Engineering Fracture Mechanics最新文献

{"title":"A comparison between FEM predictions and DIC results of crack tip displacement field in AA2024-T3 CT specimens","authors":"E.R. Sérgio ,&nbsp;G.L. Gómez Gonzáles ,&nbsp;J.M. Vasco-Olmo ,&nbsp;F.V. Antunes ,&nbsp;P. Prates ,&nbsp;F.A. Díaz ,&nbsp;D.M. Neto","doi":"10.1016/j.engfracmech.2025.110964","DOIUrl":"10.1016/j.engfracmech.2025.110964","url":null,"abstract":"<div><div>In the current paper, fatigue crack growth is modelled using a node-release strategy based on crack tip plastic deformation. The accuracy of material elastic–plastic modeling is crucial for the quality of the numerical predictions. Stress–strain loops obtained in low cycle fatigue (LCF) were used to fit material constants for 2024-T3 aluminium alloy, which is the procedure usually followed. The material model was validated with Digital Image Correlation (DIC), with results obtained at different distances behind the crack tip in a thin CT specimen. Significant differences were found between FEM predictions and experimental results for plastic COD, which were attributed to an inadequate elastic–plastic model. In fact, the LCF tests always have small strain ranges, much smaller than the observed at the crack tip. The change of the isotropic hardening law from Swift to Voce improved the predicted plastic COD values. The final conclusion is that the fitting of the material parameters using LCF results must be validated with DIC-FEM comparisons for the case of thin specimens.</div></div>","PeriodicalId":11576,"journal":{"name":"Engineering Fracture Mechanics","volume":"318 ","pages":"Article 110964"},"PeriodicalIF":4.7,"publicationDate":"2025-02-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143464920","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}

{"title":"Machine learning approaches for predicting rock mode I fracture toughness: Insights from ISRM suggested CCNBD and SCB tests","authors":"Yuezong Yang ,&nbsp;Zhushan Shao ,&nbsp;Kui Wu ,&nbsp;Nannan Zhao ,&nbsp;Yujie Wang","doi":"10.1016/j.engfracmech.2025.110949","DOIUrl":"10.1016/j.engfracmech.2025.110949","url":null,"abstract":"<div><div>Mode I fracture represents a prevalent failure mechanism in rocks, attributed to the typically significantly lower tensile strength compared to their shear strength. The cracked chevron notched Brazilian disc (CCNBD) and semi-circular bend (SCB) tests are two techniques recommended by the International Society for Rock Mechanics (ISRM) for assessing mode I fracture toughness and are commonly employed in laboratory research. The fracture toughness of a rock specimen depends on its geometric dimensions and mechanical properties. Clarifying the geometric size impacts of various types of rocks in mode I fracture toughness testing is both costly and time-consuming. Machine learning offers a predictive approach for determining the fracture toughness of rocks. This investigation leverages six sophisticated machine learning models, encompassing decision regression tree (DRT), random regression forest (RRF), generalized regression neural network (GRNN), gaussian process regression (GPR), support vector machine (SVM) and generalized additive model (GAM), to forecast the mode I fracture toughness within the CCNBD and SCB testing paradigms. The variance in input variables between the two tests is attributed to the distinct geometrical attributes of the CCNBD and SCB specimens. Tensile strength, specimen radius, specimen thickness and three dimensionless parameters related to the initial and final cracked chevron notch lengths and specimen thickness are the input variables for CCNBD tests. Tensile strength, specimen radius, specimen thickness, notch length and the span of the two loading cylindrical rollers are input variables for SCB tests. Five evaluation indicators of machine learning models, i.e., mean absolute error, mean absolute percentage error, mean square error, root mean square error and coefficient of determination, are adopted to comprehensively evaluate the predictive performance of these models. According to the evaluative metrics, the DRT and GPR models emerge as the most effective for CCNBD and SCB tests, respectively. The significance of input variables for the prediction of mode I fracture toughness was delineated employing Shapley additive explanations. The findings underscore the paramount influence of tensile strength on mode I fracture toughness within both CCNBD and SCB testing methodologies. Considering the influences of sample value differences in CCNBD and SCB datasets and taking mean absolute percentage error and coefficient of determination as the evaluation indicators, the machine learning models are more suitable in predicting mode I fracture toughness in CCNBD tests than that in SCB tests. This study delivers valuable insights for the prediction of mode I fracture toughness in rocks via machine learning techniques.</div></div>","PeriodicalId":11576,"journal":{"name":"Engineering Fracture Mechanics","volume":"318 ","pages":"Article 110949"},"PeriodicalIF":4.7,"publicationDate":"2025-02-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143478608","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}

{"title":"Experimental study on mesoscopic fracture process and weakening mechanism of water on rockbursts","authors":"Jie Sun ,&nbsp;Kai Ling ,&nbsp;Shudong Zhang ,&nbsp;Dongqiao Liu","doi":"10.1016/j.engfracmech.2025.110950","DOIUrl":"10.1016/j.engfracmech.2025.110950","url":null,"abstract":"<div><div>Rockbursts induced by quasidynamic loads in deeply buried tunnels are highly susceptible to water and pose a critical engineering challenge. This study designs sandstone specimens with circular openings with various saturation levels to investigate the effects of water on rockbursts. Subsequently, rockbursts are triggered by quasi-dynamic loads in the true-triaxial loading state. The rockburst fracture process under different saturation levels and the fracture mode of the sidewall of the circular opening are analyzed using a microporous photography system and an acoustic emission (AE) monitoring system. The results indicate that water has a vital effect on the rockburst behavior of sandstone. Water had a dual effect on the fracture process of the sidewall during rockbursts, revealing a promoting effect on the tensile fracture before rockburst at lower saturation levels; however, a driving effect for shear fractures was observed when the saturation level exceeded 50%. The dual mechanisms of the fluid wedge and lubrication effects are considered critical factors in transforming the sidewall fracture mechanism before the rockbursts occur. However, water accelerates the macroscopic damage before the rockburst, but weakens the overall strength of the rockburst. The calculation results based on the particle image velocimetry (PIV) method showed that when the saturation level increased from 0% to 100%, the rockburst intensity decreased from moderate to slight. Finally, two mechanisms are summarized to explain the weakening effect of water on the severity of rockbursts: (i) the weakening effect of water on the ultimate energy storage capacity of sandstone units, leading to a decrease in the dynamic behavior of the initial failure; (ii) the increasing effect of water on plastic deformation enhanced the sustained energy dissipation behavior of sandstone units rather than promoting energy accumulation. This effect led to a decrease in the residual excess energy of sandstone under dynamic loads.</div></div>","PeriodicalId":11576,"journal":{"name":"Engineering Fracture Mechanics","volume":"318 ","pages":"Article 110950"},"PeriodicalIF":4.7,"publicationDate":"2025-02-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143487447","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}

{"title":"Mixed-mode I/III fracture properties of high-temperature granite under liquid nitrogen impact using the ENDB method with acoustic emission technique","authors":"Yilei Yuan ,&nbsp;Chaolin Wang ,&nbsp;Yu Zhao ,&nbsp;Kun Zheng ,&nbsp;Mingxuan Shen","doi":"10.1016/j.engfracmech.2025.110969","DOIUrl":"10.1016/j.engfracmech.2025.110969","url":null,"abstract":"<div><div>For hot dry rock (HDR) reservoirs with random cracks, mixed-mode I/III fracture will be involved when liquid nitrogen fracturing is performed to exploit the stored geothermal energy. In this paper, research on mixed-mode I/III fracture properties of high-temperature granite under liquid nitrogen impact using acoustic emission (AE) and three-dimensional scanning techniques. The experimental results indicate that as the pretreatment temperature increases, the damage inside the granite becomes greater, and fracture toughness and fracture work gradually decrease under different loading modes. From 25 °C (untreated) to 600 °C, the mode-Ⅰ fracture toughness and fracture work exhibit the greatest decrease, with reductions of 68.2 % and 67.8 % respectively, showing a stronger thermal sensitivity. The P-wave velocity has a good linear relationship with fracture toughness and fracture work. The energy-based 3D mean strain energy density criterion (3D-MSED) provides a more accurate prediction of the crack resistance of granite under different pretreatment conditions. The classification results of AE dominant frequency based on threshold classification are consistent with the macroscopic fracture mechanism of edge notched disc bend (ENDB) granite. The higher the pretreatment temperature, the greater the discreteness of slope angle (<em>SA</em>), the larger the joint roughness coefficient (<em>JRC</em>) of the fracture surface, and the rougher the fracture surface becomes.</div></div>","PeriodicalId":11576,"journal":{"name":"Engineering Fracture Mechanics","volume":"319 ","pages":"Article 110969"},"PeriodicalIF":4.7,"publicationDate":"2025-02-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143551785","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}

{"title":"Numerical investigation of the evolution behaviors of multiple cracks in rocks subjected to tension using field-enriched finite element method","authors":"Xiaoping Zhou ,&nbsp;Zhiming Jia ,&nbsp;Yulin Zou ,&nbsp;Zheng Li","doi":"10.1016/j.engfracmech.2025.110965","DOIUrl":"10.1016/j.engfracmech.2025.110965","url":null,"abstract":"<div><div>The coalescence behaviors of multi-cracks and competitive crack propagation problem are always the challenging issues in the field of fracture mechanics due to its complexities. In this paper, the field-enriched finite element approach coupling with the predictor-and-corrector (PAC) algorithm is first proposed to numerically investigate the interaction mechanisms among multi-cracks containing shielding and amplification effects. Moreover, the coalescence behaviors of multi-cracks as well as competitive crack propagation problem are studied. In a benchmark example, the plate containing two offset cracks is illustrated to validate the precision and applicability of this proposed method. In addition, two examples involving a square plate containing symmetrically distributed and randomly distributed multi-cracks are also examined. The results demonstrate the exceptional performance of the proposed approach in modeling the propagation and coalescence behaviors of complex multi-cracks, as well as capturing the competing growth and interaction among multi-cracks.</div></div>","PeriodicalId":11576,"journal":{"name":"Engineering Fracture Mechanics","volume":"318 ","pages":"Article 110965"},"PeriodicalIF":4.7,"publicationDate":"2025-02-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143474249","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}

{"title":"An automatic procedure for calibrating the fracture parameters of fibre-reinforced concrete","authors":"F. Suárez,&nbsp;J. Donaire-Ávila,&nbsp;J.F. Aceituno","doi":"10.1016/j.engfracmech.2025.110919","DOIUrl":"10.1016/j.engfracmech.2025.110919","url":null,"abstract":"<div><div>In this work a calibration procedure to obtain the material parameters that characterise the fracture behaviour of fibre-reinforced concrete (FRC) is presented. This procedure uses a proposed trilinear softening diagram recently implemented in a smeared crack model of the free finite element code OOFEM that allows reproducing the fracture behaviour of FRC and takes advantage of the optimisation package of SciPy, with both pieces of software being open-source and of free access for anyone interested in this field. This work presents the calibration procedure, which uses the Nelder–Mead algorithm to adjust the numerical result with the experimental diagram and discusses some key aspects, such as the number of reference points used in the calibration process or the weighting factors used with them, including the possibility of making some reference points more relevant than others in the calibration process. The influence of the mesh size and the element type used in the FEM model is also analysed. To evaluate the quality of the numerical approximation, a deviation factor is defined, which provides an scalar value that becomes lower as the numerical adjustment is closer to the experimental diagram in the reference points. The proposed procedure allows calibrating six parameters automatically with a meaningful time reduction and good accuracy. Using a higher number of reference points may lead to a better adjustment, although this study suggests that a good selection of the reference points is more effective than using a high number of reference points or using weighting factors to make some points more relevant than others. This procedure is finally validated by applying it with experimental results obtained with other types of FRC materials (different fibres and different fibre proportions) and specimen geometries.</div></div>","PeriodicalId":11576,"journal":{"name":"Engineering Fracture Mechanics","volume":"318 ","pages":"Article 110919"},"PeriodicalIF":4.7,"publicationDate":"2025-02-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143464987","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}

{"title":"Analysis of strain rate effect on fatigue crack of fixed frog nose rail","authors":"Jian Yang ,&nbsp;Mingjing Yue ,&nbsp;Taoshuo Bai ,&nbsp;Hui Zhu ,&nbsp;Jingmang Xu ,&nbsp;Kai Wang ,&nbsp;Yao Qian ,&nbsp;Ping Wang","doi":"10.1016/j.engfracmech.2025.110971","DOIUrl":"10.1016/j.engfracmech.2025.110971","url":null,"abstract":"<div><div>As a wheel traverses a fixed frog, it creates significant wheel-rail interaction, potentially causing fatigue cracks. The frog’s mechanical properties vary under wheel impact, making it crucial to consider the strain rate effect on frog materials when studying rolling contact fatigue. This study employs an explicit finite element method to develop a 3D transient rolling contact model of the wheel-frog system. The model captures the stress–strain state as the wheel traverses the frog. Quasi-static and impact compression tests are conducted on the nose rail material, and a dynamic constitutive model is established using the Johnson-Cook model. The J-S multiaxial fatigue damage prediction model is used to analyze the initiation location and angle of fatigue cracks in key cross-sections of the nose rail. The findings indicate that: The strain rate of the nose rail increases sharply under wheel impact but decreases to match that of the wing rail once the wheel load transition is complete; The U26Mn2Si2CrNiMo nose rail material shows significant strain rate effects, with yield strength increasing with strain rate, and the Johnson-Cook model effectively describes these effects; The strain rate effect significantly impacts effective stress and plastic strain, with maximum effective stress increasing and maximum plastic strain decreasing in areas with higher strain rates; While strain rate effects minimally impact the initiation location and angle of fatigue cracks in the longitudinal direction of the nose rail, they do influence the angle of sub-surface crack initiation in the rail. These results provide realistic and reliable strain rate-related mechanical parameters for simulating the dynamic contact behavior of the fixed frogs and offer guidance for their maintenance and repair.</div></div>","PeriodicalId":11576,"journal":{"name":"Engineering Fracture Mechanics","volume":"318 ","pages":"Article 110971"},"PeriodicalIF":4.7,"publicationDate":"2025-02-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143509606","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}

{"title":"Uncovering the damage behavior of heterogeneous grains in Mg-RE alloys","authors":"Hui Su ,&nbsp;Junsheng Wang ,&nbsp;Chen Liu ,&nbsp;Chengming Yan ,&nbsp;Chengpeng Xue ,&nbsp;Guangyuan Tian ,&nbsp;Zhihao Yang ,&nbsp;Xinghai Yang ,&nbsp;Quan Li ,&nbsp;Xingxing Li ,&nbsp;Yisheng Miao ,&nbsp;Shuo Wang","doi":"10.1016/j.engfracmech.2025.110967","DOIUrl":"10.1016/j.engfracmech.2025.110967","url":null,"abstract":"<div><div>Grain boundaries are often prone to damage due to local stress concentration and strain accumulations. However, the influence of heterogenous grain characteristics on damage behavior is not only a function of grain size, but also its orientations. In this study, a Crystal Plasticity Fast Fourier Transform (CPFFT) model has been coupled with phase field to simulate this heterogeneous grain effects on damage behavior. Using the heterogeneous grains from Electron Back Scatter Diffraction (EBSD) measurements of Mg-2Y and Mg-2Gd alloys, the damage propagation subjected to uniaxial tension has been simulated and it was found that grain size, Schmid factor, grain boundary misorientation angle, and geometric compatibility factor collectively influence the crack initiation and propagation. The inhomogeneous plastic deformation within the polycrystals, consequently manifesting diverse behaviors of damage evolution. Therefore, it is the coordination of heterogeneous crystal orientation and grain size which inhibits the initiation and propagation of cracks, thereby retarding the plastic instability and improving the material ductility.</div></div>","PeriodicalId":11576,"journal":{"name":"Engineering Fracture Mechanics","volume":"318 ","pages":"Article 110967"},"PeriodicalIF":4.7,"publicationDate":"2025-02-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143474248","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}

{"title":"Modeling the flexural behavior of concrete sections with longitudinal reinforcement and steel fibers using Fracture Mechanics concepts","authors":"Ángel De La Rosa ,&nbsp;Gonzalo Ruiz ,&nbsp;Jacinto R. Carmona","doi":"10.1016/j.engfracmech.2025.110918","DOIUrl":"10.1016/j.engfracmech.2025.110918","url":null,"abstract":"<div><div>This study introduces an analytical model for assessing the flexural strength of concrete sections reinforced with both longitudinal bars and steel fibers, grounded in Fracture Mechanics principles. By combining the compressive behavior model from Eurocode 2 with the tensile softening model from Model Code 2010, the proposed approach enables precise simulations of the compressive and tensile responses in reinforced concrete. The model characterizes the compression zone with a parabolic-linear stress–strain relationship and applies a linear softening law in the tensile zone under the flat crack hypothesis. This framework ensures compatibility between crack openings and reinforcement elongation, facilitating accurate calculations of stress distribution and fracture depth. The model’s results align reasonably well with experimental data from the scientific literature. It highlights significant size effects related to the brittleness number, which accounts for element size, tensile softening, and residual flexural strength. As a practical tool for structural design, this model offers reliable predictions of flexural behavior for various reinforced concrete configurations.</div></div>","PeriodicalId":11576,"journal":{"name":"Engineering Fracture Mechanics","volume":"318 ","pages":"Article 110918"},"PeriodicalIF":4.7,"publicationDate":"2025-02-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143452900","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}

{"title":"A novel water-loaded rig for characterising the cracking behavior of ceramic materials in future fusion reactor windows","authors":"Shan Tan-Ya ,&nbsp;Aurélien Gabieli ,&nbsp;Andrius Aleksa ,&nbsp;Sarha Florentine-Legry ,&nbsp;Sophie Steinlin ,&nbsp;Vincent Long ,&nbsp;Laurent Sabatier ,&nbsp;Stéphane Bourgeois ,&nbsp;Kyriakos Magdalis ,&nbsp;Gilles Bignan ,&nbsp;Christian Colin ,&nbsp;Chris Hardie","doi":"10.1016/j.engfracmech.2025.110923","DOIUrl":"10.1016/j.engfracmech.2025.110923","url":null,"abstract":"<div><div>Subcritical crack growth in tokamak vacuum vessel windows has been identified as a risk for magnetic confinement fusion reactors of the future. A first-of-its-kind water-loaded bend-test rig was designed and built to characterise this effect for representative window materials in non-irradiated conditions, at room temperature. This rig was built mostly from off-the-shelf components. Its loading rate can be easily adjusted via a pump. 38 specimens of fused silica were tested to failure at 2 loading rates. When fitted to a Weibull distribution, the characteristic strength was 112 MPa for a loading rate of 0.009 MPa/s, and 33 MPa for a loading rate of 0.066 MPa/s, corresponding to an observed increase in strength of 9% for an increase in loading rate by a factor of 6.3. Fitting a regression line to the data collected over this limited stressing range gives the subcritical crack growth parameters <span><math><mrow><mi>n</mi><mo>=</mo><mn>17</mn></mrow></math></span> and <span><math><mrow><mi>log</mi><mrow><mfenced><mrow><mi>B</mi><msup><mrow><msub><mi>σ</mi><mi>c</mi></msub></mrow><mrow><mi>n</mi><mo>-</mo><mn>2</mn></mrow></msup></mrow></mfenced></mrow><mo>=</mo><mn>38.4</mn></mrow></math></span>, which are comparable to values from literature for room-temperature alumina. This is the first experimental indication of possible subcritical crack growth in fused silica that has been observed and quantified. The impact of measurement uncertainty from this rig (±3.9%) on the quality of the Weibull distribution fit was quantified with a simulated noisy database and found to be negligible. Fractographic analysis of broken fragments also validated the experimental method. The results from this testing series will justify and inform future designs of subcritical crack growth tests for ceramics in irradiated conditions.</div></div>","PeriodicalId":11576,"journal":{"name":"Engineering Fracture Mechanics","volume":"318 ","pages":"Article 110923"},"PeriodicalIF":4.7,"publicationDate":"2025-02-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143510637","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}