of the core wall, and the minimum principal stress was also located on the left side of the bottom of the core wall. The simulation results of the deformation and stress met the general law of earth-rock dam engineering. During the completion period, the deformation inclination of the dam crest was less than 1%. During the impoundment period, the deformation inclination of the dam crest area increased due to the wetting deformation of the upstream rockfill material. At the same time, the deformation inclination of the dam crest axis was larger than that of the upstream and downstream sides, and the deformation inclination of the dam crest at the middle of the valley was the largest, but it did not exceed 3%, that is, there would be no longitudinal cracks, which is consistent with the actual situation. The research results can better predict the stress deformation and crack of the dam body, and provide important support for dam safety evaluations. [ABSTRACT FROM AUTHOR]

Inclusions are important phases affecting material properties in complicated ways. In this paper, a quantitative study of the addition of HfO2 inclusions to DZ125 nickel-based superalloys was performed. Experimental results showed that the introduction of HfO2 inclusions caused a loss of strength and ductility. The carbide morphology also changed significantly from skeletal-shaped to block-shaped, resulting in a remarkable discrepancy in the fracture behavior under quasi-in-situ tensile testing. The SEM dynamic observations showed that cracks were initiated from the skeletal carbides and almost failed to propagate into the matrix. In contrast, the damage behavior of block-shaped carbides also involved internal cracking but with a tendency to form interconnected microcracks during propagation. A crystal plasticity finite element model (CPFEM) method was further developed to study the stress/strain behavior during the deformation process, considering the crystal orientations and microstructure morphologies from the EBSD data. Those elastoplastic parameters were determined through nanoindentation experiments. Simulation results verified that blocky carbides produced a pronounced strain concentration at the interface of the carbides and matrix, thereby increasing the tendency of crack formation. This paper provides a fundamental understanding of the role of inclusions in material recycling applications. [ABSTRACT FROM AUTHOR]

Chirality and porosity are characteristic properties of nanostructured materials. Their effects on the mechanical behaviour of structural elements, such as shells, plates and beams, cannot be disregarded. In this paper, we study the thermoelastic deformation of a chiral porous circular beam loaded with an axial force and torque. The beam is also under the action of a constant temperature field. The analytical solution is obtained using the results established in a paper recently published by the Author within the context of the strain gradient theory proposed by Papanicopolous. In the constitutive equations, the chirality is introduced by a material constant parameter and the porosity is described by means of a scalar function. Displacements, microdilatation function, and stress and strain fields are expressed in explicit form and in terms of engineering constants. Explicit formulas of the stiffness of chiral porous circular beams are presented and the effects of right and left chirality are discussed. [ABSTRACT FROM AUTHOR]

The No.4 tailings pond of the Dexing Copper Mine is the second largest in Asia. The tailing pond is a dangerous source of man-made debris flow with high potential energy. In view of the lack of effective and low-cost global safety monitoring means in this region, in this paper, the time-series InSAR technology is innovatively introduced to monitor the deformation of tailings dam and significant key findings are obtained. First, the surface deformation information of the tailings pond and its surrounding areas was extracted by using SBAS-InSAR technology and Sentinel-1A data. Second, the cause of deformation is explored by analyzing the deformation rate, deformation accumulation, and three typical deformation rate profiles of the representative observation points on the dam body. Finally, the power function model is used to predict the typical deformation observation points. The results of this paper indicated that: (1) the surface deformation of the tailings dam can be categorized into two directions: the upper portion of the dam moving away from the satellite along the Line of Sight (LOS) at a rate of −40 mm/yr, whereas the bottom portion approaching the satellite along the LOS at a rate of 8 mm/yr; (2) the deformation of the dam body is mainly affected by the inventory deposits and the construction materials of the dam body; (3) according to the current trend, deformation of two typical observation points in the LOS direction will reach the cumulative deformation of 80 mm and −360 mm respectively. The research results can provide data support for safety management of No.4 tailings dam in the Dexing Copper Mine, and provide a method reference for monitoring other similar tailings dams. [ABSTRACT FROM AUTHOR]

This article considers the deformation behavior of Panda optical fiber using different models of material behavior for the tasks of predicting residual stresses after drawing when cooling from 2000 °C to room temperature (23 °C) and indenting the fiber into an aluminum half-space at different parameters. These studies were conducted for single- and double-layer protective coatings (PCs), at different values of external load and thickness of single-layer PC. This paper determined the fields of residual stresses in the fiber formed during the drawing process. They are taken into account in modeling the fiber performance in the further process of this research. This article investigated two variants of PC behavior. The influence of behavior models and the number of covering layers on the deformation of the "fiber-half-space" system was analyzed. This paper establishes qualitative and quantitative regularities of the influence of the external load magnitude and relaxation properties of PCs on the deformation and optical characteristics of Panda optical fiber. [ABSTRACT FROM AUTHOR]

This paper first proposes a novel framework for combining deep learning approach and Synthetic Aperture Radar (SAR) technique to evaluate and predict the condition of bridge displacement. The Long short-term memory (LSTM) neural network and the Small Baseline Subsets InSAR (SBAS-InSAR) are used to predict the longitudinal deformation of the bridge. Firstly, the proposed framework based on LSTM is established to obtain the relationship between the longitudinal deformation of the bridge and the influence parameters (such as temperature, temporal baseline, and others). In particular, the residual connection (RC) module is adapted to form the residual long short-term memory (Res-LSTM) neural network to improve prediction accuracy and robustness. A case study in Nanjing is analyzed to verify the performance of the proposed framework. The extracted datasets obtained from Sentienl-1 are divided into the training, validation, and testing dataset, which can satisfy the requirements in the engineering field. The R 2 and MSE of the testing datasets utilizing the proposed model are 93.17% and 15.62. Furthermore, the results indicated that the proposed framework based on Res-LSTM could predict and warn the abnormal structural deformation, extend the lifespan of structures, and minimize structural damage due to excessive deformation. [ABSTRACT FROM AUTHOR]

To develop lightweight and biomimetic structural materials, in this paper, the compressive deformation and mechanical properties of the grid beetle elytron plate (GBEP) with the same core volume as the end-trabecular beetle elytron plate (EBEP) under compression were investigated for the first time. (1) The B-type deformation mode of trabeculae is clarified, which is a higher stage of independent deformation than the Φ-type deformation mode in the beetle elytron plate (BEP). Additionally, the four deformation modes of the BEP are divided into three stages in succession from easy to difficult: C-type, Φ-type and S (B)-type deformation. This paper verifies that the compressive strength and energy absorption capacity of the GBEP increase by 35% and 87%, respectively, relative to those of the grid plate (GP) with the same volume. (2) Although the number of trabeculae of the GBEP is significantly less than that of the EBEP, each trabecula in the GBEP has one more honeycomb wall constraint than each trabecula in the EBEP. The increase range of the compressive properties of the GBEP relative to the GP is greater than that of the EBEP relative to the honeycomb plate (HP). This confirms the prediction that the compressive properties can be effectively improved by appropriately increasing the constraints on the trabeculae. This paper deepens and enriches the knowledge regarding the biomimetic application system of BEPs, lays the foundation for GBEPs, whose preparation is convenient, and accelerates the applications of GBEPs. [ABSTRACT FROM AUTHOR]

A better physical understanding of mesoscale and microscale mechanisms behind deformation and failure of paperboard material is important to optimize industrial packaging converting processes and decrease waste. In this study, these mechanisms were investigated using synchrotron X‐ray tomography during in situ continuous uniaxial tensile loading. High spatial and temporal data resolution enabled quantification of rapid changes in the material occurring before, during and after material failure. The evolution of 3D strain fields, fibre orientations and sample thickness showed that deformation and failure mechanisms differ significantly between samples tested in machine direction (MD), cross direction (CD) and 45° from the loading direction. In 45° and CD, gradual failure processes could be followed across several load steps. Immediately after failure, the in‐plane fracture region was significantly larger in both 45° and CD compared to MD. Both fracture characteristics and strain field distributions differed between the three material directions. Significant fibre reorientation was an active deformation mechanism in 45° already from the beginning of the loading, also present in CD after peak load but absent in MD. The MD‐dependent mechanisms interpreted and quantified at the scale of the fibre network in this study can help guide model development and likely have wider applicability to other paper‐based materials. [ABSTRACT FROM AUTHOR]

Important connections in representation theory arise from resolving a finite-dimensional algebra by an endomorphism algebra of a generator-cogenerator with finite global dimension; for instance, Auslander's correspondence, classical Schur–Weyl duality and Soergel's Struktursatz. Here, the module category of the resolution and the module category of the algebra being resolved are linked via an exact functor known as the Schur functor. In this paper, we investigate how to measure the quality of the connection between module categories of (projective) Noetherian algebras, B, and module categories of endomorphism algebras of generator-relative cogenerators over B which are split quasi-hereditary Noetherian algebras. In particular, we are interested in finding, if it exists, the highest degree n so that the endomorphism algebra of a generator-cogenerator provides an n-faithful cover, in the sense of Rouquier, of B. The degree n is known as the Hemmer–Nakano dimension of the standard modules. We prove that, in general, the Hemmer–Nakano dimension of standard modules with respect to a Schur functor from a split highest weight category over a field to the module category of a finite-dimensional algebra B is bounded above by the number of non-isomorphic simple modules of B. We establish methods for reducing computations of Hemmer–Nakano dimensions in the integral setup to computations of Hemmer–Nakano dimensions over finite-dimensional algebras, and vice-versa. In addition, we extend the framework to study Hemmer–Nakano dimensions of arbitrary resolving subcategories. In this setup, we find that the relative dominant dimension over (projective) Noetherian algebras is an important tool in the computation of these degrees, extending the previous work of Fang and Koenig. In particular, this theory allows us to derive results for Schur algebras and the BGG category \mathcal {O} in the integral setup from the finite-dimensional case. More precisely, we use the relative dominant dimension of Schur algebras to completely determine the Hemmer–Nakano dimension of standard modules with respect to Schur functors between module categories of Schur algebras over regular Noetherian rings and module categories of group algebras of symmetric groups over regular Noetherian rings. We exhibit several structural properties of deformations of the blocks of the Bernstein-Gelfand-Gelfand category \mathcal {O} establishing an integral version of Soergel's Struktursatz. We show that deformations of the combinatorial Soergel's functor have better homological properties than the classical one. [ABSTRACT FROM AUTHOR]