{"title":"Numerical simulation of frost heaving deformation of fractured rocks considering heat-force coupling","authors":"Fengqi Shen , Wenliang Qiu , Haowei Zhu , Tianyu Wu , Lin Qi , Mingming Xing","doi":"10.1016/j.tafmec.2025.104921","DOIUrl":"10.1016/j.tafmec.2025.104921","url":null,"abstract":"<div><div>Rock engineering in cold regions faces significant challenges due to frost heave deformation in fractured rocks caused by freeze–thaw cycles. There is a lack of methods for modelling frost heaving deformation in fractured rocks. This study proposes a thermo-mechanical coupling model and a numerical simulation method to predict frost heave deformation in fractured rocks. In order to validate the new model and the numerical method, three typical factors affecting the freezing deformation of rocks, which are fracture size, number of fractures and fracture inclination, are considered. The frost heaving deformation of rocks under different fracture conditions is measured by designing and producing a testing device for the frost heaving deformation of fractured rocks. A three-dimensional numerical simulation model of frost heaving in fractured rock is established, and the correctness of the method is verified based on experimental results. The effects of fracture size, fracture number and fracture dip angle on the rock are analyzed, and the validity of the method is verified in two aspects: the overall longitudinal deformation of the rock and the frost heaving pressure. Further, the feasibility of applying the method to the fracture extension is tested. This work provides a reliable tool for assessing frost-related risks in geotechnical engineering, offering critical insights for disaster prevention in cold regions.</div></div>","PeriodicalId":22879,"journal":{"name":"Theoretical and Applied Fracture Mechanics","volume":"138 ","pages":"Article 104921"},"PeriodicalIF":5.0,"publicationDate":"2025-03-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143685371","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":"Investigation of mode I fracture resistance of hot mix asphalt using three testing protocols under the low temperature","authors":"Weimin Song, Wenlong Yan, Hao Wu, Zhicai Cui","doi":"10.1016/j.tafmec.2025.104937","DOIUrl":"10.1016/j.tafmec.2025.104937","url":null,"abstract":"<div><div>A variety of testing methodologies are currently employed to assess the fracture behaviors of asphalt mixtures. However, there is a notable variability in fracture parameters, such as the stress intensity factor (SIF) and fracture energy, when derived from different testing approaches. This study investigated the variations in fracture parameters, including the SIF, fracture energy, tensile stiffness index (TSI), and modified tensile stiffness index (MTSI), obtained from three distinct testing methods: the semi-circular bending (SCB) test, the three-point bending (TPB) test, and the semi-circular tension (SCT) test, all conducted under low-temperature conditions. The maximum tangential strain (MTS) criterion was utilized to elucidate the origins of the observed differences among the various fracture assessment methods. Results revealed that the load–displacement curves from the SCB and TPB tests were similar, characterized by a linear escalation in load up to the peak point, followed by a precipitous decline with minimal deformation post-peak load. In contrast, the SCT test exhibited a divergent behavior, with a gradual decrease in load post-peak and noticeable displacements. The TPB tests generated the highest fracture parameters in terms of SIF, fracture energy, and TSI. The SCB tests provided superior results for the SIF and fracture energy compared to the SCT tests. The AC10 mixture demonstrated enhanced fracture resistance relative to the AC16 mixture across all these parameters, which was mainly ascribed to the lower porosity of AC10. The introduction of a modified tensile stiffness index (MTSI) resulted in a lower coefficient of variance (COV) when compared to the traditional TSI, indicating less dispersion was induced among different test methods. Upon employing the MTS criterion in the analysis of fracture, it is determined that the inherent stress intensity factors (<em>K</em><sub>IC</sub>) for both AC10 and AC16 asphalt mixtures exceeded the apparent stress intensity factors (<em>K</em><sub>If</sub>). Furthermore, the consideration of T-stress in the analysis effectively diminished the variability in <em>K</em><sub>If</sub> values observed across the different testing methodologies.</div></div>","PeriodicalId":22879,"journal":{"name":"Theoretical and Applied Fracture Mechanics","volume":"138 ","pages":"Article 104937"},"PeriodicalIF":5.0,"publicationDate":"2025-03-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143685380","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}
Wei Li , Xiaobo Cao , Liang Cai , Ibrahim Elbugdady , Yuzhe Jin , Chuanwen Sun
{"title":"Microstructure related mechanical response and fatigue crack growth behavior of polymer electrolyte membrane under in-situ loading","authors":"Wei Li , Xiaobo Cao , Liang Cai , Ibrahim Elbugdady , Yuzhe Jin , Chuanwen Sun","doi":"10.1016/j.tafmec.2025.104934","DOIUrl":"10.1016/j.tafmec.2025.104934","url":null,"abstract":"<div><div>Polymer electrolyte membrane (PEM) is a key component in fuel cells, however, its mechanical degradation behavior driven by fatigue is not yet well understood. Herein, combined with digital image correlation and microscopic observation, the multiscale mechanical response and crack growth behavior of PEM associated with microstructure were investigated using multiple in-situ tests including uniaxial tensile, stress relaxation and crack growth with different stress ratios. Results show that PEM clearly presents the rate dependence and anisotropy. Combined with the area statistics of hydrophobic main chains before and after tension, the plastic deformation mechanism associated with molecular chain rotation and unwinding was explained, and a modified multilayer viscoelastic-plastic constitutive model in consideration of the effects of plane stress, anisotropy and true stress was developed. Furthermore, based on the analysis of strain field at the near crack-tip, the size of cyclic plastic zone tends to increase with the increasing of crack length and stress ratio, but the effect of crack length on crack growth rate is more significant due to the larger stress concentration effect. Finally, the failure mechanism associated with ligament, tearing plane and resilient fatigue striation was elucidated.</div></div>","PeriodicalId":22879,"journal":{"name":"Theoretical and Applied Fracture Mechanics","volume":"138 ","pages":"Article 104934"},"PeriodicalIF":5.0,"publicationDate":"2025-03-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143685382","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}
M.R.M. Aliha , S.M.N. Ghoreishi , A. Tavana , M. Molayem , N. Choupani
{"title":"On determination of critical strain energy release rate for mode II failure of asphaltic composite mixtures using assymetric SCB configuration","authors":"M.R.M. Aliha , S.M.N. Ghoreishi , A. Tavana , M. Molayem , N. Choupani","doi":"10.1016/j.tafmec.2025.104936","DOIUrl":"10.1016/j.tafmec.2025.104936","url":null,"abstract":"<div><div>Understanding the crack resistance of hot mix asphalt (HMA) composites under dominantly in-plane shear (mode II) at intermediate temperatures is an important issue for design and life assessment of asphaltic pavements. While at low temperatures the critical value of stress intensity factor (e.g. <em>K</em><sub>IIc</sub>) is often used as the fracture resistance index for asphalt mixtures, the J-index is probably a more reliable fracture parameter for medium temperatures to capture the inelastic behavior of HMA mixture. Accordingly, the concept of J-integral has been adopted for determining <em>J</em><sub>Ic</sub> value of bituminous mixtures under mode I using semi-circular bend (SCB) test. In this paper, this concept is extended to propose an index (called <em>J</em><sub>IIc</sub>) for investigating mode II failure resistance of HMA mixtures. To do that the strain energy values are determined at pure mode II using the multiple asymmetric SCB (ASCB) samples with different crack lengths. Using this method the <em>J</em><sub>IIc</sub> value was determined at 25 °C for four HMA mixtures made of limestone aggrgate-60/70 bitumen (L60), limestone aggregate-85/100 bitumen (L85), siliceous aggregate-60/70 bitumen (S60) and siliceous aggregate-85/100 bitumen (S85). The corresponding values of <em>J</em><sub>IIc</sub> for the investigated asphaltic mixtures varied from 3.5 to 7 kJ/m<sup>2</sup> that were significantly higher than the <em>J</em><sub>Ic</sub> value of asphaltic mixtures. The <em>J</em><sub>IIc</sub> value obtained from the L60 mixture was greater than the other mixtures and the S85 mixture showed the lowest <em>J</em><sub>IIc</sub>. In addition, corresponding values of critical mode II stress intensity factor and mode II fracture energy were determined for each mixture and their relationships with the <em>J</em><sub>IIc</sub> were investigated. In general, there were no proportional and linear relations between <em>K</em><sub>IIf</sub>, <em>G</em><sub>IIf</sub> and <em>J</em><sub>IIc</sub> in the HMA mixtures.</div></div>","PeriodicalId":22879,"journal":{"name":"Theoretical and Applied Fracture Mechanics","volume":"138 ","pages":"Article 104936"},"PeriodicalIF":5.0,"publicationDate":"2025-03-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143685309","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 elastic foundation modeling approach to bi-material interface crack problems of finite bond length","authors":"Yuning Zhang , Pingsha Dong","doi":"10.1016/j.tafmec.2025.104933","DOIUrl":"10.1016/j.tafmec.2025.104933","url":null,"abstract":"<div><div>There have been some significant advances in direct joining of dissimilar materials over recent years for enabling multi-material lightweight structures. As such, both dissimilar material joint design and structural integrity evaluation call for engineering fracture mechanics solutions to bi-material interface crack problems involving finite bond line length. This paper presents a novel elastic foundation modeling approach to address a set of two-dimensional bi-material interface crack problems. The analytical formulation presented enables the extraction of important length-scale parameters for supporting quantitative joint sizing and interrelating the mixed-mode energy release rates to the classical mode-mixity defined by bi-material crack tip singularity fields. The modeling results can be directly used for analyzing some common test configurations, e.g., “lap-shear” (LS) and “coach-peel” (CP) widely used by industry for ensuring optimal bond line sizing for both satisfactory mechanical performance and easy dis-assembly. To demonstrate the practical implications of this research, a group of bi-material (aluminum to steel) lap-shear fracture tests are modeled through a linear superposition of the solutions of the elementary load cases.</div></div>","PeriodicalId":22879,"journal":{"name":"Theoretical and Applied Fracture Mechanics","volume":"138 ","pages":"Article 104933"},"PeriodicalIF":5.0,"publicationDate":"2025-03-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143685379","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}
Zhongwen Yue , Xu Wang , Xingyuan Zhou , Huang Wang , Shengnan Xu , Meng Ren , Linzhi Peng
{"title":"Study on the dynamic fracture law of layered materials under the explosive load of slotted charge","authors":"Zhongwen Yue , Xu Wang , Xingyuan Zhou , Huang Wang , Shengnan Xu , Meng Ren , Linzhi Peng","doi":"10.1016/j.tafmec.2025.104932","DOIUrl":"10.1016/j.tafmec.2025.104932","url":null,"abstract":"<div><div>Directional fracture blasting with slotted charge is one of the main rock breaking methods for excavating layered rock mass tunnels. This article uses dynamic photoelastic method combined with high-speed photography technology to visualize the process of explosive stress waves and explosive cracks passing through vertical layers of different strengths caused by the explosion of slotted charge. The dynamic fracture law of layered materials with different strength layers under slotted charge explosion loads was studied. The results indicate that the greater the strength of the bedding plane, the more significant the waveform changes of the explosive stress wave when transmitted through the bedding plane. When the strength of the bedding is relatively high, the crack velocity is less affected by the bedding. When the strength of the bedding is weak and there is a significant difference from the strength of the specimen material, the velocity of the crack after passing through the bedding will undergo severe oscillations. Before the main crack reaches the bedding plane and after passing through it, the fracture mode of the crack is mainly mode-I. During the process of the crack passing through the bedding plane, the dynamic crack transforms from the mode-I crack to the mixed mode crack. Under the premise of a certain crack velocity, bedding angle, and physical and mechanical parameters of the specimen, the propagation trajectory of the crack passing through the bedding is related to the difference in bedding strength and specimen strength.</div></div>","PeriodicalId":22879,"journal":{"name":"Theoretical and Applied Fracture Mechanics","volume":"138 ","pages":"Article 104932"},"PeriodicalIF":5.0,"publicationDate":"2025-03-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143642513","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}
Lei Sun, Chong Li, Yue Cao, Zhijun Xu, Lianhai Tai, Huan Xia, MengHu Sun, Menglong Zha, ShuaiShuai Jiang
{"title":"Experimental study on the evolution of rock fractures induced by rolled static cracking agents in steeply inclined hard faults","authors":"Lei Sun, Chong Li, Yue Cao, Zhijun Xu, Lianhai Tai, Huan Xia, MengHu Sun, Menglong Zha, ShuaiShuai Jiang","doi":"10.1016/j.tafmec.2025.104927","DOIUrl":"10.1016/j.tafmec.2025.104927","url":null,"abstract":"<div><div>The static blasting method is the preferred approach for addressing hard faults within an inclined working face. The presence of shear stress within the inclined rock layers can significantly affect the cracking efficiency of the Rolled Static Cracking Agent(RSCA). To study the rupture damage characteristics of rocks under the expansion of RSCA with different shear stress magnitudes, a novel Compression Shear Coupling Test system (CSCT) was employed. Fracture tests were conducted on RSCA specimens at six different inclination angles (0°, 5°, 10°, 15°, 20°, and 25°) under constant pressure. Acoustic emission monitoring and full-field strain measurement were employed to analyze the dynamic fracture process and damage characteristics of the specimens. The results indicate that an increase in inclination accelerates the crack initiation efficiency of RSCA, causing cracks to propagate at lower expansion pressures. The magnitude of the shear stress component significantly affects the fracturing characteristics of the specimens; as the inclination increases, the proportion of shear cracks in the specimens increases significantly. Additionally, the AE energy, fractal dimension, and surface density of cracks initially decrease and then increase. The distribution of surface strain concentration areas is closely related to the inclination angle, with shear stress causing the maximum tensile stress point to shift towards the shear direction of the specimen, forming strip-shaped damage zones. As a key factor affecting rock fracturing, the shear stress component alters the crack propagation pattern during RSCA fracturing. The research results provide data support and theoretical reference for field applications.</div></div>","PeriodicalId":22879,"journal":{"name":"Theoretical and Applied Fracture Mechanics","volume":"138 ","pages":"Article 104927"},"PeriodicalIF":5.0,"publicationDate":"2025-03-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143636855","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":"Effect of residual stress on sulfide stress cracking and fracture toughness in carbon steel: A phase-field modeling approach","authors":"Alok Negi , Imad Barsoum","doi":"10.1016/j.tafmec.2025.104911","DOIUrl":"10.1016/j.tafmec.2025.104911","url":null,"abstract":"<div><div>The susceptibility of OCTG-grade alloys to sulfide stress cracking (SSC) in hydrogen sulfide (H<span><math><msub><mrow></mrow><mrow><mn>2</mn></mrow></msub></math></span>S)-rich sour environments poses a unique challenge for downhole oil and gas exploration, particularly when considering the role of residual stresses. These stresses, inherent in materials from fabrication processes, can strongly influence their cracking resistance even in the absence of external loads. This study numerically examines the effect of residual stresses on the fracture toughness (<span><math><msub><mrow><mi>K</mi></mrow><mrow><mi>ISSC</mi></mrow></msub></math></span>) measurements associated with SSC resistance of a high-strength low-alloy carbon steel C110 in H<span><math><msub><mrow></mrow><mrow><mn>2</mn></mrow></msub></math></span>S-containing aqueous test solution using industry-standard single-edge notched tension (SENT) and double-cantilever beam (DCB) testing methodologies. Residual stresses are measured on pipe samples and are incorporated into the finite element model of the pipe through a thermo-mechanical equivalent loading. The residual stress field is then mapped onto the fracture mechanics test specimens to represent the initial stress distributions. A coupled deformation-diffusion phase-field framework is implemented in COMSOL to simulate crack propagation under the combined influence of residual stress and environmental factors. The results offer insights into SSC mechanisms, demonstrating that elevated residual stress levels in both SENT and DCB tests affect SSC initiation thresholds and arrest, signifying reduced fracture toughness and increased susceptibility to SSC. This study underscores the importance of considering residual stresses in fracture-mechanics-based SSC integrity assessments to improve the reliability of components in sour service applications.</div></div>","PeriodicalId":22879,"journal":{"name":"Theoretical and Applied Fracture Mechanics","volume":"138 ","pages":"Article 104911"},"PeriodicalIF":5.0,"publicationDate":"2025-03-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143644928","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":"Mechanical behavior and damage constitutive model of fractured granite after high-temperature treatment based on 3D digital image correlation","authors":"Lan Zeng , Jialong Zhang , Shi Liu","doi":"10.1016/j.tafmec.2025.104919","DOIUrl":"10.1016/j.tafmec.2025.104919","url":null,"abstract":"<div><div>A high-temperature environment, cracks, and surface pressure of the rock affect the deep mining of rock masses and nuclear waste disposal. We used the Muskhelishvili theory of fracture mechanics to deduce the fracture stress intensity K of granite samples affected by compressive stress, fractures, and gas–vapor pressure. We established a high-temperature damage constitutive model based on the Burr distribution with an effective stress invariant and the Hoek-Brown (H-B) criterion. Uniaxial mechanical loading and axial compression tests were conducted on granite samples with prefabricated cracks after different high-temperature treatments. Three-dimensional digital image correlation (3D-DIC) was used to analyze the mechanical behavior and strain localization of the fractured rock samples affected by temperature and stress. The results showed that the elastic modulus reached the maximum at the largest inclination angle at different heat treatment temperatures. The surface principal strain increased uniformly before the stress–strain peak, strain localization increased, and the macroscopic cracks in the post-peak region expanded rapidly at different temperatures. The dominant failure mechanism of the granite samples was tensile shear failure at different temperatures and fracture angles. The strain data obtained by placing virtual extenders in different positions and directions on the rock surface are in good agreement with the experimental data. The predicted results of the high-temperature damage constitutive model aligned well with the experimental results, indicating the model accurately predicted the evolution of axial compression fracture of heat-damaged fractured rock. The results provide new insights into the instability mechanism of rock masses in different environments.</div></div>","PeriodicalId":22879,"journal":{"name":"Theoretical and Applied Fracture Mechanics","volume":"138 ","pages":"Article 104919"},"PeriodicalIF":5.0,"publicationDate":"2025-03-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143628547","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}
Xingyu Yang , Hao Liu , Yu Gong , Dingli Tian , Jianyu Zhang , Ning Hu
{"title":"Influence of structured surface on the interlaminar delamination properties of bonded fiber-metal laminates","authors":"Xingyu Yang , Hao Liu , Yu Gong , Dingli Tian , Jianyu Zhang , Ning Hu","doi":"10.1016/j.tafmec.2025.104930","DOIUrl":"10.1016/j.tafmec.2025.104930","url":null,"abstract":"<div><div>Fiber-metal laminates (FMLs) often exhibit weak interlayer mechanical properties. Delamination is a common issue across FMLs and significantly affects the overall mechanical performance, highlighting the critical need to enhance the interfacial bonding between metal and resin. Structured surface treatment has emerged as a promising method to improve interfacial bonding and has garnered significant attention in adhesive bonding applications. This study investigates the impact of surface structuring on delamination properties by designing two groove patterns (circular and hexagonal) on the metal surface of carbon fiber-reinforced aluminum alloy laminates (CARALL). Specimens were prepared and subsequently subjected to mode I and mode II static delamination tests. Test results indicate that both circular and hexagonal grooves substantially enhance interlaminar fracture toughness, with hexagonal grooves showing a superior improvement. Additionally, finite element models for double cantilever beam (DCB) and end-notched flexure (ENF) tests were developed using the cohesive zone model and progressive damage method. The numerical load–displacement curves were consistent with experimental curves, confirming the accuracy and applicability of the finite element approach.</div></div>","PeriodicalId":22879,"journal":{"name":"Theoretical and Applied Fracture Mechanics","volume":"138 ","pages":"Article 104930"},"PeriodicalIF":5.0,"publicationDate":"2025-03-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143685310","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}