Engineering Fracture Mechanics最新文献

Enhancing fracture resistance of concrete with hybrid micro–macro steel and polypropylene fibers under multiple failure modes: Experimental and reliability assessment 微宏钢-聚丙烯纤维复合材料增强混凝土多种破坏模式下的抗断裂性能：试验与可靠性评估

IF 5.3 2区工程技术 Q1 MECHANICS

Engineering Fracture Mechanics

Pub Date : 2026-01-31 DOI: 10.1016/j.engfracmech.2026.111882

Hamid Gorji , Behrooz Shirgir , Hamed Rooholamini , Mohammad Shamsi

This study presents a comprehensive experimental and statistical investigation into the fracture resistance of concrete reinforced with hybrid micro- and macro-scale steel and polypropylene fibers. Nine different fiber com inbinations were evaluated using Single-Edge Notched Beam (SENB) and Edge Notched Disc Bend (ENDB) specimens to measure fracture toughness under pure Mode I (tensile), Mode II (sliding), Mode III (tearing), and mixed-mode I/II loading. A two-parameter Weibull distribution was employed to assess the reliability and variability of the results. The findings demonstrate that hybrid fiber systems, particularly the combination of polypropylene micro-fibers and steel macro-fibers (PSSL), induce a significant synergistic effect, enhancing fracture toughness across all failure modes. The PSSL hybrid configuration increased the effective fracture toughness (K_eff) by up to 28.44% under mixed-mode I/II loading in SENB tests. Furthermore, the Weibull analysis revealed that hybrid fiber composites exhibit higher shape parameters, indicating more consistent and reliable fracture performance compared to plain and mono-fiber concrete. This study confirms that a multi-scale hybrid fiber reinforcement strategy is highly effective in improving the fracture resistance and structural reliability of concrete under complex stress states. Finally, Weibull analysis indicated that hybrid fiber systems exhibited higher shape parameters, reflecting more consistent and reliable fracture behavior than mono-fiber systems, which is critical for practical applications emphasizing mechanical performance consistency.

本文对钢和聚丙烯纤维微宏观混合配筋混凝土的抗断裂性能进行了全面的试验和统计研究。采用单边缘缺口梁（SENB）和边缘缺口盘弯曲（ENDB）试样对9种不同的纤维组合进行了评估，以测量纯模式I（拉伸）、模式II（滑动）、模式III（撕裂）和混合模式I/II加载下的断裂韧性。采用双参数威布尔分布来评估结果的可靠性和可变性。研究结果表明，混合纤维体系，特别是聚丙烯微纤维和钢宏纤维（PSSL）的组合，产生了显著的协同效应，提高了所有破坏模式下的断裂韧性。在SENB试验中，PSSL混合配置可使混合模式I/II加载下的有效断裂韧性（K_eff）提高28.44%。此外，Weibull分析显示，与普通和单纤维混凝土相比，混杂纤维复合材料具有更高的形状参数，表明其断裂性能更加一致和可靠。本研究证实了多尺度混杂纤维加固策略对于提高复杂应力状态下混凝土的抗断裂性能和结构可靠性是非常有效的。最后，Weibull分析表明，与单纤维系统相比，混杂纤维系统具有更高的形状参数，反映出更一致和可靠的断裂行为，这对于强调力学性能一致性的实际应用至关重要。

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引用次数: 0

Failure mechanism of unsaturated sandstone under freeze-thaw cycles: Critical saturation effect and segmented damage modeling 冻融循环作用下非饱和砂岩破坏机制：临界饱和效应和分段损伤模型

IF 5.3 2区工程技术 Q1 MECHANICS

Engineering Fracture Mechanics

Pub Date : 2026-01-29 DOI: 10.1016/j.engfracmech.2026.111902

Ziyi Yang , Ying Xu , Meilu Yu , Chengjie Li , Yingfu Li , Rongzhou Yang , Qiangqiang Zheng

The saturation state of rock, significantly influenced by its in-situ environment and precipitation, exhibits considerable variation at different depths or locations. This variation leads to distinct failure characteristics when the rock is subjected to loading, posing threats to engineering safety and economic development in cold regions. This study investigates the Yulong copper mine slope sandstone in Tibet, analyzing the failure behavior, micro-damage characteristics, and energy evolution patterns of rock under varying saturation states. A piecewise damage constitutive model is developed for freeze–thaw cycled rock at different saturation levels. The results demonstrate that increasing saturation leads to higher porosity, reduced cementing minerals, diminished mechanical properties, and a transition in failure mode towards complex shear failure. Based on energy analysis, the concept of a critical saturation degree for freeze–thaw rock is proposed. Within this range, the rock efficiently absorbs elastic energy without inducing excessive plastic deformation or crack propagation; exceeding this threshold results in rapid deterioration of mechanical properties. The differences in damage mechanisms for freeze–thaw rock at varying saturation levels are manifested in the meso-morphology and the compaction stage of the stress–strain curve. By analyzing the characteristics of dissipated energy, the compaction point and yield point are quantitatively characterized through the calculation of strain difference and its fluctuation characteristics, overcoming the limitations of subjective judgment. A piecewise constitutive model, established based on the Hoek-Brown criterion, accurately reflects the stage-dependent characteristics of freeze–thaw sandstone at different saturation levels and effectively characterizes the damage mechanism of unsaturated freeze–thaw sandstone.

岩石的饱和状态受原位环境和降水的影响较大，在不同深度或位置表现出较大的变化。这种变化导致岩石在受荷载作用下具有不同的破坏特征，对寒冷地区的工程安全和经济发展构成威胁。以西藏玉龙铜矿边坡砂岩为研究对象，分析岩石在不同饱和状态下的破坏行为、微损伤特征及能量演化规律。建立了不同饱和度下冻融循环岩石的分段损伤本构模型。结果表明，饱和度的增加导致孔隙度增加，胶结矿物减少，力学性能降低，破坏模式向复杂剪切破坏转变。在能量分析的基础上，提出了冻融岩石临界饱和度的概念。在此范围内，岩石有效地吸收弹性能，而不会引起过度的塑性变形或裂纹扩展；超过这个阈值会导致机械性能迅速恶化。冻融岩石在不同饱和度下损伤机制的差异表现在应力-应变曲线的细观形态和压实阶段。通过对耗散能特性的分析，通过计算应变差及其波动特性，对压实点和屈服点进行定量表征，克服了主观判断的局限性。基于Hoek-Brown准则建立的分段本构模型准确反映了冻融砂岩在不同饱和水平下的阶段依赖特征，有效表征了非饱和冻融砂岩的损伤机理。

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引用次数: 0

Numerical investigation on dynamic mechanical response of rock–backfill composites: Effect of interface angle and loading condition 填岩复合材料动态力学响应数值研究：界面角和加载条件的影响

IF 5.3 2区工程技术 Q1 MECHANICS

Engineering Fracture Mechanics

Pub Date : 2026-01-29 DOI: 10.1016/j.engfracmech.2026.111901

Zefeng Li , Aixiang Wu , Shaoyong Wang , Jiandong Wang

The dynamic mechanical behavior of rock–backfill coupling systems significantly impacts the stability of underground engineering structures. However, studies examining the dynamic mechanical response of rock–backfill composites under various interface angles and loading conditions are scarce. A coupled finite difference method (FDM)–discrete element method (DEM) numerical simulation approach was used to construct split Hopkinson pressure bar (SHPB) test systems and rock–backfill composite (RB) models. This study systematically investigated the effects of varying interface angles (0°, 30°, 45°, 60°, and 90°), impact velocities (4.0–8.5 m/s), and stress wave propagation directions (rock–to–backfill and backfill–to–rock) on the dynamic mechanical properties and damage evolution characteristics of the composites. The results show that peak stress first decreases, then increases with increasing interface angle. Peak stress reaches its maximum at 0° and its minimum at 45° or 60°. The peak strength of rock–to–backfill is significantly lower than that of backfill–to–rock, and the former is more sensitive to the strength–enhancing effect of increased impact velocity than the latter. At θ = 0° and 30°, both the backfill and rock exhibit significant damage. At θ = 45°, 60°, and 90°, crack initiation and propagation are primarily concentrated near the backfill or contact interface, with relatively low levels of rock damage. As the interface angle increases, the total number of cracks first decreases and then increases, with the dominant failure mode shifting from tensile cracks to shear cracks. Meanwhile, the displacement field shows that the damage at the interface changes from being mostly tensile to mostly shear. A displacement field partitioned by the contact interface develops within the RB. The impact velocity does not change the fundamental failure mode of the RB. Under high impact velocities, the crack behavior is characterized by “earlier initiation and stronger energy release”, with acoustic emission (AE) counts and discrete fragmentation increasing significantly. The research findings provide a theoretical foundation for the stability of underground rock engineering and disaster prevention.

岩石-充填体耦合系统的动力力学特性对地下工程结构的稳定性有重要影响。然而，针对不同界面角和加载条件下岩石-充填体复合材料动态力学响应的研究很少。采用有限差分法(FDM) -离散元法（DEM）耦合数值模拟方法，构建了霍普金森压杆（SHPB）劈裂试验系统和岩石充填体复合材料（RB）模型。系统研究了不同界面角（0°、30°、45°、60°和90°）、冲击速度（4.0 ~ 8.5 m/s）和应力波传播方向（岩石-充填体和充填体-岩石）对复合材料动态力学性能和损伤演化特征的影响。结果表明：随着界面角的增大，峰值应力先减小后增大；峰值应力在0°处最大，在45°或60°处最小。岩石对充填体的峰值强度明显低于充填体对岩石的峰值强度，并且前者对冲击速度增加的强度增强效应比后者更敏感。在θ = 0°和30°时，充填体和岩石均表现出明显的破坏。在θ = 45°、60°和90°时，裂纹萌生和扩展主要集中在充填体或接触界面附近，岩石损伤程度相对较低。随着界面角的增大，裂纹总数先减少后增加，主要破坏模式由拉伸裂纹向剪切裂纹转变。同时，位移场表明，界面处的损伤由以拉伸为主转变为以剪切为主。在RB内形成一个由接触界面划分的位移场。冲击速度不会改变RB的基本失效模式。在高冲击速度下，裂纹行为表现出“起裂早、能量释放强”的特征，声发射（AE）计数和离散破碎明显增加。研究结果为地下岩体工程的稳定性和灾害防治提供了理论依据。

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引用次数: 0

Effect of weld residual stress relaxation on evolutionary properties of multiple cracks in orthotropic steel deck 焊缝残余应力松弛对正交各向异性钢甲板多重裂纹演化特性的影响

IF 5.3 2区工程技术 Q1 MECHANICS

Engineering Fracture Mechanics

Pub Date : 2026-01-29 DOI: 10.1016/j.engfracmech.2026.111907

Honghao Wang , Naiwei Lu , Michael Brun , Wen Chen , Francis Praud , Yuan Luo , Yang Liu

Welding residual stress is a key factor leading to the initiation of multiple cracks in orthotropic steel decks. However, the effects of welding residual stress on evolutionary properties of multiple cracks in welded joints remain unclear. This study proposes a multiple cracks growth analysis method considering welding residual stress relaxation. Subsequently, the influence mechanism of welding residual stresses and multiple crack effects on fatigue life is investigated. Finally, the evolutionary properties of multiple cracks were revealed through experiments. The results show that fatigue life prediction result considering welding residual stress tend to yield conservative results, while incorporating its relaxation effects proves more consistent with experimental data. Welding residual stress accelerates the occurrence of multiple crack merging behavior. As crack depth increases, the effect of residual stresses on crack growth in the depth direction gradually decreases, while the merging behavior of multiple cracks becomes the critical driving force for structural fracture. Reverse analysis of beach marks indicates that the macrocracks observed on the fracture surface originate from the merging behavior of high-density microcrack clusters. The fatigue crack density at the rib-to-deck weld is severely underestimated, and numerous cracks have merged before reaching observable dimensions. This research provides a theoretical basis for comprehensively assessing the fatigue performance of orthotropic steel decks.

焊接残余应力是导致正交各向异性钢甲板产生多重裂纹的关键因素。然而，焊接残余应力对焊接接头多裂纹演化特性的影响尚不清楚。提出了一种考虑焊接残余应力松弛的多裂纹扩展分析方法。随后，研究了焊接残余应力和多重裂纹效应对疲劳寿命的影响机理。最后，通过实验揭示了多裂纹的演化特性。结果表明，考虑焊接残余应力的疲劳寿命预测结果趋于保守，而考虑焊接残余应力松弛效应的疲劳寿命预测结果与实验结果更为吻合。焊接残余应力加速了多重裂纹合并行为的发生。随着裂纹深度的增加，残余应力对深度方向裂纹扩展的影响逐渐减小，而多裂纹的合并行为成为结构断裂的关键驱动力。滩痕反分析表明，在断口上观察到的宏观裂纹源于高密度微裂纹簇的合并行为。肋-甲板焊缝处的疲劳裂纹密度被严重低估，许多裂纹在达到可观察的尺寸之前就合并了。该研究为全面评价正交异性钢甲板的疲劳性能提供了理论依据。

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引用次数: 0

Mode II strength of co-bonded adhesive joints at different strain rates 不同应变速率下共粘结接头的II型强度

IF 5.3 2区工程技术 Q1 MECHANICS

Engineering Fracture Mechanics

Pub Date : 2026-01-29 DOI: 10.1016/j.engfracmech.2026.111904

P. Villarroel , E.V. González , J.A. Artero-Guerrero , A. Cimadevilla , E. de Blanpre , V. Jacques

Bonded joints in composite structures are subjected to crash scenarios and their mechanical behaviour can depend on the strain rate. However, their dynamic characterization remains not fully standardized due to the difficulty of isolating the dynamic effects from the actual behaviour of the adhesive. The present study addresses this issue by developing, via finite element (FE) simulations, a slotted single-lap shear (SLS) specimen with a new set of dimensions tailored for pure mode II testing of co-bonded adhesive joints under quasi-static (QS) and dynamic conditions. This geometry is consistent with the manufacturing constraints of the Carbon-Fibre Reinforced Polymer (CFRP) adherents. The main novelty is the design of a custom metallic tooling to enhance dynamic equilibrium, reduce bending, and improve repeatability. Using Split Hopkinson Pressure Bar (SHPB) testing combined with Digital Image Correlation (DIC), results show that dynamic shear strength increases relative to the QS reference, but decreases at higher strain rates. The optimized set-up provides reliable data to support advanced modelling of composite structures under dynamic loading.

复合材料结构中的粘结接头受到碰撞的影响，其力学行为可能取决于应变速率。然而，由于很难从粘合剂的实际行为中分离出动态影响，它们的动态表征仍然没有完全标准化。本研究通过有限元（FE）模拟，开发了一种具有新尺寸的开槽单搭剪（SLS）试件，用于准静态（QS）和动态条件下共粘结接头的纯模式II测试，从而解决了这一问题。这种几何形状符合碳纤维增强聚合物（CFRP）附着物的制造限制。主要的新颖之处在于定制金属工具的设计，以增强动态平衡，减少弯曲，并提高可重复性。采用分离式霍普金森压杆（SHPB）与数字图像相关（DIC）相结合的试验结果表明，动态抗剪强度相对于QS参考值有所增加，但在应变速率较高时有所下降。优化后的设置为复合材料结构在动力荷载作用下的高级建模提供了可靠的数据支持。

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引用次数: 0

On the role of damage driving forces in scalar damage models for dynamic crack growth in 2D and 3D media 二维和三维介质中动态裂纹扩展的标量损伤模型中损伤驱动力的作用

IF 5.3 2区工程技术 Q1 MECHANICS

Engineering Fracture Mechanics

Pub Date : 2026-01-28 DOI: 10.1016/j.engfracmech.2026.111900

Thu Hien Tran , Hung Thanh Tran , Tinh Quoc Bui

This paper introduces an efficient local damage framework for numerically analyzing time-dependent crack growth in brittle and quasi-brittle materials under dynamic loading. The core of the approach utilizes a classical scalar damage model with an explicit dynamic solver and an energy-based regularization technique to circumvent mesh dependency while avoiding high computational costs. In fact, using the explicit solver for isotropic damage theory requires no system of equations to be solved; all calculations are performed through straightforward updates of the kinematic fields, history variables, and local damage variables, without any matrix inversion. We compare the performance of four different equivalent strain measures including the smooth Rankine, modified von Mises, enhanced bi-energy norm, and Mazars to identify the most suitable models for predicting dynamic fracture phenomena like mixed-mode shearing, crack branching, and fragmentation in two-dimensional and three-dimensional solids. The results show that the smooth Rankine norm demonstrates the best compatibility across challenging fracture problems. The modified von Mises and enhanced bi-energy norms also perform well when properly parameterized. In contrast, the Mazars strain norm shows notable limitations.

本文介绍了一种有效的局部损伤框架，用于动态加载下脆性和准脆性材料随时间裂纹扩展的数值分析。该方法的核心是利用经典的带有显式动态求解器的标量损伤模型和基于能量的正则化技术来避免网格依赖，同时避免高计算成本。事实上，使用各向同性损伤理论的显式求解器不需要求解方程组；所有的计算都是通过直接更新运动学场、历史变量和局部损伤变量来完成的，不需要任何矩阵反演。我们比较了光滑Rankine、改进von Mises、增强双能范数和Mazars四种不同等效应变测量的性能，以确定最适合预测二维和三维固体中混合模式剪切、裂纹分支和破碎等动态断裂现象的模型。结果表明，光滑朗肯范数在具有挑战性的断裂问题中表现出最佳的相容性。修正的von Mises规范和增强的双能规范在适当参数化时也表现良好。相比之下，Mazars应变规范显示出明显的局限性。

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引用次数: 0

Mode I/II-combined fracture condition of western hemlock characterized using an asymmetrical four-point fracture test of a side-grooved sample 通过侧槽试样的不对称四点断裂试验，表征了铁杉I/ ii型复合断裂状态

IF 5.3 2区工程技术 Q1 MECHANICS

Engineering Fracture Mechanics

Pub Date : 2026-01-27 DOI: 10.1016/j.engfracmech.2026.111899

Hiroshi Yoshihara, Makoto Maruta

Mode I/II combined fracture behavior of western hemlock was characterized using asymmetrical four-point fracture (AFPF) tests on side-grooved samples. The Mode I/II combination ratios were controlled by horizontally shifting the crack location in the sample, and the Mode I/II initiation stress intensity factors (SIFs) were determined under various combination ratios. In addition, mixed-mode bending (MMB) tests were conducted to validate the AFPF results. The relationships between the Mode I and Mode II critical SIFs characterized from both the AFPF and MMB tests could be approximated into elliptical functions, indicating that the AFPF test is effective for obtaining initiation SIFs under Mode I/II combined fracture conditions. When the characterization is limited to initiation SIFs, the AFPF test is more advantageous than the MMB test because the Mode I/II combination ratios can be varied more easily without large-scale equipment inevitably required for the MMB testing.

采用不对称四点断裂（AFPF）试验对铁杉的I/II型复合断裂行为进行了表征。通过水平移动试样中的裂纹位置来控制I/II型组合比，并确定不同组合比下的I/II型起始应力强度因子（SIFs）。此外，还进行了混模弯曲（MMB）试验来验证AFPF的结果。从AFPF和MMB试验中得到的I型和II型临界SIFs之间的关系可以近似为椭圆函数，表明AFPF试验对于获得I/II型复合断裂条件下的起始SIFs是有效的。当表征仅限于起始SIFs时，AFPF测试比MMB测试更有利，因为模式I/II组合比可以更容易地改变，而无需MMB测试不可避免地需要大型设备。

引用次数: 0

A 3D brittle fracture model with effect of microstructure, strain gradient and strain rate 考虑微观结构、应变梯度和应变速率影响的三维脆性断裂模型

IF 5.3 2区工程技术 Q1 MECHANICS

Engineering Fracture Mechanics

Pub Date : 2026-01-27 DOI: 10.1016/j.engfracmech.2026.111867

Yipeng Rao , Quanzhang Li , Zhiqiang Yang , Meizhen Xiang

Based on the two-scale asymptotic expansion theory, we establish a dynamic fracture model for 3D micro-cracked materials which extends the previous 2D results presented by the authors in Rao (2022); Rao et al. (2023). Using the two-scale theory for 3D problems, an analytical formulation of dynamic energy release rate is obtained that includes additive contributions of macroscopic strain, strain gradient and strain rate. The coefficients of the strain, strain gradient and strain rate are related to the microstructural size and derivatives of the homogenized (effective) elastodynamics moduli, which are determined by solutions of elementary elastodynamics problems defined in a reference unit cell. The microdamage evolution equation is developed by combining the analytical formulation of dynamic energy release rate with the Griffith fracture law. In contrast to the two-dimensional case where the normalized microcrack length is used as the measure of microdamage, in the three-dimensional case, the normalized microcrack area is used as the measure of microdamage, and then, the dynamic evolution equation of the microdamage variable for 3D problems has the same form as that for 2D cases. We analyze the properties of the homogenized elastodynamics moduli and compare them with those in the 2D cases. The coupling of microstructure size, strain gradient and strain rate are analyzed by examining local material responses and spallation experiment. The finite element simulations based on the model are well validated against available experimental results and previous reports.

基于双尺度渐近展开理论，我们建立了三维微裂纹材料的动态断裂模型，该模型扩展了Rao（2022）作者先前提出的二维结果；Rao等人（2023）。利用三维问题的双尺度理论，得到了包含宏观应变、应变梯度和应变速率加性贡献的动态能量释放率解析表达式。应变系数、应变梯度系数和应变速率系数与微观结构尺寸和均质（有效）弹性动力学模量的导数有关，它们由参考单元胞中定义的初等弹性动力学问题的解决定。将动态能量释放率解析公式与Griffith断裂定律相结合，建立了微损伤演化方程。在二维情况下，采用归一化微裂纹长度作为微损伤的度量，而在三维情况下，采用归一化微裂纹面积作为微损伤的度量，则三维问题的微损伤变量的动态演化方程与二维情况相同。我们分析了均匀化弹性动力学模量的性质，并与二维情况下的模量进行了比较。通过局部材料响应和剥落实验，分析了微观结构尺寸、应变梯度和应变速率的耦合关系。基于该模型的有限元模拟结果与已有的实验结果和前人的报道相比较，得到了很好的验证。

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引用次数: 0

Multiscale analysis of the entire fracture process of cemented granular materials Considering structural differences in the interlayer interfaces 考虑层间界面结构差异的胶结颗粒材料断裂全过程多尺度分析

IF 5.3 2区工程技术 Q1 MECHANICS

Engineering Fracture Mechanics

Pub Date : 2026-01-27 DOI: 10.1016/j.engfracmech.2026.111879

Yanan Zhang , Xin Cai , Xudong Chen , Xingwen Guo

To investigate the effect of different interlayer interface structures on the fracture behavior of Cemented granular materials (CGM) this study prepared three types of interlayer interface specimens untreated mortar and neat paste and conducted three-point bending fracture tests acoustic emission (AE) technology and 3D scanning technology to systematically analyze the entire fracture process of the interlayer interface in CGM. The results indicate that interlayer interface treatment significantly alters the fracture behavior of cemented granular materials with untreated interfaces exhibiting brittle failure while cement mortar and neat paste treatments enhance the bond strength and overall toughness of the interface delaying crack propagation and improving crack resistance. The neat paste-treated interface exhibits a lower initial

b

-value, a steady increase in the

b

-value, and a trend dominated by low-frequency main frequencies, indicating more coordinated microcrack propagation and a more stable interface structure. RA–AF parameters and Gaussian Mixture Model (GMM) clustering analysis show that, after neat paste and mortar treatments, the proportions of tensile cracks are 25.1% and 17.7%, respectively, and the consistency of crack propagation is enhanced. 3D scanning results show that the treated interface has more uniform bond strength and smoother crack propagation especially neat paste treatment effectively suppresses brittle fracture and improves fracture resistance This study provides theoretical support for optimizing interlayer interface treatment in cemented granular material dams and reveals the critical role of interface structure in the fracture process of cemented granular materials.

为了研究不同层间界面结构对胶结颗粒材料（CGM）断裂行为的影响，本研究制备了三种类型的层间界面试样，分别为未经处理的砂浆和整齐的膏体，并进行三点弯曲断裂试验、声发射（AE）技术和三维扫描技术，系统分析了CGM层间界面的整个断裂过程。结果表明：层间界面处理显著改变了未处理界面的胶结颗粒材料的断裂行为，界面表现为脆性破坏，而水泥砂浆和整齐浆处理提高了界面的粘结强度和整体韧性，延缓了裂缝扩展，提高了抗裂能力。整齐膏体处理界面的初始b值较低，b值逐渐增大，且主频率以低频为主，表明微裂纹扩展更加协调，界面结构更加稳定。RA-AF参数和高斯混合模型（GMM）聚类分析表明，经过纯浆和砂浆处理后，拉伸裂纹比例分别为25.1%和17.7%，裂纹扩展的一致性增强。三维扫描结果表明，处理后的界面具有更均匀的粘结强度和更平滑的裂纹扩展，特别是整齐膏体处理有效地抑制了脆性断裂，提高了抗断裂能力。本研究为优化胶结颗粒材料坝层间界面处理提供了理论支持，揭示了界面结构在胶结颗粒材料断裂过程中的关键作用。

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引用次数: 0

On the roles of welding residual stresses in determination of fracture toughness in austenitic stainless steel SUS 304 pipeline girth welds 焊接残余应力在测定奥氏体不锈钢sus304管道环焊缝断裂韧性中的作用

IF 5.3 2区工程技术 Q1 MECHANICS

Engineering Fracture Mechanics

Pub Date : 2026-01-25 DOI: 10.1016/j.engfracmech.2026.111871

Hui Huang , Yanli Wang , Jian Chen , Yongbing Li , Zhili Feng

Welding residual stresses especially the high tensile stresses are proved to have negative impacts on the fatigue and fracture behaviors of welded structures. In this study, a virtual fabrication of test specimens from welding process to specimen preparation was carried out by numerical simulation. An austenitic stainless steel multi-pass pipe welding was simulated by transient thermal–mechanical finite element analysis, the residual stresses were then mapped into the test specimen to evaluate fracture toughness. The findings in this study confirmed that, residual stress can be high in a sub-sized compact tensile specimen, which may accelerate or hinder the crack propagation during actual fatigue and fracture tests as reported in recent years. The influence of the cutting location and orientation of the specimen on fracture performance was investigated systematically to provide a fundamental understanding of welding residual stress and necessary insights into the specimen preparation procedure. Considering the limitation of measuring techniques and the complexity of the stress distribution, the developed numerical model can be a very useful tool to elucidate the stress evolution and quantify the effect of remaining welding stress on fracture toughness.

焊接残余应力特别是高拉应力对焊接结构的疲劳和断裂行为有负面影响。本文采用数值模拟的方法对试件进行了从焊接过程到试样制备的虚拟制作。采用瞬态热-力学有限元方法模拟了奥氏体不锈钢多道次管道焊接过程，并将残余应力映射到试样中，评估了试样的断裂韧性。本研究结果证实了近年来报道的在实际疲劳和断裂试验中，亚尺寸致密拉伸试样的残余应力可能很高，这可能加速或阻碍裂纹扩展。系统地研究了试样切割位置和方向对断裂性能的影响，以提供对焊接残余应力的基本理解和对试样制备过程的必要见解。考虑到测量技术的局限性和应力分布的复杂性，所建立的数值模型可以很好地阐明应力演化过程，并量化焊接残余应力对断裂韧性的影响。

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引用次数: 0