Engineering Fracture Mechanics最新文献_第6页

An anisotropic eigenfracture approach accounting for mixed fracture modes in wooden structures by the Representative Crack Element framework 各向异性特征断裂法，通过代表性裂缝要素框架考虑木结构中的混合断裂模式

IF 4.7 2区工程技术 Q1 MECHANICS

Engineering Fracture Mechanics

Pub Date : 2024-10-24 DOI: 10.1016/j.engfracmech.2024.110572

Marcel May, Daniel Konopka, Johannes Storm, Michael Kaliske

Finite Element analysis of anisotropic fracture phenomena in wood is a challenging task, particularly when dealing with intricate loading scenarios and mode-specific behavior. The appeal of energetically motivated approaches, such as the eigenfracture method, is that they enable simulation of fracture without prior knowledge of the crack path. The promising eigenfracture method has shown good numerical performance for isotropic materials, and this contribution showcases its application to anisotropic materials. Wood is one such anisotropic material and in this manuscript, the directional dependence of both elasticity and fracture evolution are incorporated into the eigenfracture approach. Further, the eigenfracture approach is used in conjunction with Representative Crack Elements (RCE), which permit accurate modeling of physical crack deformations. The governing equations are systematically derived and implemented into the Finite Element framework. By representative numerical examples, some advantages over the alternative phase-field method are demonstrated. Another highlight of this work is that it is possible to provide a realistic ratio of the energy release rates parallel to and perpendicular to the fiber direction in order to achieve physically accurate crack patterns. Additionally, the calculation effort is reduced, because the unknowns required to determine the crack kinematics can be solved analytically at the material level, a feature that also enables parallelization.

对木材各向异性断裂现象进行有限元分析是一项具有挑战性的任务，尤其是在处理复杂的加载情况和特定模式行为时。以能量为动机的方法（如特征断裂法）的吸引力在于，它们可以在不事先了解裂纹路径的情况下模拟断裂。前景广阔的特征断裂法已在各向同性材料中显示出良好的数值性能，本文将展示其在各向异性材料中的应用。木材就是这样一种各向异性材料，在本手稿中，弹性和断裂演化的方向依赖性都被纳入了特征断裂方法。此外，特征断裂法还与代表裂缝元素（RCE）结合使用，从而可以准确模拟物理裂缝变形。在有限元框架中系统地推导并实施了控制方程。通过具有代表性的数值示例，展示了相场法相对于其他方法的一些优势。这项工作的另一个亮点是可以提供平行于纤维方向和垂直于纤维方向的能量释放率的实际比率，从而实现物理上精确的裂纹模式。此外，由于确定裂纹运动学所需的未知数可以在材料层面上进行分析求解，从而减少了计算工作量，这一特点也使得并行化成为可能。

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引用次数: 0

A strain transmissibility-based analysis approach for operational modal of concrete dam under nonstationary excitation 基于应变传递率的非稳态激励下混凝土大坝运行模态分析方法

IF 4.7 2区工程技术 Q1 MECHANICS

Engineering Fracture Mechanics

Pub Date : 2024-10-24 DOI: 10.1016/j.engfracmech.2024.110581

Zheng Fang , Huaizhi Su , Shenglong Zuo , Shuai Zhang

The transmissibility-based operational modal analysis (TOMA) method is attracting more attentions due to its relaxation of assumptions about excitation properties, making accurately identifying the modes of actual engineering structures possible. However, in specific application on distributed vibration responses of huge hydraulic structures excited by broad-spectrum non-stationary earthquake, more proper selections of data segmentations on two dimensions (along time or spatial axis) are needed. Based on the concept of distributed vibration sensing optical fiber strain transmissibility, the operational modal analysis model based on single reference and poly references transmissibility under the strain format and the corresponding solutions of model and modal parameters are studied. A false mode elimination method combined with the continuity of spatial distribution of optical fiber measurements, a response sequence set optimization method that comprehensively consider amplitude/PSD non-stationarity, and the principle about how to select (non) reference points (sets) considering the spatial distribution of measurement signal-to-ratio are further developed. The case study shows that the proposed combined method could improve the modal parameter identification accuracy of concrete dams under broad-spectrum non-stationary excitation, and the distributed optical fiber vibration sensing technology can provide a rich (non) reference point (set) selection combination for this method.

基于传递率的运行模态分析（TOMA）方法由于放宽了对激励特性的假设，使得准确识别实际工程结构的模态成为可能，因而受到越来越多的关注。然而，在具体应用于广谱非稳态地震激发的巨大水工结构的分布式振动响应时，需要在两个维度（沿时间轴或空间轴）上对数据分割进行更恰当的选择。基于分布式振动传感光纤应变透射率的概念，研究了应变格式下基于单参考和多参考透射率的运行模态分析模型，以及相应的模型和模态参数解。进一步发展了结合光纤测量空间分布连续性的假模消除方法、综合考虑振幅/PSD 非稳态的响应序列集优化方法，以及考虑测量信比空间分布的（非）参考点（集）选择原则。案例研究表明，所提出的组合方法可提高混凝土大坝在宽谱非稳态激励下的模态参数识别精度，而分布式光纤振动传感技术可为该方法提供丰富的（非）参考点（集）选择组合。

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引用次数: 0

Multiscale image-based modeling for failure prediction of sheet molding compound composite under uniaxial tension 基于多尺度图像的薄片模塑复合材料单轴拉伸失效预测模型

IF 4.7 2区工程技术 Q1 MECHANICS

Engineering Fracture Mechanics

Pub Date : 2024-10-23 DOI: 10.1016/j.engfracmech.2024.110582

Li Yang , Hongye Zhang , Shuhan Ren , Kaifeng Wang , Jingjing Li

Carbon fiber reinforced polymer (CFRP) composites are extensively utilized as primary load-bearing components in various engineering applications due to their superior strength-to-weight ratio and excellent mechanical properties. However, their intricate microstructural interactions within composite present a significant challenge for failure analysis of CFRP. Although finite element (FE) simulations have been proven feasible to conduct the failure analysis, the classical FE models are developed based on homogeneous fiber characteristics, ignoring the influence of internal structures on the damage evolution process. This paper presents a multiscale image-based modeling approach to predict the tensile failure procedure of chopped carbon fiber sheet molding compound (SMC) composite. To accurately reconstruct the representative volume element (RVE) model of the SMC composite, synchrotron micro-X-ray computed tomography (μXCT) was adapted to explore the SMC internal microstructure. Then microscale RVE models with different fiber volume fractions were constructed to predict the corresponding microcosmic mechanical properties, which were used as the inputs for mesoscale RVE models to determine the constitutive parameters of fiber chips having varied fiber volume and orientations. Finally, the YOLOv5_Seg algorithm was employed to extract the geometric feature parameters of the fiber chips for mesoscale RVE modeling and then the failure location and sequence under uniaxial tension were predicted. It is found that the final simulated failure behaviors were consistent with the experimental observations, confirming the feasibility of this approach for understanding the failure mechanisms of CFRP composites. Thus, once the internal microstructure is determined using experimental techniques or predicted by simulating the composite manufacturing process, this approach can also be utilized for design optimization and performance evaluation for CFRP composites.

碳纤维增强聚合物（CFRP）复合材料因其优越的强度重量比和出色的机械性能，被广泛用作各种工程应用中的主要承重部件。然而，复合材料内部错综复杂的微结构相互作用给 CFRP 的失效分析带来了巨大挑战。尽管有限元（FE）模拟已被证明是进行失效分析的可行方法，但经典的 FE 模型是基于同质纤维特性开发的，忽略了内部结构对损伤演变过程的影响。本文提出了一种基于多尺度图像的建模方法，用于预测切碎碳纤维片状模塑料（SMC）复合材料的拉伸破坏过程。为了准确重建 SMC 复合材料的代表体积元素（RVE）模型，采用同步辐射微 X 射线计算机断层扫描（μXCT）技术来探索 SMC 的内部微观结构。然后构建了具有不同纤维体积分数的微观 RVE 模型，以预测相应的微观力学性能，并将其作为中观 RVE 模型的输入，以确定具有不同纤维体积和取向的纤维芯片的构成参数。最后，采用 YOLOv5_Seg 算法提取纤维屑的几何特征参数用于中尺度 RVE 模型，然后预测单轴拉伸下的破坏位置和顺序。结果发现，最终模拟的失效行为与实验观察结果一致，证实了这种方法在理解 CFRP 复合材料失效机理方面的可行性。因此，一旦利用实验技术确定了内部微观结构，或通过模拟复合材料制造过程预测了内部微观结构，这种方法也可用于 CFRP 复合材料的设计优化和性能评估。

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引用次数: 0

Extracting ductile cast iron microstructure parameters from fracture surfaces: A deep learning based instance segmentation approach 从断裂面提取球墨铸铁微观结构参数：基于深度学习的实例分割方法

IF 4.7 2区工程技术 Q1 MECHANICS

Engineering Fracture Mechanics

Pub Date : 2024-10-23 DOI: 10.1016/j.engfracmech.2024.110586

Johannes Rosenberger , Johannes Tlatlik , Carla Beckmann , Benedikt Rohrmüller , Sebastian Münstermann

This study investigates the deep-learning based microstructural analysis from SEM images of ductile cast iron fracture surfaces. A Mask R-CNN model was trained, achieving 70% precision and 75% recall in graphite particle detection. Combined with a fracture surface reconstruction using the.

4-quadrant backscattered electron signal, key parameters, including the particle size, shape and distance were extracted accurately. Compared to micrograph analysis, following probabilistic simulations showed the impact of the higher microstructural variance for the fracture surfaces on crack initiation, leading to higher scatter and elevated crack resistance curves. This highlights the potential of deep-learning based analysis for comprehensive microstructural characterization.

本研究探讨了基于深度学习的球墨铸铁断口表面扫描电镜图像微观结构分析。研究人员训练了一个 Mask R-CNN 模型，该模型在石墨颗粒检测方面达到了 70% 的精确度和 75% 的召回率。结合使用 4象限反向散射电子信号进行的断裂表面重构，可以精确提取包括颗粒大小、形状和距离在内的关键参数。与显微照片分析相比，后续的概率模拟显示了断裂表面较高的微观结构差异对裂纹起始的影响，从而导致较高的散度和较高的裂纹阻力曲线。这凸显了基于深度学习的分析在综合微结构表征方面的潜力。

引用次数: 0

Fatigue crack growth in functionally graded materials using an adaptive phase field method with cycle jump scheme 使用带周期跳跃方案的自适应相场法研究功能分级材料中的疲劳裂纹生长

IF 4.7 2区工程技术 Q1 MECHANICS

Engineering Fracture Mechanics

Pub Date : 2024-10-23 DOI: 10.1016/j.engfracmech.2024.110573

Hirshikesh , S. Natarajan , Ean Tat Ooi

Functionally graded materials provide versatility in adjusting the volume fractions of constituent materials to meet specific design requirements. However, this customization often introduces mode-mixity at the crack tip, posing challenges in predicting fracture under cyclic loading with discrete approaches and computationally expensive with conventional phase-field fracture models. To address these issues, this paper introduces an adaptive phase-field fracture formulation with cycle jump scheme to elegantly predict fatigue crack nucleation and growth in functionally graded materials. Within this framework, the effective properties at a point are estimated using the Mori–Tanaka homogenization scheme, while the crack growth due to cyclic load is captured by incorporating an additional fatigue degradation parameter. Moreover, the computational efficiency of the proposed framework is improved through an adaptive mesh refinement and explicit cycle jump scheme. The adaptive refinement scheme utilizes an error indicator derived from both the displacement solution and phase-field variable. The adaptive refinement scheme is integrated with efficient quadtree decomposition, which generates a hierarchical mesh structure. Hanging nodes resulting from the quadtree decomposition are efficiently handled using a polygonal finite element method. The proposed framework is validated against experimental and numerical results reported in the literature. Furthermore, we investigate the fatigue crack growth resistance across a broad range of material gradation directions, gaining valuable insights and identifying functionally graded materials with high fatigue resistance.

功能分级材料在调整组成材料的体积分数以满足特定设计要求方面具有多功能性。然而，这种定制往往会在裂纹顶端引入模态混杂性，从而给采用离散方法预测循环加载下的断裂带来挑战，而且传统的相场断裂模型计算成本高昂。为了解决这些问题，本文介绍了一种带有周期跳跃方案的自适应相场断裂公式，以优雅地预测功能分级材料中疲劳裂纹的成核和生长。在此框架内，使用 Mori-Tanaka 均质化方案估算某点的有效属性，同时通过加入额外的疲劳退化参数来捕捉循环载荷导致的裂纹增长。此外，通过自适应网格细化和显式循环跳转方案，提高了拟议框架的计算效率。自适应细化方案利用从位移解决方案和相场变量中得出的误差指标。自适应细化方案与高效的四叉树分解相结合，可生成分层网格结构。四叉树分解产生的悬挂节点通过多边形有限元方法得到有效处理。根据文献报道的实验和数值结果，对提出的框架进行了验证。此外，我们还研究了各种材料分级方向的抗疲劳裂纹生长能力，从而获得了宝贵的见解，并确定了具有高抗疲劳能力的功能分级材料。

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引用次数: 0

Experimental and numerical studies on the propagation paths of gear root cracks 齿轮根部裂纹扩展路径的实验和数值研究

IF 4.7 2区工程技术 Q1 MECHANICS

Engineering Fracture Mechanics

Pub Date : 2024-10-22 DOI: 10.1016/j.engfracmech.2024.110583

Haifeng He , Liangyu Zhao , Jiahong Huang , Heli Liu , Yuhong Yuan

Gear bending fatigue failure has a significant impact on the operational performance of advanced machinery, such as electric vehicles and wind turbines, potentially leading to failures and catastrophic consequences for transmission systems. Several methods are currently used to predict gear crack propagation; however, a comprehensive comparison of their accuracy and efficiency in predicting crack paths is lacking. In this study, the propagation path of root cracks in commonly used automotive gears was investigated using finite element (FE) analysis and experimental testing. Three mixed crack path prediction criteria were integrated to predict the gear root crack propagation using the commercial software ABAQUS by user-defined Python script. The impacts of gear crack parameters, including the gear initial crack length, on gear root crack propagation behaviour were analysed. The simulations were verified by the gear bending fatigue test using a single tooth bending test device. The results indicate that the simulation outcomes align with the experimental tests, demonstrating that all three criteria are effective in predicting gear root crack propagation behaviours.

齿轮弯曲疲劳失效对电动汽车和风力涡轮机等先进机械的运行性能有重大影响，可能导致传动系统失效并造成灾难性后果。目前，有几种方法可用于预测齿轮裂纹的扩展，但缺乏对其预测裂纹路径的准确性和效率的全面比较。在本研究中，我们使用有限元（FE）分析和实验测试对常用汽车齿轮根部裂纹的扩展路径进行了研究。通过用户自定义的 Python 脚本，使用商业软件 ABAQUS 综合了三种混合裂纹路径预测标准来预测齿轮根部裂纹的扩展。分析了齿轮裂纹参数（包括齿轮初始裂纹长度）对齿轮根部裂纹扩展行为的影响。模拟结果通过使用单齿弯曲试验装置进行的齿轮弯曲疲劳试验进行了验证。结果表明，模拟结果与实验测试结果一致，表明所有三个标准都能有效预测齿轮根部裂纹扩展行为。

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引用次数: 0

Investigation of fracture mechanical properties of a brass alloy with microstructural variations 研究具有微观结构变化的黄铜合金的断裂机械性能

IF 4.7 2区工程技术 Q1 MECHANICS

Engineering Fracture Mechanics

Pub Date : 2024-10-22 DOI: 10.1016/j.engfracmech.2024.110564

Martin Benedikt Klaushofer, Michael Stoschka, Bernd Maier, Florian Grün

This study investigates the effect of microstructural variations on the mechanical properties of CuZn35Mn2Al1Fe1-C-GS brass alloy. Specimens taken from positions with different cooling rates in a large cast component exhibit coarse-grained (approximately 5 mm) and fine-grained (approximately 1 mm) microstructures. Fine-grained samples demonstrate at least a 7% increase in Ultimate Tensile Strength (UTS) and up to a 33% higher long crack threshold

Δ K_{th,lc}

. Hardness measurements are similar between microstructures. The NASGRO model and cyclic R-curve are applied to fit crack propagation data, and fractographic analysis reveals distinct fracture mechanisms. The results indicate that a fine-grained microstructure enhances tensile strength and crack resistance, providing valuable insights for the design and maintenance of heavy machinery components made from cast brass.

本研究探讨了微观结构变化对 CuZn35Mn2Al1Fe1-C-GS 黄铜合金机械性能的影响。从大型铸造部件中不同冷却速度位置取出的试样呈现出粗粒（约 5 毫米）和细粒（约 1 毫米）两种微观结构。细粒样品的极限拉伸强度 (UTS) 至少提高了 7%，长裂纹阈值 ΔKth,lc 最多提高了 33%。不同微结构的硬度测量结果相似。应用 NASGRO 模型和循环 R 曲线来拟合裂纹扩展数据，断口分析揭示了不同的断裂机制。结果表明，细粒度微观结构提高了抗拉强度和抗裂性，为黄铜铸件重型机械部件的设计和维护提供了有价值的见解。

引用次数: 0

Coupling algorithm of cavity expansion theory and finite element for penetrating reinforced concrete 穿透式钢筋混凝土的空腔膨胀理论与有限元耦合算法

IF 4.7 2区工程技术 Q1 MECHANICS

Engineering Fracture Mechanics

Pub Date : 2024-10-20 DOI: 10.1016/j.engfracmech.2024.110580

Chenglong Huang , Zhenqing Wang , Shutao Li , Yeqing Chen , Mengnan Dai , Wei Wu , Wanli Wei , Jiazheng Gao , Qingyuan Yang

Aiming at the dynamic problem of projectile penetrating reinforced concrete, this paper creatively proposes a coupling algorithm combining cavity expansion theory and the finite element method. This approach effectively resolves the problem of low efficiency in finite element simulations while ensuring computational accuracy. In this study, based on the cavity expansion theory, we have redeveloped the display dynamics software. Radial stress in the concrete is applied to the warhead surface in the normal direction, and the interaction between the projectile and the steel bar is simulated using the finite element contact algorithm. A coupling algorithm has been developed that can stably and quickly simulate the penetration of reinforced concrete by a projectile. The study indicates that the implementation of the coupling algorithm primarily includes four steps: model establishment and meshing, stress load program design, load application, and initial condition setting. Through verification and analysis, the coupling algorithm presented in this paper is demonstrated to effectively compute the dynamic response of a projectile during penetration. It exhibits superior computational stability and speed compared to the finite element method, and shows minimal sensitivity to grid size. When applied to numerical models with small meshes, it achieves both high precision and rapid computation. The coupling algorithm program design proposed in this paper can be implemented in any display dynamics software, offering a robust approach for engineers and researchers to predict projectile penetration effects. Furthermore, it provides a rapid assessment method for the anti-penetration performance of reinforced concrete structures.

针对弹丸穿透钢筋混凝土的动力学问题，本文创造性地提出了空腔膨胀理论与有限元法相结合的耦合算法。这种方法在保证计算精度的前提下，有效解决了有限元模拟效率低的问题。在本研究中，我们以空腔膨胀理论为基础，重新开发了显示动力学软件。将混凝土中的径向应力沿法线方向施加到弹头表面，利用有限元接触算法模拟弹丸与钢筋之间的相互作用。开发的耦合算法可以稳定、快速地模拟弹丸穿透钢筋混凝土的过程。研究表明，耦合算法的实施主要包括四个步骤：模型建立和网格划分、应力载荷程序设计、载荷施加和初始条件设置。通过验证和分析，本文提出的耦合算法可以有效计算抛射体在穿透过程中的动态响应。与有限元方法相比，该算法具有更高的计算稳定性和速度，并且对网格大小的敏感性极低。当应用于小网格的数值模型时，它可以实现高精度和快速计算。本文提出的耦合算法程序设计可在任何显示动力学软件中实现，为工程师和研究人员预测弹丸穿透效应提供了一种稳健的方法。此外，它还为钢筋混凝土结构的抗穿透性能提供了一种快速评估方法。

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引用次数: 0

Extension of the GISSMO fracture model for thin-walled structures under combined tensile and bending loads 在拉伸和弯曲综合载荷作用下薄壁结构的 GISSMO 断裂模型的扩展

IF 4.7 2区工程技术 Q1 MECHANICS

Engineering Fracture Mechanics

Pub Date : 2024-10-20 DOI: 10.1016/j.engfracmech.2024.110574

Pawel B. Woelke , Juan G. Londono , Tobias Erhart , André Haufe , Sebastijan Jurendic , David Anderson

Ductile fracture prediction for thin-walled structures requires computationally efficient simulation tools able to approximately represent the key effects that occur on the sub-thickness scale. Unfortunately, classical shell elements, typically used to model deformation and failure of thin components, are inherently in a state of plane stress and therefore unable to capture the through-thickness stress distribution. This is consequential considering recent studies that demonstrated the differences between fracture in bending vs. in-plane tension. A laterally constrained thin metal plate under in-plane tension is likely to fracture under significantly lower plastic strain than the same plate under bending (with fracture initiating on the tensile side), even though both these conditions are examples of plane strain tension. Under in-plane tension fracture is preceded by a through-thickness neck, and therefore higher stress triaxiality than in the case of plane strain bending, where necking is absent. To account for these differences, we propose an extension of the GISSMO model, which relies on a simple fracture criterion based on stress-dependent fracture strain defined by the user (i.e. fracture locus). The fracture strain is typically determined experimentally using a combination of in-plane tensile tests under varying degree of lateral constraint and shear tests. The proposed extension involves defining a separate fracture locus for bending, also determined experimentally using bending tests. Fracture occurs when the equivalent plastic strain reaches its critical level represented by interpolation between the two bounding cases, i.e. bending and in-plane tension, with a bending index Ω used as an interpolation parameter.

薄壁结构的韧性断裂预测需要计算效率高的模拟工具，这些工具能够近似表示发生在亚厚度尺度上的关键效应。遗憾的是，通常用于模拟薄壁部件变形和断裂的经典壳元素本质上处于平面应力状态，因此无法捕捉到通厚应力分布。考虑到最近的研究证明了弯曲断裂与平面拉伸断裂之间的差异，这一点非常重要。在平面内受拉的横向约束金属薄板，其断裂时的塑性应变可能明显低于在弯曲状态下的同一块薄板（断裂始于受拉一侧），尽管这两种情况都属于平面应变拉伸。在平面拉伸条件下，断裂前会出现通厚颈，因此应力三轴性比平面应变弯曲条件下的应力三轴性要高，因为平面应变弯曲条件下不会出现颈缩。为了解释这些差异，我们提出了对 GISSMO 模型的扩展，该模型依赖于一个简单的断裂准则，该准则基于用户定义的应力依赖性断裂应变（即断裂位置）。断裂应变通常是通过实验确定的，结合使用不同程度横向约束下的面内拉伸试验和剪切试验。拟议的扩展包括定义单独的弯曲断裂位点，也是通过弯曲试验进行实验确定的。当等效塑性应变达到临界水平时，即发生断裂，该临界水平由两种约束情况（即弯曲和平面内拉伸）之间的插值表示，弯曲指数Ω用作插值参数。

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引用次数: 0

Investigating the influence of geometric configurations and loading modes on mixed mode I/II fracture characteristics of rocks: Part I-Numerical simulation 研究几何构造和加载模式对岩石 I/II 混合模式断裂特性的影响：第一部分--数值模拟

IF 4.7 2区工程技术 Q1 MECHANICS

Engineering Fracture Mechanics

Pub Date : 2024-10-20 DOI: 10.1016/j.engfracmech.2024.110575

Longfei Wang , Huan Liu , Xiaoping Zhou

The influence of geometric configurations and loading modes is a bottleneck that restricts the accurate determination of rock fracture parameters and the precise understanding of fracture mechanisms. Therefore, the phase field method is employed to analyze the influences of specimen geometry and loading modes on the dimensionless stress intensity factors, peak load, fracture toughness, and crack initiation angle during the rock mixed mode I/II fracture process. Three new configurations of specimens are proposed to test rock mixed mode I/II fracture. The research results indicate that as the prefabricated crack inclination angle increases, the peak load of three-point bending type specimen increases, while the peak load of diametric-compression type specimen decreases. Moreover, the influence of geometric configurations on the fracture parameters of three-point bending specimens is greater than that of diametric-compression disk specimens. The research findings of this work can provide basic supporting data for the establishment of mixed mode I/II fracture testing standards.

几何构型和加载模式的影响是制约岩石断裂参数精确测定和断裂机理准确理解的瓶颈。因此，采用相场法分析了岩石 I/II 混合模式断裂过程中试样几何构型和加载模式对无量纲应力强度因子、峰值载荷、断裂韧性和裂纹起始角的影响。针对岩石 I/II 混合模式断裂测试，提出了三种新的试样配置。研究结果表明，随着预制裂纹倾角的增大，三点弯曲型试样的峰值载荷增大，而直径压缩型试样的峰值载荷减小。此外，几何构造对三点弯曲试样断裂参数的影响大于直径压缩盘试样。该研究成果可为建立 I/II 混合模式断裂测试标准提供基础支持数据。

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引用次数: 0