Engineering Fracture Mechanics最新文献_第4页

Model for predicting type Ι fatigue crack growth rate in RKE field considering stress gradient 考虑应力梯度的 RKE 场中Ι型疲劳裂纹生长率预测模型

IF 4.7 2区工程技术

Engineering Fracture Mechanics Pub Date : 2024-10-19 DOI: 10.1016/j.engfracmech.2024.110579

{"title":"Model for predicting type Ι fatigue crack growth rate in RKE field considering stress gradient","authors":"","doi":"10.1016/j.engfracmech.2024.110579","DOIUrl":"10.1016/j.engfracmech.2024.110579","url":null,"abstract":"<div><div>Based on the stress–strain field at the crack tip of Rice-Kujawski-Ellyin (RKE) and considering the stress gradient effect near the crack tip of type I, a fatigue crack growth rate prediction model L-SG (RKE) for type I is proposed in this paper. Firstly, the stress gradient change value of 1 % at the crack tip is considered as the characteristic distance (stress gradient influence range), and the ratio of the equivalent stress to the far-field stress in the stress gradient influence range is defined as the stress gradient influence coefficient <em>ρ</em>; Secondly, the new model L-SG (RKE) is proposed to quantitatively describe the fatigue crack growth behavior by using the stress–strain field at the crack tip of RKE, and the stress gradient influence coefficient <em>ρ</em> is introduced, and then the crack tip passivation radius <em>r</em><sub>p</sub> is defined to eliminate the crack tip singularity, and the plastic strain energy failure criterion is combined.; Finally, the prediction effect of the L-SG (RKE) model is verified by 6 metal materials and the fatigue crack growth rate test results of 2 groups of 45 steel CT specimens, and compared with the SHI-CAI (RKE) model. At the same time, based on the <em>R</em><sup>2</sup> fitting effect and the different requirements of the three stages of fatigue crack propagation, the prediction effect of the two prediction models is analyzed, and comprehensive evaluation from two aspects of safety and accuracy. The results show that the L-SG (RKE) prediction model can better reflect the actual fatigue crack propagation behavior, and can meet the requirements of practical engineering for the accuracy and safety of the prediction model. Especially, the prediction results of physical cracks in 45 steel shaft parts by this model agrees well with the experimental data.</div></div>","PeriodicalId":11576,"journal":{"name":"Engineering Fracture Mechanics","volume":null,"pages":null},"PeriodicalIF":4.7,"publicationDate":"2024-10-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142529341","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

Acoustic Emission characteristics and damage evolution of Concrete-Encased CFST columns under compressive load 抗压荷载下混凝土嵌入式 CFST 柱的声发射特性和损伤演变

IF 4.7 2区工程技术

Engineering Fracture Mechanics Pub Date : 2024-10-19 DOI: 10.1016/j.engfracmech.2024.110578

{"title":"Acoustic Emission characteristics and damage evolution of Concrete-Encased CFST columns under compressive load","authors":"","doi":"10.1016/j.engfracmech.2024.110578","DOIUrl":"10.1016/j.engfracmech.2024.110578","url":null,"abstract":"<div><div>Concrete-Encased Concrete Filled Steel Tubular (CE-CFST) is usually served as a compression member in engineering structures due to its high performance. It is crucial to reveal its compressive failure mechanism and the damage evolution law. This study used Acoustic Emission (AE) technology to monitor the compressive failure behavior of seven groups of CE-CFST columns with different diameter-width ratio, slenderness ratio and eccentricity, and then the AE signal characteristics and structural damage evolution law were discussed. Results show that the curve of AE characteristics can be used for effectively identifying the damage stages of CE-CFST structures. The failure process can be divided into six stages: initial compaction, stable growth of micro cracks, unstable propagation of macro cracks, collapsing of the outer RC structure, bulging of the core CFST structure and overall failure. The AE characteristic parameters, RA-AF value and b value are closely related to stress and crack of structure, and can be used for early warning of structural failure during the stage of unstable crack propagation. Particularly, the failure of outer concrete can be judged as b value drops to the minimum. The current study is of great significance for understanding the damage evolution process and achieving damage assessment of CE-CFST structures.</div></div>","PeriodicalId":11576,"journal":{"name":"Engineering Fracture Mechanics","volume":null,"pages":null},"PeriodicalIF":4.7,"publicationDate":"2024-10-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142529416","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

Experimental study on fracture properties of heat-treated granite in I-II mixed mode suffered from water and liquid nitrogen cooling methods 水和液氮冷却方法导致 I-II 混合模式热处理花岗岩断裂特性的实验研究

IF 4.7 2区工程技术

Engineering Fracture Mechanics Pub Date : 2024-10-18 DOI: 10.1016/j.engfracmech.2024.110570

{"title":"Experimental study on fracture properties of heat-treated granite in I-II mixed mode suffered from water and liquid nitrogen cooling methods","authors":"","doi":"10.1016/j.engfracmech.2024.110570","DOIUrl":"10.1016/j.engfracmech.2024.110570","url":null,"abstract":"<div><div>Hot dry rock (HDR) development is significant for solving energy problems and realizing energy conservation and emission reduction. Liquid nitrogen (LN<sub>2</sub>) fracturing and hydraulic fracturing can form cracks in the HDR and improve the efficiency of geothermal energy mining. Therefore, it is necessary to study the fracture characteristics of high-temperature granite under different cooling methods. In this study, the deterioration of the physical and mechanical properties of granite subjected to high-temperature treatment under water cooling and LN<sub>2</sub> cooling was studied. Two I/II mixed modes (tensile orientation mode and shear orientation mode) and a pure II mode fracture characteristics of cracked straight-through Brazilian disc (CSTBD) specimens made of granite were explored. The displacement and strain fields of cracked granite specimens were measured by using a digital image correlation (DIC) method. The results show that when the temperature is 25℃, 200℃, and 400℃, the loading angle and cooling method have a great influence on the fracture mechanical characteristics of the granite. In general, the increase of loading angle and LN<sub>2</sub> cooling will lead to the decrease of peak load. For example, at 200℃, <em>β</em> = 15°, the deterioration degree of water-cooled and LN<sub>2</sub>-cooled specimens is 13.77 % and 16.69 %, respectively. When <em>β</em> = 23°, it increases to 14.62 % and 19.91 %, respectively. At the same time, an interesting phenomenon was found in the study. At 400℃, due to the Leidenfrost effect, the peak load of LN<sub>2</sub>-cooled specimens was higher than that of water-cooled specimens, and the further increase of temperature weakened the effect. When the temperature is 600℃, the difference between the loading angle and the cooling method is weakened.</div></div>","PeriodicalId":11576,"journal":{"name":"Engineering Fracture Mechanics","volume":null,"pages":null},"PeriodicalIF":4.7,"publicationDate":"2024-10-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142529343","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

The field-enriched finite element method with gravity effects for simulating the cracking behaviors of large-scale engineering rock masses 用于模拟大型工程岩体开裂行为的重力效应现场富集有限元法

IF 4.7 2区工程技术

Engineering Fracture Mechanics Pub Date : 2024-10-18 DOI: 10.1016/j.engfracmech.2024.110569

{"title":"The field-enriched finite element method with gravity effects for simulating the cracking behaviors of large-scale engineering rock masses","authors":"","doi":"10.1016/j.engfracmech.2024.110569","DOIUrl":"10.1016/j.engfracmech.2024.110569","url":null,"abstract":"<div><div>The field-enriched finite element method uses a scalar field defined as a field variable to describe cracks and characterize their impact on the displacement field and stress field of the solution model. It is capable of avoiding remeshing and employing level set functions to describe cracks when simulating the propagation of cracks. In this work, a field-enriched finite element model with gravity effects is proposed to simulate the large-scale failure process of engineering rock masses, and several numerical cases of geotechnical engineering are successfully analyzed. First, by introducing the unified tensile fracture criterion into the numerical model, the large-scale failure process of the intact slope is simulated. Second, the sliding process of rock slopes containing en echelon joints is numerically investigated. Third, the cracking process of the concrete dam is analyzed. Finally, the effects of joint and bedding plane inclination angles on the stability of tunnel chamber in transversely isotropic rock mass are studied. The numerical results indicate that the numerical method proposed in this work can accurately solve the large-scale failure process of rock masses.</div></div>","PeriodicalId":11576,"journal":{"name":"Engineering Fracture Mechanics","volume":null,"pages":null},"PeriodicalIF":4.7,"publicationDate":"2024-10-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142529342","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

Modelling of fracture-involved large strain behaviors of amorphous glassy polymers via a unified physically-based constitutive model coupled with phase field method 通过基于物理的统一构成模型和相场法模拟无定形玻璃态聚合物的断裂大应变行为

IF 4.7 2区工程技术

Engineering Fracture Mechanics Pub Date : 2024-10-18 DOI: 10.1016/j.engfracmech.2024.110546

{"title":"Modelling of fracture-involved large strain behaviors of amorphous glassy polymers via a unified physically-based constitutive model coupled with phase field method","authors":"","doi":"10.1016/j.engfracmech.2024.110546","DOIUrl":"10.1016/j.engfracmech.2024.110546","url":null,"abstract":"<div><div>To promote the application of amorphous glassy polymers in structural components, a reliable prediction of the deformation and the potential fracturing behaviors is in demand. This work aims to provide a simple and feasible computational method to analyze the large strain behaviors, including elasticity, viscoplasticity, and the subsequent fracture, of amorphous glassy polymers. This is achieved by incorporating a physically-based constitutive model coupled with the fracture phase field method into the commercial finite element software Abaqus/Explicit. Inside the constitutive model, shear-yielding, crazing, and disentangling are considered as the underlying mechanisms for viscoplastic deformation and damage initiation. It is noteworthy that a unified craze-initiation criterion with a clear physical meaning is proposed, distinguishing this work from the previous in the literature. Moreover, a relatively user-friendly numerical implementation is suggested by exploiting the built-in features of Abaqus/Explicit. Taking the typical amorphous glassy polymers for example, i.e., polycarbonate (PC) and poly-methyl-methacrylate (PMMA), various experiments from the literature have been simulated. The proposed approach has been validated, since an acceptable agreement between the simulated and experimental results is realized.</div></div>","PeriodicalId":11576,"journal":{"name":"Engineering Fracture Mechanics","volume":null,"pages":null},"PeriodicalIF":4.7,"publicationDate":"2024-10-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142529413","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

A novel experimental method for studying rock collision 研究岩石碰撞的新型实验方法

IF 4.7 2区工程技术

Engineering Fracture Mechanics Pub Date : 2024-10-17 DOI: 10.1016/j.engfracmech.2024.110542

{"title":"A novel experimental method for studying rock collision","authors":"","doi":"10.1016/j.engfracmech.2024.110542","DOIUrl":"10.1016/j.engfracmech.2024.110542","url":null,"abstract":"<div><div>This paper introduces a new experimental method for studying rock collision by making full use of the beauty of stress wave theory. In this method, a newly developed energy transmission component was placed between the gas gun and the transmitted bar of a split Hopkinson pressure bar (SHPB). The forementioned component consists of an incident bar which moves frictionlessly within a specified distance, a circular steel plate welded to the incident bar, and a support base which is bolted to the SHPB bed. A rock specimen is attached to the farther end of the incident bar. When the striker bar, propelled by the gas gun impacts the incident bar, a compressive stress wave is transmitted from the incident bar to the rock specimen. When the compressive wave arrives at the free end of the rock specimen, it is reflected into a tensile wave. Then when the pure stress becomes tensile and it is over the tensile strength of the glue at the interface between the rock specimen and the incident bar, the rock specimen is ejected, and then the ejected specimen will collide with the transmitted bar. During specimen flight, the velocity of the rock specimen can be measured by a laser instrument, while the remained energy transferred to the transmitted bar is measured by strain gauges attached to it. The process of rock specimen flight before collision and fragment flight after collision can be photographed using a high-speed camera. This experimental method can be used to not only study a collision between a moving rock and another object, but also imitate a drop weight test. By using this new method, seven rock collision tests were successfully conducted.</div></div>","PeriodicalId":11576,"journal":{"name":"Engineering Fracture Mechanics","volume":null,"pages":null},"PeriodicalIF":4.7,"publicationDate":"2024-10-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142446963","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Data-driven evaluation of the Paris’ law parameters in polyethylene pipe grades — Increasing the precision of fracture mechanical lifetime estimation 数据驱动的聚乙烯管材牌号巴黎定律参数评估 - 提高断裂机械寿命估算的精度

IF 4.7 2区工程技术

Engineering Fracture Mechanics Pub Date : 2024-10-16 DOI: 10.1016/j.engfracmech.2024.110540

{"title":"Data-driven evaluation of the Paris’ law parameters in polyethylene pipe grades — Increasing the precision of fracture mechanical lifetime estimation","authors":"","doi":"10.1016/j.engfracmech.2024.110540","DOIUrl":"10.1016/j.engfracmech.2024.110540","url":null,"abstract":"<div><div>The Paris’ Law parameters <span><math><mi>A</mi></math></span> and <span><math><mi>m</mi></math></span> are a necessity for predicting lifetimes of structural components under static or fatigue loading that fail due to crack initiation and propagation. Conventional methods require measurements of crack growth kinetics that involve direct or indirect monitoring of physical crack extension during long-term experiments. Usually, measurement series also involve multiple specimens in order to obtain a crack growth controlled failure diagram of an investigated material under relevant load conditions. In this contribution a combination of simple numerical, statistical and analytical approaches is presented to obtain <span><math><mi>A</mi></math></span> and <span><math><mi>m</mi></math></span> without the need to measure actual crack growth. This is accomplished by reformulating the Paris’ Law to express <span><math><mi>A</mi></math></span> as a function of <span><math><mi>m</mi></math></span>. The parameter <span><math><mi>m</mi></math></span> is varied within a reasonable range to generate an analytical function for <span><math><mi>A</mi></math></span> that solves the equation of the Paris’ Law based lifetime for a single specimen. A subsequent superposition of all available specimens reveals an intersection of all <span><math><mi>A</mi></math></span> functions at the technically relevant pair of <span><math><mi>A</mi></math></span> and <span><math><mi>m</mi></math></span> values that are capable of describing the lifetime of all specimens with a minimum error. The obtained best-fitting <span><math><mi>A</mi></math></span> and <span><math><mi>m</mi></math></span> are in good agreement with literature and are able to predict the lifetime of previously published sample data based upon cyclic Cracked Round Bar test results with an average error of 3.30 ± 2.67%.</div></div>","PeriodicalId":11576,"journal":{"name":"Engineering Fracture Mechanics","volume":null,"pages":null},"PeriodicalIF":4.7,"publicationDate":"2024-10-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142529425","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

An advanced fast multipole dual boundary element method for analyzing multiple cracks propagation 用于分析多裂纹扩展的先进快速多极双边界元方法

IF 4.7 2区工程技术

Engineering Fracture Mechanics Pub Date : 2024-10-16 DOI: 10.1016/j.engfracmech.2024.110547

引用次数: 0

Creep-to-rupture of T91 steel in static liquid lead-bismuth eutectic: Effects of cyclic temperature and oxygen environment 静态液态铅铋共晶中 T91 钢的蠕变到破裂：循环温度和氧气环境的影响

IF 4.7 2区工程技术

Engineering Fracture Mechanics Pub Date : 2024-10-16 DOI: 10.1016/j.engfracmech.2024.110539

引用次数: 0

A novel impact approach based on electromagnetic loading technology: A case study on CFRP/Al riveted structures 基于电磁加载技术的新型冲击方法：CFRP/Al 铆接结构案例研究

IF 4.7 2区工程技术

Engineering Fracture Mechanics Pub Date : 2024-10-16 DOI: 10.1016/j.engfracmech.2024.110555

{"title":"A novel impact approach based on electromagnetic loading technology: A case study on CFRP/Al riveted structures","authors":"","doi":"10.1016/j.engfracmech.2024.110555","DOIUrl":"10.1016/j.engfracmech.2024.110555","url":null,"abstract":"<div><div>To investigate the mechanical response and damage behavior of aircraft fuselage composite structures under out-of-plane impact loads more efficiently and flexibility, this paper proposed a novel impact approach and testing platform based on inductive coils to yield electromagnetic impact force. The influence of system key parameters on the electromagnetic loading waveforms were analyzed using an electromagnetic field finite element model. Single/repeated impact tests on CFRP/aluminium alloy (Al) riveted structures were conducted at different voltages (energies) based on this approach. The results indicate that the electromagnetic impact (EMI) approach exhibits significant advantages in both variable strain rate loading and continuous impact loading scenarios. This device can efficiently achieve multi-point and multiple impact loading. The electromagnetic impact forces with various amplitudes and pulse-widths can be accurately obtained by altering voltage and capacitance values, which can demonstrate the good experimental consistency of such test approach. Besides, with this test method, the load threshold for damage formation can be clearly defined: once the impact force exceeds the damage threshold load, the delamination area of the CFRP laminates expand as the impact energy increases. Note that when the provided out-of-plane impact load is slightly higher than the damage threshold load by changing the voltage, significant delamination damage may suddenly manifest in any one impact event of the repeated impacts.</div></div>","PeriodicalId":11576,"journal":{"name":"Engineering Fracture Mechanics","volume":null,"pages":null},"PeriodicalIF":4.7,"publicationDate":"2024-10-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142529422","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