Engineering Fracture Mechanics最新文献

The Capriccio method as a versatile tool for quantifying the fracture properties of glassy materials under complex loading conditions with chemical specificity Capriccio方法是一种多功能的工具，用于量化玻璃材料在复杂载荷条件下的断裂特性，具有化学特异性

IF 5.3 2区工程技术 Q1 MECHANICS

Engineering Fracture Mechanics

Pub Date : 2026-01-13 DOI: 10.1016/j.engfracmech.2026.111841

Felix Weber , Maxime Vassaux , Lukas Laubert , Sebastian Pfaller

Molecular dynamics (MD) simulations are widely used to provide insights into fracture mechanisms while maintaining chemical specificity. However, particle-based techniques such as MD are limited in terms of accessible length scales and applicable boundary conditions, which restricts the investigation of fracture phenomena in typical engineering settings. In an attempt to overcome these limitations, we apply the partitioned-domain Capriccio method to couple atomistic MD samples representing silica glass with the finite element (FE) method. With this approach, we perform mode I (rectangular panel under tension, three-, and four-point bending), mode II as well as mode III (rectangular panel under in-plane or out-of-plane shear) simulations. Thereby, we investigate multiple criteria to identify the onset of crack propagation based on the virial stress, the number of pair interactions, the kinetic energy/temperature, the crack velocity, and the crack opening displacement. It becomes apparent that the maximum virial stress can actually serve as an objective and meaningful indicator for the start of crack growth, in contrast to, for example, the temperature evolution The approach presented provides quantitatively plausible results for the critical stress intensity factors

K_{Ic}

,

K_{IIc}

, and

K_{IIIc}

. This contribution shows that the Capriccio method is a flexible means of performing fracture simulations that take into account boundary conditions typical of experimental test setups with atomistic specificity near the crack tip. While also pointing out the current limitations of the Capriccio method, we demonstrate its potential to integrate atomistic insights into FE models with significantly larger overall dimensions.

分子动力学（MD）模拟被广泛用于在保持化学特异性的同时提供对裂缝机制的深入了解。然而，基于颗粒的技术（如MD）在可获得的长度尺度和适用的边界条件方面受到限制，这限制了典型工程环境中裂缝现象的研究。为了克服这些限制，我们应用分域Capriccio方法将原子MD样品与有限元（FE）方法耦合在一起。通过这种方法，我们执行模式I（矩形面板在张力，三点和四点弯曲下），模式II和模式III（矩形面板在面内或面外剪切下）模拟。因此，我们研究了基于维里应力、对相互作用次数、动能/温度、裂纹速度和裂纹张开位移的多重准则来识别裂纹扩展的开始。很明显，与温度演变等因素相比，最大虚拟应力实际上可以作为裂纹扩展开始的客观和有意义的指标。本文提出的方法为临界应力强度因子KIc， KIIc和KIIIc提供了定量可信的结果。这表明，Capriccio方法是一种灵活的断裂模拟方法，它考虑了裂纹尖端附近具有原子特异性的实验测试设置的典型边界条件。在指出Capriccio方法目前的局限性的同时，我们展示了它将原子的洞察力集成到具有更大总体维度的FE模型中的潜力。

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引用次数: 0

Fatigue life prediction of metal rubber under small-sample conditions via data augmentation and physics-informed fusion 基于数据增强和物理信息融合的小样本条件下金属橡胶疲劳寿命预测

IF 5.3 2区工程技术 Q1 MECHANICS

Engineering Fracture Mechanics

Pub Date : 2026-01-13 DOI: 10.1016/j.engfracmech.2026.111865

Zihao Huang , Zhiying Ren , Han Lin , Yuedan Li , Chunhui Zhou , Xianbao Xiang , Jinhui Chen

Metal rubber (MR), as a novel elastic porous material, has been widely applied in critical fields such as aerospace, and its fatigue life prediction is of great significance for ensuring equipment safety. To address the dual challenges of data scarcity and complex physical mechanisms in life modeling of MR, this paper proposes a fatigue life prediction method that integrates data augmentation with physics-informed modeling—namely, the GAN-PILM-TCN model. Specifically, a Wasserstein Generative Adversarial Network (W-GAN) is first employed to augment the limited fatigue test data, effectively alleviating the problem of insufficient samples. Then, stiffness and damping damage factors are incorporated into the modeling process to enhance the physical interpretability of the model. In addition, Principal Component Analysis (PCA) is applied to reduce the dimensionality of multi-dimensional features and extract key information on damage evolution. Furthermore, a hybrid loss function is constructed based on the Weibull distribution to guide the model in better capturing the relationship between fatigue damage and life during training. Experimental results demonstrate that the proposed method achieves a significant improvement in prediction performance under small-sample conditions, with a maximum R² of 0.9336. To further evaluate model stability, 10 independent training runs were conducted, yielding an average mean squared error of MSE_avg = 0.0142 and a standard deviation of Std = 0.0011, indicating good stability and reproducibility. These findings provide a new methodological framework and technical support for fatigue life prediction and reliability design of MR under complex operating conditions.

金属橡胶作为一种新型的弹性多孔材料，已广泛应用于航空航天等关键领域，其疲劳寿命预测对保障设备安全具有重要意义。为了解决MR寿命建模中数据稀缺和物理机制复杂的双重挑战，本文提出了一种将数据增强与物理信息建模相结合的疲劳寿命预测方法，即GAN-PILM-TCN模型。具体而言，首先采用Wasserstein生成对抗网络（W-GAN）对有限的疲劳试验数据进行扩充，有效缓解了样本不足的问题。然后，将刚度和阻尼损伤因素纳入建模过程，以增强模型的物理可解释性。此外，应用主成分分析（PCA）对多维特征进行降维，提取损伤演化的关键信息。此外，基于威布尔分布构造了混合损失函数，以指导模型更好地捕捉训练过程中疲劳损伤与寿命的关系。实验结果表明，该方法在小样本条件下的预测性能有显著提高，最大R2为0.9336。为了进一步评价模型的稳定性，我们进行了10次独立训练，平均均方误差为MSEavg = 0.0142，标准差为Std = 0.0011，表明模型具有良好的稳定性和重复性。研究结果为复杂工况下磁流变器的疲劳寿命预测和可靠性设计提供了新的方法框架和技术支持。

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引用次数: 0

On the mixed mode crack propagation using a 2D BEM formulation combined with a Newton-Raphson/Arc-length iterative method: discussion about material bifurcation 结合牛顿-拉夫森/弧长迭代法的二维边界元公式研究混合模式裂纹扩展：关于材料分岔的讨论

IF 5.3 2区工程技术 Q1 MECHANICS

Engineering Fracture Mechanics

Pub Date : 2026-01-12 DOI: 10.1016/j.engfracmech.2026.111858

Gabriela R. Fernandes , Eduardo A. de Souza Neto , José J.C. Pituba

Numerical modeling of mixed mode cracks propagation is discussed by using a 2D Boundary Element formulation with Quadratic convergence applied to Strong Discontinuities (BEMQ-SD). This model is based on strong discontinuity technique embedded into a continuum medium. The criterion for material bifurcation is the singularity of the acoustic tensor, being the normal direction to the crack surface defined by its eigenvalue. Usually only one direction is related to this singularity, but we discuss examples where we can have two different directions associated with the material bifurcation. Thus, we propose an efficient criterion to identify the correct solution. The Arc-length method combined with the Newton-Raphson method is adopted to obtain the solution of the iterative procedure required to solve the equilibrium problem. This force control procedure is efficient and has low computational cost, achieving the solution with a small number of iterations. As numerical examples, we consider a plate with a fragile sub-domain subjected to pure shear and to a combination of loads, a single-edge notched shear test and two experimentally tested examples, which present a mixed-mode fracture configuration with multiple cracks. We show that the proposed model can find the correct solution, and it is accurate, stable and efficient, showing itself to be an alternative tool to FEM or XFEM models. An important advantage of BEM models is that is not necessary to discretize the domain that remains with elastic behavior, what reduces the computational effort.

采用二维强不连续二次收敛边界元公式，讨论了混合模式裂纹扩展的数值模拟。该模型基于嵌入连续介质的强不连续技术。材料分叉的判据是声张量的奇异性，即由其特征值定义的到裂纹表面的法向。通常只有一个方向与这个奇点有关，但我们讨论的例子中，我们可以有两个不同的方向与材料分岔有关。因此，我们提出了一个有效的标准来识别正确的解决方案。采用弧长法结合牛顿-拉夫逊法求解平衡问题所需的迭代过程。该力控制程序效率高，计算成本低，迭代次数少。作为数值算例，我们考虑了具有脆性子域的板在纯剪切和组合载荷作用下，单边缺口剪切试验和两个实验测试实例，它们呈现出多重裂纹的混合模式断裂形态。仿真结果表明，所提出的模型能够找到正确的解，且精度高、稳定性好、效率高，可作为有限元模型或XFEM模型的替代工具。边界元模型的一个重要优点是不需要对保持弹性行为的区域进行离散化，从而减少了计算量。

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引用次数: 0

Three-dimensional fracture evolution in coal under cryogenic-thermal shock based on CT technology 基于CT技术的低温-热冲击下煤体三维裂隙演化

IF 5.3 2区工程技术 Q1 MECHANICS

Engineering Fracture Mechanics

Pub Date : 2026-01-12 DOI: 10.1016/j.engfracmech.2026.111861

Lei Qin , Chengang Sun , Xian Zhang , Niandong Chen , Weikai Wang , Feilong Zhang , Meiling Xiong

The pore structure of coal plays a crucial role in the migration of fluids such as gas and water. To analyze the evolution law and deterioration mechanisms of the three-dimensional pore structure in coal subjected to cryogenic-thermal cyclic shock, this study employed three-dimensional CT scanning technology to investigate the impact of the number of cryogenic-thermal shock cycles on coal pore structure parameters. The results indicate that: (1) The number of three-dimensional pores in coal increases with the number of cryogenic-thermal shock cycles. (2) Pore evolution undergoes three irreversible stages: damage accumulation (0–6 cycles), network reconstruction (7–9 cycles), and fragmentation equilibrium (10–12 cycles). The pore shape factor decreases to a minimum of 0.015, while the coordination number peaks at 32. (3) After 12 cycles, the pore-throat structure exhibits highly discrete characteristic radii (45, 105, and 135 μm), each accounting for ∼ 33.3 %, forming an efficient hierarchical seepage network. (4) Based on the characteristics of microscopic damage evolution in coal, cryogenic-thermal cycling synergistically disrupts the coal structure through a triple-mechanism (comprising dynamic pressure shock, thermal stress cycling, and multiphase phase-change damage). This research enriches the fundamental theory of cryogenic-thermal cyclic shock (LCO₂ − high-temperature steam) on coal.

煤的孔隙结构对气、水等流体的运移起着至关重要的作用。为分析低温-热循环冲击作用下煤体三维孔隙结构的演化规律及恶化机制，本研究采用三维CT扫描技术研究低温-热循环次数对煤体孔隙结构参数的影响。结果表明：(1)煤中三维孔隙数量随着低温-热冲击循环次数的增加而增加。(2)孔隙演化经历3个不可逆阶段：损伤积累（0 ~ 6个旋回）、网络重构（7 ~ 9个旋回）和破碎平衡（10 ~ 12个旋回）。孔隙形状因子最小为0.015，配位数最大为32。(3)经过12次循环后，孔喉结构表现出高度离散的特征半径（45、105和135 μm），每个特征半径占~ 33.3%，形成了一个高效的分层渗透网络。(4)根据煤体微观损伤演化特征，低温-热循环通过动压冲击、热应力循环和多相相变损伤三重机制协同破坏煤体结构。该研究丰富了煤的低温-热循环冲击（LCO2 -高温蒸汽）的基础理论。

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引用次数: 0

Influence of printing orientation of Inconel 718 specimens on LEFM parameters analyzed via DVC 用DVC分析了印模取向对印模参数的影响

IF 5.3 2区工程技术 Q1 MECHANICS

Engineering Fracture Mechanics

Pub Date : 2026-01-12 DOI: 10.1016/j.engfracmech.2026.111849

Malo Valmalle , Gaëtan Touzé , Benjamin Smaniotto , Nicolas Muller , Joseph Marae Djouda , François Hild

Laser powder bed fusion (LPBF) is an additive manufacturing technique that enables for the production of metallic parts with complex geometries, and the possibility of locally adapting mesostructures. This study aims at determining the influence of hatch angle and build orientation on Linear Elastic Fracture Mechanics (LEFM) parameters of specimens obtained by LPBF. In the present work, the mechanical response of mini CT specimens made of Inconel 718 alloy obtained by LPBF were studied when subjected to in-situ tensile loading. The LEFM parameters of the different specimens were extracted from displacement fields measured with Digital Volume Correlation (DVC) using Williams’ fields. The crack front and Stress Intensity Factors (SIF) profiles of the different experiments were analyzed. The extracted LEFM parameters for the different specimens displayed significant differences in Young’s Modulus and fracture toughness due to variations in build orientation.

激光粉末床熔融（LPBF）是一种增材制造技术，能够生产具有复杂几何形状的金属零件，并有可能局部适应介孔结构。本研究旨在确定舱口角度和构建方向对LPBF获得的试样线弹性断裂力学（LEFM）参数的影响。本文研究了LPBF法制备的Inconel 718合金微型CT试样在原位拉伸载荷作用下的力学响应。利用Williams场，从数字体积相关（Digital Volume Correlation， DVC）测量的位移场中提取不同试件的LEFM参数。分析了不同试验条件下的裂纹前缘和应力强度因子分布。由于构建方向的不同，所提取的不同试样的LEFM参数在杨氏模量和断裂韧性方面存在显著差异。

引用次数: 0

Estimating the fracture properties of Martian rocks based on microscale rock mechanical experiments and probability model 基于微尺度岩石力学实验和概率模型的火星岩石断裂特性估计

IF 5.3 2区工程技术 Q1 MECHANICS

Engineering Fracture Mechanics

Pub Date : 2026-01-10 DOI: 10.1016/j.engfracmech.2026.111850

Shuohui Yin , Yingjie Wang , Yiheng Zhang , Linling Li , Jinggang Liu , Shuitao Gu

The human space exploration activities on Mars, such as space observation stations and scientific research, etc., need the support of planetary geotechnical theory. Due to the rarity and arbitrary shapes of Martian rock samples, it is difficult to obtain their probability distribution of mechanical properties through the macroscale rock mechanics experiments (macro-RME) with standard samples. In this work, a novel and effective probabilistic method was proposed to estimate the probability distribution of mechanical and fracture properties of Martian rocks through the microscale rock mechanical experiments (micro-RME), probability model and energy-based method combined with the mechanical property correlation. Firstly, the minerals of the NWA12564 Martian meteorite were analyzed through the TESCAN Integrated Mineral Analyzer (TIMA) and grid nanoindentation tests. The optimal probability distribution of fracture toughness (

K_{C}

) was obtained through the Kolmogorov-Smirnov (K-S) test and an energy method. Secondly, the probability distribution of macroscale fracture toughness (

K_{IC}

) was derived by an upscaling method and Monte Carlo simulations (MCS). Thirdly, the probability distributions of tensile strength (

TS

) and unconfined compressive strength (

UCS

) were estimated by the mechanical property correlations with the macroscale fracture toughness

K_{IC}

. The research also indicated that, while the macroscale mechanical and fracture properties of Martian rocks follow a lognormal distribution, the microscopic fracture toughness of the five minerals may follow distinct probability distributions. The proposed method enables the estimation of the probability distribution of mechanical and fracture properties with arbitrarily shaped and sized Martian rocks, and the obtained properties provide support to the future Mars exploration.

人类在火星上的空间探索活动，如空间观测站和科学研究等，都需要行星岩土理论的支持。由于火星岩石样品的稀有性和任意形状，用标准样品进行宏观岩石力学实验（macro-RME），很难获得其力学性质的概率分布。通过微观岩石力学实验（micro-RME）、概率模型和基于能量的方法，结合力学性质相关性，提出了一种估算火星岩石力学和断裂性质概率分布的新颖有效的概率方法。首先，通过TESCAN集成矿物分析仪（TIMA）和网格纳米压痕测试对NWA12564火星陨石的矿物进行了分析。通过Kolmogorov-Smirnov （K-S）试验和能量法得到断裂韧性（KC）的最佳概率分布。其次，采用上标方法和蒙特卡罗模拟（MCS），推导了宏观断裂韧性（KIC）的概率分布。第三，通过力学性能与宏观断裂韧性KIC的相关关系，估计了抗拉强度和无侧限抗压强度的概率分布。研究还表明，火星岩石的宏观力学和断裂性质服从对数正态分布，而五种矿物的微观断裂韧性可能服从不同的概率分布。该方法能够估计任意形状和大小的火星岩石的力学和断裂性质的概率分布，为未来的火星探测提供支持。

{"title":"Estimating the fracture properties of Martian rocks based on microscale rock mechanical experiments and probability model","authors":"Shuohui Yin , Yingjie Wang , Yiheng Zhang , Linling Li , Jinggang Liu , Shuitao Gu","doi":"10.1016/j.engfracmech.2026.111850","DOIUrl":"10.1016/j.engfracmech.2026.111850","url":null,"abstract":"<div><div>The human space exploration activities on Mars, such as space observation stations and scientific research, etc., need the support of planetary geotechnical theory. Due to the rarity and arbitrary shapes of Martian rock samples, it is difficult to obtain their probability distribution of mechanical properties through the macroscale rock mechanics experiments (macro-RME) with standard samples. In this work, a novel and effective probabilistic method was proposed to estimate the probability distribution of mechanical and fracture properties of Martian rocks through the microscale rock mechanical experiments (micro-RME), probability model and energy-based method combined with the mechanical property correlation. Firstly, the minerals of the NWA12564 Martian meteorite were analyzed through the TESCAN Integrated Mineral Analyzer (TIMA) and grid nanoindentation tests. The optimal probability distribution of fracture toughness (<span><math><mrow><msub><mi>K</mi><mi>C</mi></msub></mrow></math></span>) was obtained through the Kolmogorov-Smirnov (K-S) test and an energy method. Secondly, the probability distribution of macroscale fracture toughness (<span><math><mrow><msub><mi>K</mi><mrow><mi>IC</mi></mrow></msub></mrow></math></span>) was derived by an upscaling method and Monte Carlo simulations (MCS). Thirdly, the probability distributions of tensile strength (<span><math><mrow><mi>TS</mi></mrow></math></span>) and unconfined compressive strength (<span><math><mrow><mi>UCS</mi></mrow></math></span>) were estimated by the mechanical property correlations with the macroscale fracture toughness <span><math><mrow><msub><mi>K</mi><mrow><mi>IC</mi></mrow></msub></mrow></math></span>. The research also indicated that, while the macroscale mechanical and fracture properties of Martian rocks follow a lognormal distribution, the microscopic fracture toughness of the five minerals may follow distinct probability distributions. The proposed method enables the estimation of the probability distribution of mechanical and fracture properties with arbitrarily shaped and sized Martian rocks, and the obtained properties provide support to the future Mars exploration.</div></div>","PeriodicalId":11576,"journal":{"name":"Engineering Fracture Mechanics","volume":"333 ","pages":"Article 111850"},"PeriodicalIF":5.3,"publicationDate":"2026-01-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145973630","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Enhanced cellulose paper interfaces with MWCNT/Graphene for improved structural health monitoring and mechanical performance in CARALL 增强纤维素纸与MWCNT/石墨烯的界面，以改善CARALL的结构健康监测和机械性能

IF 5.3 2区工程技术 Q1 MECHANICS

Engineering Fracture Mechanics

Pub Date : 2026-01-10 DOI: 10.1016/j.engfracmech.2026.111857

Tugay Üstün , Ebru Saraloğlu Güler , Volkan Eskizeybek

Carbon fiber reinforced aluminum laminates (CARALL) suffer from weak metal–composite interfaces and the lack of built-in damage sensing. Here, cellulose paper interleaves loaded with hybrid multi-walled carbon nanotubes (CNTs) and graphene (5–9 wt% at 160 or 210 g/m²) are fabricated by conventional papermaking and inserted at the Al/CFRP interface. CARALL panels were produced via hand lay-up and vacuum bagging and evaluated under tensile, three-point flexural, and Mode-I fracture tests, with damage events monitored in situ through piezoresistive electrical resistance measurements (ΔR/R). The 210 g/m² paper with 9 wt% hybrid nanofiller maintains baseline tensile strength and yields up to ∼ 20 % higher flexural strength versus unreinforced CARALL, while interlaminar fracture toughness increases during both initiation and propagation. Microscopic observations reveal fiber bridging/pull-out and crack deflection within the paper interlayer, while the formation of a percolated CNT/graphene network enables clear piezoresistive responses. Abrupt ΔR/R jumps were observed at final failure under tensile loading (approximately twofold), whereas event-correlated ΔR/R fluctuations were recorded during flexural and Mode-I fracture tests (typically in the range of ∼ 0.25–2 during flexure and − 0.5 to + 0.5 during double cantilever beam tests). The results demonstrate that lightweight, low-cost cellulose-nanocarbon interleaves simultaneously toughen CARALL and provide integrated structural health monitoring capability.

碳纤维增强铝层压板（CARALL）存在金属复合界面薄弱和缺乏内置损伤传感的问题。通过传统的造纸工艺，将纤维素纸与混合多壁碳纳米管（CNTs）和石墨烯（5-9 wt%， 160或210 g/m2）交织在一起，并插入Al/CFRP界面。CARALL面板通过手工铺层和真空装袋生产，并在拉伸、三点弯曲和i型断裂测试下进行评估，并通过压阻电阻测量（ΔR/R）现场监测损伤事件。210 g/m2的混合纳米填料与未增强的CARALL相比，可保持基线抗拉强度，并产生高达20%的抗弯强度，而在起始和扩展过程中，层间断裂韧性均有所增加。微观观察显示，纸张夹层内的纤维桥接/拉出和裂纹偏转，而碳纳米管/石墨烯网络的渗透形成实现了清晰的压阻响应。在拉伸载荷下的最终破坏时，观察到突然的ΔR/R跳变（大约两倍），而在弯曲和i型断裂试验期间，记录到事件相关的ΔR/R波动（通常在弯曲期间为- 0.25-2范围内，在双悬臂梁试验期间为- 0.5至+ 0.5）。结果表明，轻质、低成本的纤维素-纳米碳交织材料同时增强了CARALL的韧性，并提供了集成的结构健康监测能力。

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引用次数: 0

A novel boundary displacement decomposition method for stress intensity factor calculation in 2D inclined crack 一种计算二维倾斜裂纹应力强度因子的边界位移分解方法

IF 5.3 2区工程技术 Q1 MECHANICS

Engineering Fracture Mechanics

Pub Date : 2026-01-10 DOI: 10.1016/j.engfracmech.2026.111859

Sanshao Zhuang , Tao Hu , Junfeng Zhang , Wenqing Zheng , Miaolin Feng

For a 2D inclined crack, a novel boundary displacement decomposition method based on the submodel technique and using circular harmonic (CH) as basis functions is proposed to calculate the stress intensity factor (SIF). This method computes the SIF by linearly superimposing the precomputed SIF values of the basis functions and the decomposition coefficients of the submodel boundary displacement, which are obtained from finite element analysis (FEA). The approach circumvents the computationally intensive task of generating crack meshes in the global model during analysis. Specifically, CH functions are employed as the basis functions for submodel boundary displacement decomposition. A dimensionless stress intensity factor (s-SIF) is derived, and a workflow based on FEA is established for the precomputation of the s-SIFs of the basis functions. The s-SIFs for the first eight orders of the CH basis functions are precomputed. Finally, the relationship between the SIF prediction accuracy and the submodel domain size is examined, and a numerical example from NASGRO is used to validate the proposed method.

针对二维倾斜裂纹，提出了一种基于子模型技术、以圆谐波为基函数的边界位移分解方法来计算应力强度因子。该方法通过将有限元分析得到的基函数和子模型边界位移分解系数的预先计算的SIF值线性叠加来计算SIF。该方法避免了在分析过程中在全局模型中生成裂纹网格的计算量大的任务。具体而言，采用CH函数作为子模型边界位移分解的基函数。推导了无量纲应力强度因子，建立了基于有限元分析的无量纲应力强度因子预计算流程。CH基函数的前八阶s- sif是预先计算的。最后，分析了SIF预测精度与子模型域大小之间的关系，并用NASGRO的一个数值算例验证了该方法的有效性。

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引用次数: 0

Dynamic compressive behavior and constitutive parameters of chemically strengthened aluminosilicate glass 化学强化铝硅酸盐玻璃的动态压缩性能及本构参数

IF 5.3 2区工程技术 Q1 MECHANICS

Engineering Fracture Mechanics

Pub Date : 2026-01-10 DOI: 10.1016/j.engfracmech.2026.111844

Ruimin Yang, Jing Ling, Xingya Su, Lin Jing

Quasi-static and dynamic compressive mechanical experiments of chemically strengthened aluminosilicate glass (CSAG) were conducted, using an electronic universal testing machine and a split Hopkinson pressure bar (SHPB) apparatus over a wide strain rate range of 0.0001 s⁻¹ to 1700 s⁻¹. Parallel to these, plate impact experiments were performed using a single-stage light gas gun to determine the material’s Equation of State (EOS) under high-pressure shock compression. For the quasi-static and SHPB tests, the failure processes were captured using high-speed photography to understand macroscopic failure mechanisms; additionally, post-test fragments were analyzed via scanning electron microscopy (SEM) and statistical methods to characterize fragment size distribution and micro-crack morphology under various strain rates. Finally, the Johnson-Holmquist (JH-2) constitutive parameters of the CSAG were then calibrated by integrating the EOS derived from plate impact data with the strength and damage characteristics obtained from the compressive tests. Numerical simulations were conducted to validate the accuracy of determined model parameters. The experimental results show that CSAG exhibits significant brittle fracture characteristics with strain-rate sensitivity in compressive strength. The fracture mechanism transforms from the flaw-dominated single-crack growth under quasi-static loading to a multiple-cracking phenomenon under dynamic loading. In both regimes, cracks propagate along the loading direction, with final explosive fragmentation caused by their coalescence under transverse tensile stresses. The distribution of fragment sizes provides a quantitative characterization of this shift in fracture mechanisms: a non-linear relationship between mass ratio and fragment size is observed under quasi-static loading, whereas dynamic loading (1100 s⁻¹ and 1700 s⁻¹) yields a distinctly linear correlation, where the mass ratio increases as fragment size decreases. This transition reflects the intensified fragmentation and rapid energy dissipation induced by high strain rates. The plate impact experimental data provides the essential pressure–volume relationship for the JH-2 model. The numerical simulations show good agreement with experimental observations, confirming that the calibrated model accurately.

在0.0001 s−1 ~ 1700 s−1的应变速率范围内，利用电子万能试验机和霍普金森压杆（SHPB）装置对化学强化铝硅酸盐玻璃（CSAG）进行了准静态和动态压缩力学实验。与此同时，使用单级光气枪进行板冲击实验，以确定高压冲击压缩下材料的状态方程（EOS）。在准静态和SHPB试验中，采用高速摄影捕捉破坏过程，了解宏观破坏机制；此外，通过扫描电子显微镜（SEM）和统计学方法对测试后的碎片进行分析，表征不同应变速率下的碎片尺寸分布和微裂纹形貌。最后，通过整合从板冲击数据中获得的EOS与从压缩试验中获得的强度和损伤特征，对CSAG的Johnson-Holmquist （JH-2）本构参数进行校准。通过数值模拟验证了模型参数的准确性。试验结果表明，CSAG具有明显的脆性断裂特征，对抗压强度具有应变率敏感性。断裂机制由准静态加载下以缺陷为主的单裂纹扩展转变为动态加载下的多裂纹扩展。在这两种情况下，裂纹沿加载方向扩展，在横向拉应力作用下，裂纹聚并导致最终爆炸破碎。碎片大小的分布为这种断裂机制的转变提供了定量表征：准静态加载下，质量比和碎片大小之间呈非线性关系，而动态加载（1100 s−1和1700 s−1）产生明显的线性相关性，其中质量比随着碎片大小的减小而增加。这种转变反映了高应变率引起的破碎加剧和能量快速耗散。平板撞击实验数据为JH-2模型提供了必要的压力-体积关系。数值模拟结果与实验结果吻合较好，证实了标定模型的准确性。

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引用次数: 0

Mechanical properties and damage evolution of fissured sandstone under cyclic gradient loading with an increasing lower stress limit 应力下限值增大的循环梯度加载下裂隙砂岩力学性能及损伤演化

IF 5.3 2区工程技术 Q1 MECHANICS

Engineering Fracture Mechanics

Pub Date : 2026-01-07 DOI: 10.1016/j.engfracmech.2026.111839

Yunqiang Wang , Kang Peng , Zhenyu Wang , Yushuai Zhang , Yang Wu , Chunhai Li

Rock masses subjected to repeated geological processes commonly contain structural planes, such as joints and cracks. Under disturbance loads such as blasting excavation or mechanical drilling, the mechanical properties of fissured rock degrade to varying degrees, ultimately leading to instability and failure of the engineering. Based on this, cyclic gradient loading tests with an increasing lower stress limit were conducted on sandstone samples with cracks at different angles using the MTS 815 rock mechanics testing system and the PCI-2 acoustic emission (AE) instrument. The study investigated the mechanical properties, acoustic emission characteristics, and the evolution of damage variables in fissured sandstone under complex stress conditions. The results show that, during cyclic gradient loading with an increasing lower stress limit, the stress–strain behavior of fissured sandstone is closely related to its deformation characteristics and exhibits a distinct step-like pattern. In the loading stages near failure, internal microcracks rapidly propagate, leading to significant deformation of the fissured sandstone. The stress–strain curve displays a clear “sparse-intensive-sparse” characteristic. The crack angle has a significant influence on the peak stress, exhibiting a clear linear relationship between the two. With an increase in the crack angle, the failure mode of fissured sandstone shifts from predominantly tensile-shear cracking to shear cracking, and eventually to interlayer shear failure. AE count rate and AE energy rate effectively reflect the development of internal damage in fissured rock. Both parameters show a significant increase during the first cycle of each loading stage and in the cycles approaching failure. Analysis of the RA-AF characteristic parameters indicates that, with increasing crack angle, the proportion of shear cracks in the failure mode of fissured sandstone increases. This trend is generally consistent with the macroscopic crack coalescence patterns observed in the samples. A damage variable was defined based on dissipated energy density, and its evolution law was established. The service life of fissured sandstone was also predicted, with all prediction results showing a confidence level above 93%, providing a valuable reference for the life prediction of fissured sandstone under cyclic gradient loading.

经过反复地质作用的岩体通常包含结构面，如节理和裂缝。在爆破开挖或机械钻孔等扰动荷载作用下，裂隙岩体的力学性能会发生不同程度的退化，最终导致工程失稳和破坏。在此基础上，利用MTS 815岩石力学测试系统和PCI-2声发射（AE）仪，对不同角度裂缝的砂岩试样进行了应力下限递增的循环梯度加载试验。研究了复杂应力条件下裂隙砂岩的力学特性、声发射特征及损伤变量演化规律。结果表明：在应力下限不断增大的循环梯度加载过程中，裂隙砂岩的应力-应变行为与其变形特征密切相关，呈现出明显的阶梯状模式；在接近破坏的加载阶段，内部微裂纹迅速扩展，导致裂隙砂岩发生显著变形。应力-应变曲线表现出明显的“稀疏-密集-稀疏”特征。裂纹角度对峰值应力有显著影响，两者呈明显的线性关系。随着裂隙角度的增大，裂隙砂岩的破坏模式由主要的拉剪破坏向剪切破坏转变，最终向层间剪切破坏转变。声发射计数率和声发射能率能有效反映裂隙岩石内部损伤的发展情况。在每个加载阶段的第一个循环和接近破坏的循环中，这两个参数都有显著的增加。对RA-AF特征参数的分析表明，随着裂缝角度的增大，剪切裂缝在裂隙砂岩破坏模式中所占比例增大。这一趋势与试样中观察到的宏观裂纹合并模式基本一致。定义了基于耗散能量密度的损伤变量，并建立了其演化规律。对裂隙砂岩的寿命进行了预测，预测结果置信度均在93%以上，为循环梯度荷载作用下裂隙砂岩的寿命预测提供了有价值的参考。

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