Pub Date : 2024-04-20DOI: 10.1177/10567895241245754
Jinhui Guo, Yousong Xue, Bohong Gu, Baozhong Sun
Defect effects of carbon fiber composites under dynamic impact conditions are important to mechanical behavior design in the aerospace field. Here we report the defect effect on the impact compressive behavior of 3D braided composites at high strain rates from 550/s to 1240/s. The defect effect on damage behavior was observed by high-speed photography and digital image correlation (DIC) technology. A finite element analysis (FEA) model was developed to show the defect effect on stress distribution and thermo-mechanical behavior. The defect structure reduces the compressive strength of the composite and causes more brittle and catastrophic failure compared with the perfect composite. The defect effect on the compressive behaviors is more significant at higher strain rates. FEA results show that the defect structure causes local stress concentration, high adiabatic temperature rise, and high stress in the X-shaped shear band region, thereby accelerating composite failure.
碳纤维复合材料在动态冲击条件下的缺陷效应对航空航天领域的机械性能设计非常重要。在此，我们报告了缺陷对三维编织复合材料在 550/s 至 1240/s 高应变速率下冲击压缩行为的影响。通过高速摄影和数字图像相关（DIC）技术观察了缺陷对损伤行为的影响。建立的有限元分析（FEA）模型显示了缺陷对应力分布和热机械行为的影响。与完美的复合材料相比，缺陷结构降低了复合材料的抗压强度，导致更多的脆性和灾难性破坏。在应变速率较高时，缺陷对抗压行为的影响更为显著。有限元分析结果表明，缺陷结构会导致局部应力集中、绝热温升高以及 X 形剪切带区域的高应力，从而加速复合材料失效。
{"title":"Defect effect on high strain rate compressive behaviors of 3D braided composites","authors":"Jinhui Guo, Yousong Xue, Bohong Gu, Baozhong Sun","doi":"10.1177/10567895241245754","DOIUrl":"https://doi.org/10.1177/10567895241245754","url":null,"abstract":"Defect effects of carbon fiber composites under dynamic impact conditions are important to mechanical behavior design in the aerospace field. Here we report the defect effect on the impact compressive behavior of 3D braided composites at high strain rates from 550/s to 1240/s. The defect effect on damage behavior was observed by high-speed photography and digital image correlation (DIC) technology. A finite element analysis (FEA) model was developed to show the defect effect on stress distribution and thermo-mechanical behavior. The defect structure reduces the compressive strength of the composite and causes more brittle and catastrophic failure compared with the perfect composite. The defect effect on the compressive behaviors is more significant at higher strain rates. FEA results show that the defect structure causes local stress concentration, high adiabatic temperature rise, and high stress in the X-shaped shear band region, thereby accelerating composite failure.","PeriodicalId":13837,"journal":{"name":"International Journal of Damage Mechanics","volume":"1 1","pages":""},"PeriodicalIF":4.2,"publicationDate":"2024-04-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140622799","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}
Pub Date : 2024-04-19DOI: 10.1177/10567895241245501
George Z Voyiadjis, Peter I Kattan
This work focuses on the dissection of the damage variable within solid materials. The underlying assumption is that damage within a solid primarily stems from the presence of various defects. The conventional approach to breaking down the damage variable into two parts – one attributed to the first defect type and the other to the second defect type – is both explored and expanded in a coherent mathematical manner. Within this context, a novel and asymmetric dissection of the damage variable is formulated. This fresh asymmetrical approach presents an alternative to the traditional symmetric dissection of the damage variable. Initially, the dissection considerations are carried out in a one-dimensional context using scalar values. However, this methodology is subsequently generalized employing tensors. In the end, an illustrative example is demonstrated.
{"title":"A new unsymmetrical decomposition of the damage variable","authors":"George Z Voyiadjis, Peter I Kattan","doi":"10.1177/10567895241245501","DOIUrl":"https://doi.org/10.1177/10567895241245501","url":null,"abstract":"This work focuses on the dissection of the damage variable within solid materials. The underlying assumption is that damage within a solid primarily stems from the presence of various defects. The conventional approach to breaking down the damage variable into two parts – one attributed to the first defect type and the other to the second defect type – is both explored and expanded in a coherent mathematical manner. Within this context, a novel and asymmetric dissection of the damage variable is formulated. This fresh asymmetrical approach presents an alternative to the traditional symmetric dissection of the damage variable. Initially, the dissection considerations are carried out in a one-dimensional context using scalar values. However, this methodology is subsequently generalized employing tensors. In the end, an illustrative example is demonstrated.","PeriodicalId":13837,"journal":{"name":"International Journal of Damage Mechanics","volume":"50 1","pages":""},"PeriodicalIF":4.2,"publicationDate":"2024-04-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140621537","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}
Pub Date : 2024-04-12DOI: 10.1177/10567895241245753
Qi Xian-yin, Geng Dian-dong, Xu Ming-zhe, Ke Ting
To investigate the mechanical properties and damage evolution law of layered shale under varying moisture contents, we conducted triaxial compression experiments on rock samples with different bedding angles and moisture levels. This study analyzed the variations in mechanical properties of layered shale under different conditions, and established a predicted model for elastic modulus based on different bedding angles and moisture content. Additionally, the damage constitutive model of layered shale was improved. The study revealed that shale’s mechanical properties display anisotropy, which is influenced by the bedding angles and moisture contents. The elastic modulus of the rock increases with the rise of bedding angle, exhibiting a ‘U’-shaped change. Conversely, the mechanical properties of rocks deteriorate, and their brittleness weakens with the increase in moisture content. When the confining pressure increased, the overall mechanical properties of shale were enhanced, and the influence of bedding on shale was weakened, but the deteriorating effect of water on rocks was hardly affected. Based on the above experiments, a predicted model of equivalent elastic modulus of shale considering the coupling effect of bedding and different moisture contents was proposed, which could effectively predict the elastic modulus of layered shale with different moisture content under different confining pressures. Furthermore, based on the predicted model of elastic modulus, an improved damage constitutive model of layered shale under triaxial loading was established, and the damage accumulation trend of layered shale was obtained, which showed an “S”-shaped change with strain. Under the coupling effect of bedding and different moisture contents, the damage of shale was advanced, but the accumulation rate of damage slowed down. With the increase of confining pressure, the influence of bedding and moisture content on the damage characteristics of shale decreased, and the damage curves under different conditions gradually tended to isotropy. The developed damage constitutive model for layered shale under different moisture contents provides theoretical support for the study of reservoir fracturing and wellbore stability.
{"title":"Experimental and damage model study of layered shale under different moisture contents","authors":"Qi Xian-yin, Geng Dian-dong, Xu Ming-zhe, Ke Ting","doi":"10.1177/10567895241245753","DOIUrl":"https://doi.org/10.1177/10567895241245753","url":null,"abstract":"To investigate the mechanical properties and damage evolution law of layered shale under varying moisture contents, we conducted triaxial compression experiments on rock samples with different bedding angles and moisture levels. This study analyzed the variations in mechanical properties of layered shale under different conditions, and established a predicted model for elastic modulus based on different bedding angles and moisture content. Additionally, the damage constitutive model of layered shale was improved. The study revealed that shale’s mechanical properties display anisotropy, which is influenced by the bedding angles and moisture contents. The elastic modulus of the rock increases with the rise of bedding angle, exhibiting a ‘U’-shaped change. Conversely, the mechanical properties of rocks deteriorate, and their brittleness weakens with the increase in moisture content. When the confining pressure increased, the overall mechanical properties of shale were enhanced, and the influence of bedding on shale was weakened, but the deteriorating effect of water on rocks was hardly affected. Based on the above experiments, a predicted model of equivalent elastic modulus of shale considering the coupling effect of bedding and different moisture contents was proposed, which could effectively predict the elastic modulus of layered shale with different moisture content under different confining pressures. Furthermore, based on the predicted model of elastic modulus, an improved damage constitutive model of layered shale under triaxial loading was established, and the damage accumulation trend of layered shale was obtained, which showed an “S”-shaped change with strain. Under the coupling effect of bedding and different moisture contents, the damage of shale was advanced, but the accumulation rate of damage slowed down. With the increase of confining pressure, the influence of bedding and moisture content on the damage characteristics of shale decreased, and the damage curves under different conditions gradually tended to isotropy. The developed damage constitutive model for layered shale under different moisture contents provides theoretical support for the study of reservoir fracturing and wellbore stability.","PeriodicalId":13837,"journal":{"name":"International Journal of Damage Mechanics","volume":"19 1","pages":""},"PeriodicalIF":4.2,"publicationDate":"2024-04-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140550456","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}
Pub Date : 2024-03-18DOI: 10.1177/10567895241235351
Yooseob Song, Jaeheum Yeon, George Z Voyiadjis
A constitutive model for C45 steel alloys is proposed in this work by integrating the effect of damage and a specific phenomenon, so-called dynamic strain aging. For damage modeling, an energy-based isotropic damage model is implemented within a frame of continuum damage mechanics. The total stress is decomposed into athermal and thermal elements. The former includes the additional term for dynamic strain aging. This term is conceptually inspired by the probabilistic nature of dynamic strain aging, and its derivation is micromechanics-based. Both athermal and thermal components are defined as a function of temperature, equivalent plastic strain, and equivalent plastic strain rate because the occurrence and characteristics of dynamic strain aging are dependent on these factors. A finite element solution for the developed model is addressed additionally to further investigate the characteristics of plastic-damage behaviors and dynamic strain aging. The numerical results are compared to the experiments and theoretical predictions for its validation. The modified model developed in this work has largely reduced the number of fitting parameters compared to the previous model originally developed by the authors in 2019. Nevertheless, predictions from the proposed model still capture the experimental data accurately.
{"title":"Theoretical and numerical modeling of the effect of damage and dynamic strain aging on the plastic response of C45 steel alloys","authors":"Yooseob Song, Jaeheum Yeon, George Z Voyiadjis","doi":"10.1177/10567895241235351","DOIUrl":"https://doi.org/10.1177/10567895241235351","url":null,"abstract":"A constitutive model for C45 steel alloys is proposed in this work by integrating the effect of damage and a specific phenomenon, so-called dynamic strain aging. For damage modeling, an energy-based isotropic damage model is implemented within a frame of continuum damage mechanics. The total stress is decomposed into athermal and thermal elements. The former includes the additional term for dynamic strain aging. This term is conceptually inspired by the probabilistic nature of dynamic strain aging, and its derivation is micromechanics-based. Both athermal and thermal components are defined as a function of temperature, equivalent plastic strain, and equivalent plastic strain rate because the occurrence and characteristics of dynamic strain aging are dependent on these factors. A finite element solution for the developed model is addressed additionally to further investigate the characteristics of plastic-damage behaviors and dynamic strain aging. The numerical results are compared to the experiments and theoretical predictions for its validation. The modified model developed in this work has largely reduced the number of fitting parameters compared to the previous model originally developed by the authors in 2019. Nevertheless, predictions from the proposed model still capture the experimental data accurately.","PeriodicalId":13837,"journal":{"name":"International Journal of Damage Mechanics","volume":"17 1","pages":""},"PeriodicalIF":4.2,"publicationDate":"2024-03-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140161881","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}
Pub Date : 2024-03-08DOI: 10.1177/10567895241233836
Kai Chen, Roberto Cudmani, Andres Alfonso Pena Olarte
The study of constitutive relationship and damage degradation is crucial in solving the stability challenges faced in the rock engineering. In this work, the stress-strain relationships of different type of rocks subjected to uniaxial loading processes are investigated in details. Experimental results demonstrate measurements, such as uniaxial compressive strength (UCS), tangent deformation modulus, peak strain, and Poisson’s ratio ([Formula: see text]). A novel piecewise constitutive model is proposed that utilizes both a constitutive model during compaction and a conventional damage model using the strain equivalence assumption and logistic growth theory to represent the characteristics of stress-deformation curves during both compaction and post-compaction stages. The performance of the proposed constitutive models in capturing deformation characteristics of damaged rocks is demonstrated to be more outstanding in comparison to existing models. In all experimental cases discussed in this study, the proposed model outperforms existing reference models in terms of the coefficients of determination ([Formula: see text]), with the former having coefficients of determination greater than 0.95. Furthermore, physical meanings of relevant model parameters are found to be closely associated with properties of experimental stress-strain curves.
{"title":"Mechanical impairment characteristics and a novel constitutive model for rocks subjected to uniaxial loading process","authors":"Kai Chen, Roberto Cudmani, Andres Alfonso Pena Olarte","doi":"10.1177/10567895241233836","DOIUrl":"https://doi.org/10.1177/10567895241233836","url":null,"abstract":"The study of constitutive relationship and damage degradation is crucial in solving the stability challenges faced in the rock engineering. In this work, the stress-strain relationships of different type of rocks subjected to uniaxial loading processes are investigated in details. Experimental results demonstrate measurements, such as uniaxial compressive strength (UCS), tangent deformation modulus, peak strain, and Poisson’s ratio ([Formula: see text]). A novel piecewise constitutive model is proposed that utilizes both a constitutive model during compaction and a conventional damage model using the strain equivalence assumption and logistic growth theory to represent the characteristics of stress-deformation curves during both compaction and post-compaction stages. The performance of the proposed constitutive models in capturing deformation characteristics of damaged rocks is demonstrated to be more outstanding in comparison to existing models. In all experimental cases discussed in this study, the proposed model outperforms existing reference models in terms of the coefficients of determination ([Formula: see text]), with the former having coefficients of determination greater than 0.95. Furthermore, physical meanings of relevant model parameters are found to be closely associated with properties of experimental stress-strain curves.","PeriodicalId":13837,"journal":{"name":"International Journal of Damage Mechanics","volume":"34 1","pages":""},"PeriodicalIF":4.2,"publicationDate":"2024-03-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140067631","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}
Pub Date : 2024-03-05DOI: 10.1177/10567895241235581
Bo Yu, Jian Liang, Jiann-Wen Woody Ju
In this work, a novel method for damage evolution analysis of concrete under uniaxial compression is proposed based on the multi-feature acoustic emission (AE) and the Gaussian mixture model (GMM) clustering. The hierarchical clustering algorithm is adopted to select optimal AE parameters, while multiple features of these parameters are generated through the principal component analysis (PCA). Then the concrete damage signals are separated by using the GMM clustering with multiple features. Meanwhile, the waveform signals associated with concrete damage in each cluster are validated using the Fast Fourier transform (FFT) and the continuous wavelet transform (CWT). Finally, the damage evolution process of concrete under uniaxial compression is divided based on the variation of AE characteristics. The results show that the frequency ranges of signals for micro-cracks, mixed cracks and friction of concrete under uniaxial compression are 20–30 kHz, 20–65 kHz, and 100–120 kHz, respectively. The damage process of concrete under uniaxial compression is divided into three stages according to the inflection points of the cumulative energy curve, namely the initial compaction stage, the crack formation stage and the failure stage.
{"title":"Damage evolution analysis of concrete based on multi-feature acoustic emission and Gaussian mixture model clustering","authors":"Bo Yu, Jian Liang, Jiann-Wen Woody Ju","doi":"10.1177/10567895241235581","DOIUrl":"https://doi.org/10.1177/10567895241235581","url":null,"abstract":"In this work, a novel method for damage evolution analysis of concrete under uniaxial compression is proposed based on the multi-feature acoustic emission (AE) and the Gaussian mixture model (GMM) clustering. The hierarchical clustering algorithm is adopted to select optimal AE parameters, while multiple features of these parameters are generated through the principal component analysis (PCA). Then the concrete damage signals are separated by using the GMM clustering with multiple features. Meanwhile, the waveform signals associated with concrete damage in each cluster are validated using the Fast Fourier transform (FFT) and the continuous wavelet transform (CWT). Finally, the damage evolution process of concrete under uniaxial compression is divided based on the variation of AE characteristics. The results show that the frequency ranges of signals for micro-cracks, mixed cracks and friction of concrete under uniaxial compression are 20–30 kHz, 20–65 kHz, and 100–120 kHz, respectively. The damage process of concrete under uniaxial compression is divided into three stages according to the inflection points of the cumulative energy curve, namely the initial compaction stage, the crack formation stage and the failure stage.","PeriodicalId":13837,"journal":{"name":"International Journal of Damage Mechanics","volume":"26 1","pages":""},"PeriodicalIF":4.2,"publicationDate":"2024-03-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140043464","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}
Pub Date : 2024-02-29DOI: 10.1177/10567895241234163
Bin Shang, Zhiwu Zhu, Bin Li, Fulai Zhang, Tao Li
The soil matrix, salt crystals, ice crystals, and pore solutions constitute the composite geological material of saturated saline frozen soil. The destruction mode and dynamic constitutive model of saturated saline frozen soil need to be studied because infrastructure construction is increasingly being extended to regions with saturated saline frozen soil. Based on the split Hopkinson pressure bar device, uniaxial impact compression tests were conducted on frozen soil samples with different salt contents under different strain rates. The strain rate of saturated saline frozen soil must be emphasized based on the results. The gradient of the elastic segment and maximum stress of the soil are negatively correlated with the salt content increase. To further explore the failure mechanism, the study examined the damage and failure behavior of saturated saline frozen soil, along with the absorption energy in the failure process. According to the test results, the saturated saline frozen soil was similar to a particle-reinforced composite. Subsequently, the debonding damage of the ice–salt eutectic and the mechanical–chemical damage of the soil matrix were considered. The test results could be predicted accurately from the results of the model, verifying that the influences of the salt content and strain rate are reasonably considered by the constructed model.
{"title":"Dynamic constitutive model of saturated saline frozen soil under uniaxial impact loading","authors":"Bin Shang, Zhiwu Zhu, Bin Li, Fulai Zhang, Tao Li","doi":"10.1177/10567895241234163","DOIUrl":"https://doi.org/10.1177/10567895241234163","url":null,"abstract":"The soil matrix, salt crystals, ice crystals, and pore solutions constitute the composite geological material of saturated saline frozen soil. The destruction mode and dynamic constitutive model of saturated saline frozen soil need to be studied because infrastructure construction is increasingly being extended to regions with saturated saline frozen soil. Based on the split Hopkinson pressure bar device, uniaxial impact compression tests were conducted on frozen soil samples with different salt contents under different strain rates. The strain rate of saturated saline frozen soil must be emphasized based on the results. The gradient of the elastic segment and maximum stress of the soil are negatively correlated with the salt content increase. To further explore the failure mechanism, the study examined the damage and failure behavior of saturated saline frozen soil, along with the absorption energy in the failure process. According to the test results, the saturated saline frozen soil was similar to a particle-reinforced composite. Subsequently, the debonding damage of the ice–salt eutectic and the mechanical–chemical damage of the soil matrix were considered. The test results could be predicted accurately from the results of the model, verifying that the influences of the salt content and strain rate are reasonably considered by the constructed model.","PeriodicalId":13837,"journal":{"name":"International Journal of Damage Mechanics","volume":"1 1","pages":""},"PeriodicalIF":4.2,"publicationDate":"2024-02-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140000928","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}
Concrete-filled steel tube (CFST) widely applied in engineering structures due to its superior behavior requires monitoring and assessment for damage level. Here, the acoustic emission (AE) technique was used to monitor the fracture process of concrete core in CFST stub columns subjected to axial compression. Test and analyzed results show that the damage process of CFST specimens can be divided into four stages: compaction, elastic-plastic stage, strengthening and secondary strengthening. In the elastic-plastic stage, the evolutionary features of the AE event rate, cumulative energy, Ib-value and crack classification are capable of providing an early warning for cracked concrete core. Full crack propagation can be identified by the rapid increase in the proportion of shear cracks near the inflection point of load, which is impermissible in engineering structures. According to the analyses of the AE event rate and signal intensity in the elastic-plastic stage, the confinement of steel tube with thicker wall thickness or higher strength is delayed, which implies that this confinement is suggested to be triggered early. It is indicated that the AE technique has the potential to monitor and evaluate the damage process of CFST stub columns under axial compression, which can provide additional insight into the failure mechanism and assist in the scheme of repairs.
{"title":"Damage analysis of axially compressed concrete-filled steel tube stub columns based on acoustic emission","authors":"Yanjun Chang, Enchao Rong, Wanli Chen, Xiaojun Ke, Kaizhong Xie","doi":"10.1177/10567895241234002","DOIUrl":"https://doi.org/10.1177/10567895241234002","url":null,"abstract":"Concrete-filled steel tube (CFST) widely applied in engineering structures due to its superior behavior requires monitoring and assessment for damage level. Here, the acoustic emission (AE) technique was used to monitor the fracture process of concrete core in CFST stub columns subjected to axial compression. Test and analyzed results show that the damage process of CFST specimens can be divided into four stages: compaction, elastic-plastic stage, strengthening and secondary strengthening. In the elastic-plastic stage, the evolutionary features of the AE event rate, cumulative energy, Ib-value and crack classification are capable of providing an early warning for cracked concrete core. Full crack propagation can be identified by the rapid increase in the proportion of shear cracks near the inflection point of load, which is impermissible in engineering structures. According to the analyses of the AE event rate and signal intensity in the elastic-plastic stage, the confinement of steel tube with thicker wall thickness or higher strength is delayed, which implies that this confinement is suggested to be triggered early. It is indicated that the AE technique has the potential to monitor and evaluate the damage process of CFST stub columns under axial compression, which can provide additional insight into the failure mechanism and assist in the scheme of repairs.","PeriodicalId":13837,"journal":{"name":"International Journal of Damage Mechanics","volume":"261 1","pages":""},"PeriodicalIF":4.2,"publicationDate":"2024-02-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140000926","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}
Pub Date : 2024-02-28DOI: 10.1177/10567895241234382
Bin Liu, Yancheng Liu, Qiyun Ao, Tengfei Yang, Rui Yan, Yongsheng Liu
The ingested particles or debris will cause high-speed & low-energy impact to the hot end components of aeroengine. Few literature focus on the projectile impact of SiC/SiC with Environmental Barrier Coating(EBC). The impact of 2 mm projectile was specially studied for Si/Yb2Si2O7/Yb2SiO5-SiC/SiC. Gas gun system was used to conduct impact testing at the speed of 3 m/s∼353m/s. The optical microscope, Scanning Electronic Microscope(SEM), micro CT were used to observe the impact and tension after impact(TAI) damage. For TAI, Digital Image Correlation (DIC) was used to conduct the full-field strain detection around the impact point. Meanwhile, the Smoothed Particle Hydrodynamics (SPH) methodology was programmed in C++ and developed to simulate SiC/SiC impact problem by introducing modified Hashin-Rotem criteria, extending interface method to 3D and adding GPU accelerated algorithm. The results indicate that threshold velocities of EBC huge peeling and SiC/SiC penetration are different, TAI residual strength also has extinct threshold at the velocity of 246 m/s with 37.1% declining extent, and the impact pit depth of SPH simulation is in good agreement with the experiment.
{"title":"Experimental and numerical study on projectile impact damage of EBC-SiC/SiC","authors":"Bin Liu, Yancheng Liu, Qiyun Ao, Tengfei Yang, Rui Yan, Yongsheng Liu","doi":"10.1177/10567895241234382","DOIUrl":"https://doi.org/10.1177/10567895241234382","url":null,"abstract":"The ingested particles or debris will cause high-speed & low-energy impact to the hot end components of aeroengine. Few literature focus on the projectile impact of SiC/SiC with Environmental Barrier Coating(EBC). The impact of 2 mm projectile was specially studied for Si/Yb<jats:sub>2</jats:sub>Si<jats:sub>2</jats:sub>O<jats:sub>7/</jats:sub>Yb<jats:sub>2</jats:sub>SiO<jats:sub>5</jats:sub>-SiC/SiC. Gas gun system was used to conduct impact testing at the speed of 3 m/s∼353m/s. The optical microscope, Scanning Electronic Microscope(SEM), micro CT were used to observe the impact and tension after impact(TAI) damage. For TAI, Digital Image Correlation (DIC) was used to conduct the full-field strain detection around the impact point. Meanwhile, the Smoothed Particle Hydrodynamics (SPH) methodology was programmed in C++ and developed to simulate SiC/SiC impact problem by introducing modified Hashin-Rotem criteria, extending interface method to 3D and adding GPU accelerated algorithm. The results indicate that threshold velocities of EBC huge peeling and SiC/SiC penetration are different, TAI residual strength also has extinct threshold at the velocity of 246 m/s with 37.1% declining extent, and the impact pit depth of SPH simulation is in good agreement with the experiment.","PeriodicalId":13837,"journal":{"name":"International Journal of Damage Mechanics","volume":"4 1","pages":""},"PeriodicalIF":4.2,"publicationDate":"2024-02-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139994071","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}
Pub Date : 2024-02-28DOI: 10.1177/10567895241233975
Hong-Bo Huang, Zheng-Ming Huang, Yong-Ping Wan
This work deals with the fiber ends debonding-induced elastic moduli degradation of a short fiber reinforced composite (SFRC). The strain fields of the matrix in a representative volume element (RVE) of the SFRC are determined from an imaginary fiber technique. By using the debonding boundary conditions, the debonded modulus of the composite is derived, which is affected by not only the far-field but also the transient solutions for the longitudinal strain of the matrix. Particularly, the imaginary fiber technique provides unbounded solution for a moderately large fiber aspect ratio. This is resolved by separating the RVE along the fiber direction into two domains. Combining the longitudinal strains in both domains, the longitudinal modulus is determined, and the longitudinal bridging tensor element in the micromechanics Bridging Model is amended. Five elastic moduli of an SFRC after the fiber end debonding are obtained on the amended Bridging Model. The effects of the fiber volume fraction, fiber aspect ratio, and fiber-to-matrix modulus ratio on the end-debonded longitudinal modulus, transverse modulus, and longitudinal Poisson’s ratio are investigated.
{"title":"Elastic moduli prediction of a short fiber composite with interface debonding at fiber ends","authors":"Hong-Bo Huang, Zheng-Ming Huang, Yong-Ping Wan","doi":"10.1177/10567895241233975","DOIUrl":"https://doi.org/10.1177/10567895241233975","url":null,"abstract":"This work deals with the fiber ends debonding-induced elastic moduli degradation of a short fiber reinforced composite (SFRC). The strain fields of the matrix in a representative volume element (RVE) of the SFRC are determined from an imaginary fiber technique. By using the debonding boundary conditions, the debonded modulus of the composite is derived, which is affected by not only the far-field but also the transient solutions for the longitudinal strain of the matrix. Particularly, the imaginary fiber technique provides unbounded solution for a moderately large fiber aspect ratio. This is resolved by separating the RVE along the fiber direction into two domains. Combining the longitudinal strains in both domains, the longitudinal modulus is determined, and the longitudinal bridging tensor element in the micromechanics Bridging Model is amended. Five elastic moduli of an SFRC after the fiber end debonding are obtained on the amended Bridging Model. The effects of the fiber volume fraction, fiber aspect ratio, and fiber-to-matrix modulus ratio on the end-debonded longitudinal modulus, transverse modulus, and longitudinal Poisson’s ratio are investigated.","PeriodicalId":13837,"journal":{"name":"International Journal of Damage Mechanics","volume":"82 1","pages":""},"PeriodicalIF":4.2,"publicationDate":"2024-02-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139994099","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}
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