Deformation Analysis Research Articles

HexagonRingCalculator: A Handy Code for Hexagonal Ring Characterization in Atomistic Simulations.

Hexagonal rings are critical to the properties of many nanomaterials by determining their mechanical strength, thermal stability, and electrical conductivity, therefore this kind of structure has been intensively concerned in computational studies. However, existing molecular dynamics (MD) simulation tools lack specialized functions for identifying and characterizing them. To address this gap, we developed HexagonRingCalculator, a tool for identifying hexagonal rings and calculating their geometric properties, including bond lengths, ring area, and circularity, directly from MD simulation data. The code facilitates the analysis of ring deformation under varying conditions, such as temperature changes. We demonstrate its functionality and accuracy through classic and ab initio MD simulations of graphene and cellulose, highlighting its potential to advance computational studies in nanomaterials.

Stone instance segmentation of rubble masonry based on laser scanning point clouds

Laser scanning allows for objective area-based analysis of water dam structures to enable targeted interventions in case of displacements, requiring comparison of the same areas over different epochs. This comparison improves if identical areas, e.g. stones, from multiple epochs can be automatically derived in advance. We present an instance segmentation algorithm based on a 3D point cloud with reflected intensity information to identify individual stones in rubble masonry dams that can be used within deformation monitoring. The algorithm uses initial k-means classification followed by image-based processing steps, resulting in a segmented 3D point cloud with individual stones. It is evaluated against a manually labeled reference and analyzed on terrestrial laser scanning (TLS) and UAV-based data sets. Correctly identified stones are 89.92% for TLS and 90.82% for UAV data. Additionally, stone centroids and shapes were evaluated without significant deviation. A first outlook on deformation analysis was provided using ICP matching of stones from two simulated epochs.

Direct energy deposition for smart micro reactor

ABSTRACT Nuclear microreactors (MRs) have attracted significant attention for their versatility in installation locations, especially with the growing demand for sustainable green energy in large data processing facilities. However, ensuring their safe operation necessitates frequent inspections, which can be challenging for practical efficient management. This study proposes a novel approach using direct energy deposition to incorporate an optical fiber sensor into MR components, enabling real-time monitoring with artificial intelligence. The embedded optical fiber generates real-time data that allows for AI-driven in-vivo thermal deformation analysis. Our smart MR component can detect structural anomalies, identify abnormal operations, and assess operational conditions through augmented reality interfaces and AI technology.

Thermal-deformation behaviors of the primary sealants in double, triple, and multi glazed insulating glass units

Polyisobutylene (PIB), commonly used as the primary sealant of double, triple, and multi glazed insulating glass units (IGUs), provides the key moisture barrier function and determines the expected lifespan of the IGUs and even the entire glass curtain wall systems (GCWSs). Slipping and debonding of the PIB, caused by temperature changes, have resulted in numerous instances of premature failure of building envelopes. However, available research is inadequate in accurately evaluating the service environment of IGUs and thermal-deformation behaviors of this energy-saving building material. This paper presented a simplified method for analyzing the thermal environment of IGUs, considering outdoor air temperature, solar radiation, wind speed, and angle to the horizontal. A numerical modeling method was proposed and validated with the heat transfer tests. Three finite element (FE) models were built and utilized for the precise analysis of temperature-induced deformations of double, tripled, and quadruple glazed IGUs. Simplified calculation formulas for the maximum thermal deformation of PIB in the X and Y directions under different temperature conditions were obtained, taking a new concept “cavity-to-pane ratio” into consideration. Finally, the relationship between the PIB’s temperature-induced deformation and its probability was proposed. The results show that the IGUs in Beijing suffer more than 22 % of their time in harsh service conditions where the difference between indoor and outdoor temperatures exceeds 20 °C. For DIGUs, the maximum temperature-induced deformations of the PIB in X (along the short side of the panel) and Y (along the long side of the panel) directions are 0.142 and 0.214 mm, respectively, corresponding to shear strains of 28.4 % and 42.8 % for the PIB with a thickness of only 0.5 mm. For TIGUs, the maximum deformations increase to 0.159 and 0.239 mm, corresponding to shear strains of 31.8 % and 47.8 %. For QIGUs and the other multi-glazed IGUs, these values can increase to 36.8 % and 55.4 % or more. The methodology proposed in this paper aims to lay the groundwork for further addressing premature failure issues and optimizing edge bond constructions of multi-glazed IGUs.

Atomistic insights into scratch-induced structural evolution of silica glass

Understanding the mechanism of scratch damage is vital to developing better scratch-resistant glasses. To this extent, employing molecular dynamics simulations and experiments, we investigate the scratch damage of silica glass against a rigid diamond indenter. The glass surface is pre-indented to a constant depth and then dragged to simulate a linear scratch, and the structural impact in the indent-to-scratch transitioning phase is examined. We observe that despite the differences in length and timescales, the simulated values of indentation hardness and coefficient of friction exhibit excellent agreement with experimental values from nanoindentation and atomic force microscopy experiments. Interestingly, analysis of the subsurface deformation in the scratched region reveals densification and shear flow, in contrast to pure densification, as in the case of indentation. Furthermore, similar percentages of recovery from experiments and simulation reveal that the reversible component of plastic deformation owing to densification is comparable in both cases. Finally, in contrast to the common hypothesis, we demonstrate that while the bond angles and lengths recover significantly, the ring structure does not recover upon annealing, although they exhibit some relaxation. Thus, the present study sheds new light on the crucial role of the medium-range structure of glasses subjected to scratch deformation.

Prediction and Analysis of Surface Residual Deformation Considering the Impact of Groundwater in Mines

With economic development and coal resource exploitation, the area of mined-out zones is expanding continuously. The traditional waste disposal methods no longer meet the current demands, making it urgent to evaluate and reuse the surface stability of these mined-out zones. Surface residual deformation is a process where voids and fissures within the mined-out zones are gradually filled and compacted, affecting the overlying rock structure. Additionally, groundwater significantly impacts the strength of the overlying rock, leading to increased subsidence. Therefore, predicting surface residual deformation while considering the effects of groundwater is crucial for forecasting surface deformation and assessing stability in mined-out zones. This study, taking into account the characteristics of subsidence zones and the impact of groundwater on the compaction of fractured rock masses, uses equivalent mining height and probability integral methods to develop a predictive model for surface residual deformation incorporating groundwater effects. Predictions for the study area show that groundwater exacerbates surface residual deformation, with various deformation values ranging from 33.8% to 51.9%. The surface stability categories are divided into stable and essentially stable regions based on the residual deformation’s impact on the working face. This model fully considers the influence of groundwater on residual deformation in mined-out zones, refining existing mining subsidence theories, addressing deformation issues caused by adverse groundwater factors, and providing a theoretical basis for predicting residual deformation and evaluating stability in mined-out zones, promoting the sustainable development of land and environmental resources in mining areas.

Study of Deformations in Statically Indeterminate Beam in Industrial and Shipbuilding Structures

The paper considers the analysis of deformations in a statically indeterminate beam using the example of a ship's keel – an I-beam that plays an important role in ensuring the stability and structure of the vessel. The research is carried out through a combination of theoretical and experimental approaches. The force method was chosen for theoretical analysis as a universal tool for statically indeterminate beams, allowing to estimate deformations and stresses at various points of the beam. It includes the selection of the optimal cross section, which is an advantage of this approach. The finite element method (FEM), implemented using Ansys 2021 R2 PC, is used for experimental analysis and visualization of bending deformation. This method provides a more flexible and powerful tool for analyzing complex structures, taking into account a variety of boundary conditions. The results of the study were compared, and the calculation errors turned out to be minimal and acceptable. The paper emphasizes the importance of conducting such analyses to understand the behavior of structures under loads and ensure their reliability not only in transport, but also in industrial and civil construction.

Development of A Workshop on the Topic of the Bionically Inspired Lightweight Design Method for 3D Printed Components

Additive manufacturing methods, particularly 3D printing, are widely utilized in research and engineering for crafting lightweight yet durable materials capable of withstanding substantial forces. Leveraging insights from biomechanical structures offers a deeper understanding of reinforcement techniques and optimal design strategies to enhance strength. This paper focuses on the development of a Draisine design, historically significant in Karlsruhe, as part of the BWSplus project "Drais3D-Trinational" workshop. Through a comprehensive analysis of bionic influences on lightweight design and 3D printing parameters, this study aims to create an optimal design framework for the workshop. Utilizing Computer-Aided Design (CAD) software such as SolidWorks and Creo Parametric, along with Finite Element Analysis using ANSYS R2023 Workbench, deformation and stress analysis are conducted. Investigation into 3D printing parameters, including infill patterns, temperature, support systems, and orientation, seeks to identify optimal solutions considering factors like processing time, robustness, and filament wastage. The objective is to explore the biomechanical influence on construction methods, concept design, and parameter construction in preparation for the Drais3D-Trinational workshop in March 2023. The expected outcomes include the presentation of two main designs with varied parameters, alongside analyses such as Finite Element Analysis and optimization of 3D printing parameters, emphasizing the role of bionic structures in defining the optimal Draisine design.

Efficient Random Field Generation With Rotational Anisotropy for Probabilistic SPH Analysis of Slope Failure

ABSTRACTDue to geological processes such as sedimentation, tectonic movement, and backfilling, natural soil often exhibits characteristics of rotated anisotropy. Recent studies have shown the significant impact of rotated anisotropy on slope stability. However, little research has explored how this rotated anisotropy affects the large deformations occurring after slope failure. Therefore, this study integrates rotated random field theory with smoothed particle hydrodynamics (SPH) to investigate its influence on post‐failure slope behavior. Focusing on a typical slope scenario, this research utilizes graphics processing unit (GPU)–accelerated covariance matrix decomposition (CMD) method to create rotated anisotropy random fields and applies the SPH framework for analysis. It examines the influence of rotated anisotropy angles and the cross‐correlation between cohesion and internal friction angle on landslides. The results indicate that the rotational anisotropy of the slope significantly influences post‐failure behavior. When the rotation angle is close to the slope surface, it tends to amplify both the magnitude and variability of slope failure. Furthermore, the study evaluates the efficiency of generating these random fields and emphasizes the substantial computational speed improvements achieved with GPU acceleration. These findings offer a robust approach for probabilistic analysis of slope large deformations considering rotated anisotropy. They provide a theoretical foundation for accurately assessing the risk of slope collapse, holding significant practical implications for geotechnical engineering.

Smeared fixed crack model for quasi-static and dynamic biaxial flexural response analysis of aluminosilicate glass plates

Glass materials are extensively used in load-bearing structures and impact-resistant components because of their distinctive physical and chemical properties. Accurate predictions and assessment of the mechanical responses of glass structures are crucial for structural design and reliability analysis. In this study, quasi-static and dynamic ball-on-ring (BOR) biaxial flexural tests are conducted on aluminosilicate glass. The smeared fixed crack model is calibrated for deformation and failure analyses. First, the model parameters are calibrated carefully, particularly for different failure criteria. Both the deformation field and fracture modes agree well with the experimental observations during the quasi-static tests. For the low-velocity impact biaxial flexural loading condition, three different numerical techniques, namely the initial scaling tensile strength criterion, non-local approach with energy criterion, and rate-dependent failure stress criterion, are implemented in the numerical models for dynamic failure analysis. Finally, the proposed smeared fixed crack model is compared with the widely used Johnson Holmquist Ⅱ (JH-2) model and demonstrates advantages for low-velocity impact response analysis of glass structures.

Backward motion suppression in space-constrained piezoelectric pipeline robots

In response to the current challenges of detecting micro pipelines, a micro pipeline robot based on the principle of piezoelectric inertia stick-slip drive was proposed in this paper, which can be effectively applied to the detection and maintenance of micro pipelines. However, during the analysis of the robot's displacement trajectory, it was observed that using inertial drive could cause the backward motion of the robot. This may adversely affect the accuracy and stability of the robot's operation within the micro pipelines. Therefore, a novel control method is derived from the original pipeline robot structure. By affixing piezoelectric sheets to the driving feet of the robot to adjust their deformation and subsequently employing collaborative control of piezoelectric sheets and piezoelectric stacks to regulate friction between the driving feet and the pipe wall, the backward motion of the robot was effectively mitigated. Compared to existing backward motion suppression methods, the approach proposed in this paper has a minimal impact on the actuator's size, allowing for flexible adaptation to various space-constrained applications, while also offering the advantage of a simple control strategy. After determining the structure and working principle, deformation analysis of the driving foot and dynamic simulation analysis of the driving system were conducted. These analyses provide insights into the relationship between mechanical and electrical parameters and output performance within the driving system, thereby validating the feasibility of the control method. Subsequently, a prototype was fabricated, and its output performance was tested. Results demonstrate that this control method can effectively suppress inertial backward motion, achieving a suppression rate close to 100 %. This research presents a novel idea and methodology for mitigating the backward motion of piezoelectric inertial stick-slip actuators with driving foot structures.

Static analysis of foldable pressurized and thermally loaded cylindrical shell as an expander in sport equipment reinforced by G-Ori nanofillers

The present work investigates stress, strain and deformation analyses of a shear deformable cylindrical shell manufactures by a Copper (Cu) core reinforced with graphene origami auxetic metamaterial subjected to mechanical and thermal loads. The cylindrical models can be used in sport equipment especially in expander component. The effective material properties of the graphene origami auxetic reinforced Cu matrix are developed using micromechanical models cooperate both material properties of graphene and Cu in terms of local temperature, volume fraction and folding degree. The principle of virtual work is used to derive governing equations with accounting thermal loading.

Analysis of Excavation Methods Against Deformation in Highway Tunnels

Cisumdawu tunnel is a highway tunnelling which composed of very weak rock mass conditions has an average compressive strength less than 1 MPa. It is located below groundwater level. The shape of tunnell is horseshoe, diameter of tunnel section 14,413 m and height 11,083 m. Cisumdawu tunnel is a shallow tunnel which has a maximum overburden of 52,8 m and minimum overburden approximately 14 m. In the case of shallow tunnel which has a large section could be lead an instability during tunnel construction. Tunnel deformation analysis is using an observation and numerical modelling approach with finite element method which is assisted by RS 2019 (Rocscience) software. Based on the research is obtained that excavation method greatly affects the level of deformation that occurs during tunnel construction. As tunnelling advanced, Vertical displacement in the longitudinal direction using three bench seven step excavation method is smaller than full face and bench excavtion method. The maximum displacement using three bench excavation method is -4.23 mm, the full face method is -5.51 mm and the bench method is -4.91 mm. The amount of displacement is affected by the length of excavation and stage in tunnelling. The rate of deformation is increasing as the length of excavation getting deeper, but this is applied in unsupported tunnel.

Research on damage identification of wind power tower structure based on deformation and vibration dual parameter analysis

Abstract During the operation of the wind turbine, the force on the wind turbine tower is mainly caused by the vibration source at the top. As a high-rise structure with a large span, traditional vibration mechanics is used to analyze the overall force on the tower body, but the analysis of vibration modes or modes is slightly insufficient. This article adopts the analysis method of elastic wave dynamics to identify damage to the structure of wind power towers based on deformation and vibration dual parameter analysis. This article analyzes the propagation characteristics of elastic waves in tower structures, concrete bases, and foundation parts when damaged. This article develops a remote online monitoring and early warning platform for wind power tower bodies based on the attenuation properties of elastic waves. This article monitors the vibration and inclination of the tower drums of 5 wind turbines (# 13, # 31, # 34, # 49, and # 52). The tower drums have not undergone irreversible tilting or torsional deformation. However, through vibration analysis, it is suggested to check whether there is crushing between the tower drums and the concrete base, as well as whether there are local cracks on the surface of the concrete base. There may be local damage to the foundation ring of tower #31. It is recommended to check for local cracks in the foundation ring. This ensures the safe operation of wind power towers and has certain practical application value.

SEM-DIC characterization of the damage mechanism of an AlSi10Fe0.7 casting alloy on the microstructure scale

Various brittle phases are present in commercial cast aluminum alloys, which strongly influence their mechanical behavior. Among these, silicon precipitates are nearly omnipresent, as Si is a common alloying element. In secondary alloys, usually Fe-containing phases cannot be avoided, and they tend to degrade the mechanical properties. The interaction between the silicon phase and the failure-critical intermetallic phase in the Al-Si-Fe phase system (β-Al5FeSi) is studied in this paper in high resolution. A model alloy AlSi10Fe0.7 was defined, which is composed of a large grain Al-matrix, Si-precipitates and the plate-like β-Al5FeSi phase. The goal of the study was to identify “hot spots” in the microstructure from which cracks may initiate under mechanical loading. The main tool was a deformation analysis via digital image correlation in the SEM (SEM-DIC). This allows the identification and tracking of developing strain localizations at different potential crack initiation sites with a high resolution as well as capturing an overview over the whole specimen. An adapted frame averaging script minimized measurement errors induced by drift. The SEM-DIC results show that the deformation field is governed by the elastic incompatibility of the microstructural constituents. Crack initiation occurs because of the detachment of the Si + β-Al5FeSi phase boundary. Cracks then cross the phase boundary and propagate along twin boundaries in the β-Al5FeSi phase. Final failure is caused by linking fractured brittle plate-like particles.

Investigating compressed SAR technique efficiency for land deformation analysis along Hwanggang dam

Abstract Monitoring and determining the land deformation in dam reservoirs is very crucial as it is one of the main factors of dam failure around the world. Hwanggang Dam is located at a strategic location near the inter-Korean border. North Korea frequently released water from the Hwanggang Dam, which often triggers floods and landslides in areas near the inter-Korea border in South Korea. Consistent monitoring of the Hwanggang Dam is very crucial to avoid catastrophic loss of infrastructure and life. This research paper exploits the potential of the Compressed SAR (ComSAR) technique for deformation analysis along Hwanggang Dam. A total of 171 Sentinel-1 images of Hwanggang Dam were downloaded from Alaska Satellite Facility in ascending track acquired between 2016 and 2023 to generate a time-series interferogram stack. The generated interferogram stack was exploited by using the ComSAR technique to estimate deformation along Hwanggang Dam. The resultant estimated deformation shows instability along the Hwanggang Dam embarkment.

A novel FDEM-GSA method with applications in deformation and damage analysis of surrounding rock in deep-buried tunnels

In underground hydraulic tunnel engineering, particularlydeep-buried projects, the deformations and stability of the surrounding rock are critical to the construction process. Due to the complex depositional environment of such tunnels, multiple factors influence the stability of the surrounding rock during construction. This paper proposes a novel hybrid method combining Finite-Discrete Element Method (FDEM) with Global Sensitivity Analysis (GSA) and machine learning. The FDEM model is used to establish an approximate relationship between input and output parameters, and its accuracy is validated through comparison with monitoring data. On the basis of data simulated by the FDEM model, a meta-model is developed by Particle Swarm Optimization-Extreme Gradient Boosting (PSO-XGBoost). 10,000 data sets are generated using the meta-model for Sobol sensitivity analysis. The proposed analysis framework is applied to study the deep-buried water diversion tunnel in the Central Yunnan Water Diversion Project (CYWDP). The results indicate that in deep-buried tunnel environments, as the tunnel depth increases, the dominant factor influencing the deformation of the surrounding rock transitions from tunnel depth to the mechanical properties of the rock itself. These findings provide valuable insights for optimizing construction plans in similar tunnel projects and offer a new perspective on sensitivity analysis frameworks based on numerical computations.

Recycling single use surgical face mask waste for reinforcing cement-treated/untreated dredged marine sediments: Strength, deformation and micro-mechanisms analysis

To prevent the transmission of airborne infectious diseases (SARS, H1N1, COVID-19, and influenza), the use of disposable surgical face masks has increased dramatically in the past few years. To mitigate the environmental consequences associated with mask waste, implementing circular economy strategies with the reuse of mask waste is a sustainable method. This study explores an innovative way to reuse mask fiber (MF) with dredged sediment waste together as road construction materials. First, the MF was introduced into cement-treated/untreated dredged marine sediment mixtures with different content and lengths. Then, a variety of laboratory tests were carried out to explore the basic physical and chemical characterization of raw materials and the development of mechanical properties of mixtures. In addition, the intrinsic mechanism of MF inclusion on cement-treated sediments was analyzed by scanning electron microscope (SEM) test. The results show that the inclusion of MF significantly improves the unconfined compression strength (UCS) and splitting tensile strength (STS) of both treated and untreated specimens. The highest UCS and STS values are at the condition with an MF content of 0.25%, a length of MF of 2 cm, and a curing time of 28 days. The combined strength increase caused by cement-MF together inclusion is much greater than the strength increase caused by either of them separately. It was also found that the elastic modulus (E50) decreased with the inclusion of MF. Furthermore, the addition of MF changes the brittle behavior of the specimens, which also improves the ductility and residual strength of the specimens. The SEM analysis demonstrates the microstructure of MF and MF-reinforced specimens. The creation of a stable and interconnected microstructure is largely attributed to the bridging impact of MF and the binding effect of hydration products, which significantly improves the mechanical behavior of specimens. The MF-reinforced cement-treated sediment could be an innovative, environmentally friendly, and economical material for road construction.

Dynamic Analysis of Deformation of a Droplet on a Uniform Jet Surface

Dynamic Analysis of Deformation of a Droplet on a Uniform Jet Surface

Detecting active sinkholes through combination of morphometric-cluster assessment and deformation precursors

Sinkhole hazards pose considerable challenges in the west-central region of Texas. This study integrates multisource datasets and innovative techniques to detect early sinkhole development and identify the processes governing their formation. The techniques employed encompass feature extraction, cluster analysis, and deformation process monitoring. Potential sinkholes were initially mapped using high-resolution elevation data, and a circularity index (CI) threshold value of 0.85 was applied to filter out depressions with noncircular shapes. Subsequently, Persistent Scatterer Interferometry (PSInSAR) followed by the Getis-Ord Gi* statistic methods were used to identify statistically significant subsidence clusters with rates of <−2 mm/yr, indicating active sinkhole formation. The findings reveal the following: (1) surface deformation analysis revealed significant subsidence hotspots, particularly in areas underlain by units containing significant sequences of evaporites, which nominally belong to the Clear Fork Group and the Blaine Formation, compared with those dominated by carbonates; (2) potential sinkholes are undergoing displacement up to a rate of −11.31 mm/yr, and (3) extreme groundwater pumping of karst aquifers and the subsequent decline in groundwater levels are found to be the leading causes of the susceptibility of the region to sinkhole hazards. In such cases, the decline of the water table deprives the overlying bedrock of buoyant support provided by the groundwater in the cavity. The bedrock will undergo sagging subsidence under the influence of gravity and eventually form a sinkhole. Extensive oil and gas activity in the study area, including extreme withdrawal rates and the injection of fluids associated with the activity, are other potential causes of the observed sinkhole susceptibility in several parts of the study area. This study underscores the importance of understanding the geologic, hydrologic, and anthropogenic factors driving sinkhole hazards for effective mitigation strategies to protect public safety, infrastructure, and the environment.