Pub Date : 2024-10-31DOI: 10.1016/j.ijimpeng.2024.105159
Weiting Gao , Zheming Zhu , Meng Wang , Lei Zhou , Li Ren , Yuntao Wang
Hole defects can lead to non-uniform strain distribution under the impact load, thereby influencing crack propagation behavior. In this paper, 2D-DIC technology was employed to examine the effects of holes of varying sizes and loading rates on crack dynamics in PMMA materials, aiming to elucidate detailed knowledge into the characteristics of crack propagation under complex strain fields. Through DIC analyses, the dynamic evolution of strain fields around the crack tip and hole periphery could be precisely captured, enabling tracking of crack propagation behavior including crack propagation velocity, crack propagation path, and crack deflection angle. It is concluded that the non-uniform strain zones generated by holes exert both inhibitory and attracting effects on crack growth. The influence of non-uniform strain zones on crack propagation increases with the elevation of loading rate and hole size. However, as the loading rate increases, the kinetic energy of the crack itself also increases, necessitating sufficiently large hole sizes to effectively influence crack propagation. Overall, this study provides a detailed experimental explanation of the effects of holes on cracks, which will aid engineers in maximizing the positive impact of holes on material performance and their application in the design of microstructure materials.
{"title":"Investigation of the influence of non-uniform strain zone on the crack propagation of PMMA material based on 2D-DIC","authors":"Weiting Gao , Zheming Zhu , Meng Wang , Lei Zhou , Li Ren , Yuntao Wang","doi":"10.1016/j.ijimpeng.2024.105159","DOIUrl":"10.1016/j.ijimpeng.2024.105159","url":null,"abstract":"<div><div>Hole defects can lead to non-uniform strain distribution under the impact load, thereby influencing crack propagation behavior. In this paper, 2D-DIC technology was employed to examine the effects of holes of varying sizes and loading rates on crack dynamics in PMMA materials, aiming to elucidate detailed knowledge into the characteristics of crack propagation under complex strain fields. Through DIC analyses, the dynamic evolution of strain fields around the crack tip and hole periphery could be precisely captured, enabling tracking of crack propagation behavior including crack propagation velocity, crack propagation path, and crack deflection angle. It is concluded that the non-uniform strain zones generated by holes exert both inhibitory and attracting effects on crack growth. The influence of non-uniform strain zones on crack propagation increases with the elevation of loading rate and hole size. However, as the loading rate increases, the kinetic energy of the crack itself also increases, necessitating sufficiently large hole sizes to effectively influence crack propagation. Overall, this study provides a detailed experimental explanation of the effects of holes on cracks, which will aid engineers in maximizing the positive impact of holes on material performance and their application in the design of microstructure materials.</div></div>","PeriodicalId":50318,"journal":{"name":"International Journal of Impact Engineering","volume":"196 ","pages":"Article 105159"},"PeriodicalIF":5.1,"publicationDate":"2024-10-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142662694","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 : 2024-10-30DOI: 10.1016/j.ijimpeng.2024.105151
Qibo Zhang , Ye Yuan
In the present study, the ballistic perforation resistance of steel/titanium/aluminum (STA) multilayer protective systems impacted by spherical, ogival, conical, and blunt projectiles was investigated experimentally, numerically, and analytically. The targets were manufactured via explosive welding technique to achieve a strong interfacial strength. The projectile nose shape was found to significantly affect the failure modes and ballistic limit velocities of the STA composite plate. Detailed three-dimensional finite element simulations were performed to provide insights into the penetration process and energy absorption characteristics of the STA composite plate. An analytical model was developed to predict the entry and exit penetration phases of a rigid projectile of different nose shapes into the STA target through ductile hole expansion. The model simplified the STA composite plate to be an equivalent monolithic based on the weighting of material resistance and specific cavitation energy in each layer. The analytical and numerical predictions of the residual velocity were in excellent agreement with the experimental data. The predicted evolution of projectile velocity with penetration depth was found to be in satisfactory correlation with those from the numerical simulation. The proposed analytical model shall be useful for designers of multilayer metallic protective structures against fragments from improvised explosive devices.
本研究通过实验、数值和分析方法研究了钢/钛/铝（STA）多层防护系统在受到球形、椭圆形、锥形和钝形弹丸冲击时的抗弹道穿孔能力。目标是通过爆炸焊接技术制造的，以获得较强的界面强度。研究发现，弹头形状对 STA 复合材料板的失效模式和弹道极限速度有显著影响。研究人员进行了详细的三维有限元模拟，以深入了解 STA 复合板的穿透过程和能量吸收特性。建立了一个分析模型，用于预测不同弹头形状的刚性弹丸通过韧性孔扩展进入 STA 靶件的进入和退出穿透阶段。该模型根据各层材料阻力和比空化能的权重，将 STA 复合板简化为等效整体。残余速度的分析和数值预测与实验数据非常吻合。射弹速度随穿透深度的变化预测结果与数值模拟结果的相关性令人满意。所提出的分析模型对设计多层金属防护结构以防止简易爆炸装置碎片的产生很有帮助。
{"title":"Effect of projectile nose shape on ballistic resistance of multi-layered explosively welded plates","authors":"Qibo Zhang , Ye Yuan","doi":"10.1016/j.ijimpeng.2024.105151","DOIUrl":"10.1016/j.ijimpeng.2024.105151","url":null,"abstract":"<div><div>In the present study, the ballistic perforation resistance of steel/titanium/aluminum (STA) multilayer protective systems impacted by spherical, ogival, conical, and blunt projectiles was investigated experimentally, numerically, and analytically. The targets were manufactured via explosive welding technique to achieve a strong interfacial strength. The projectile nose shape was found to significantly affect the failure modes and ballistic limit velocities of the STA composite plate. Detailed three-dimensional finite element simulations were performed to provide insights into the penetration process and energy absorption characteristics of the STA composite plate. An analytical model was developed to predict the entry and exit penetration phases of a rigid projectile of different nose shapes into the STA target through ductile hole expansion. The model simplified the STA composite plate to be an equivalent monolithic based on the weighting of material resistance and specific cavitation energy in each layer. The analytical and numerical predictions of the residual velocity were in excellent agreement with the experimental data. The predicted evolution of projectile velocity with penetration depth was found to be in satisfactory correlation with those from the numerical simulation. The proposed analytical model shall be useful for designers of multilayer metallic protective structures against fragments from improvised explosive devices.</div></div>","PeriodicalId":50318,"journal":{"name":"International Journal of Impact Engineering","volume":"196 ","pages":"Article 105151"},"PeriodicalIF":5.1,"publicationDate":"2024-10-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142593295","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 : 2024-10-30DOI: 10.1016/j.ijimpeng.2024.105157
Zihao Li , Tianhui Zhang , Bo Tang , Zhifang Liu , Zhihua Wang , Shiqiang Li
Experimental, theoretical and numerical simulations were carried out to investigate the dynamic response and blast resistance for the cylindrical sandwich shells with toroidal tubular cores under internal blast loading. The typical deformation modes of internal/external shells and toroidal tubular core layers were observed through experiments. A theoretical model considering the circumferential plastic membrane forces and the axial moment components was performed to predict the blast response of sandwich shells. The mid-points deflections and velocities of internal/external shells obtained by theoretical predictions are consistent with the experimental and numerical results. Influences of wall thicknesses of internal/external shells and the axial/radial gradient of toroidal tubular cores on the blast resistance of single and triple layers sandwich shells were investigated by numerical simulations. The results show that the negative gradient structures have the smallest normalized deflection, while the hybrid gradient structures have the highest energy absorption. On this basis, multi-objective optimization of the sandwich shells was carried out by combining the response surface method (RSM) and the multi-objective genetic algorithm (MOGA). The optimization results yielded a trade-off between deformation, energy absorption and structural mass, and demonstrated the advantages of the “Pareto front” in these design cases.
{"title":"Blast response and optimization of cylindrical sandwich shells with toroidal tubular cores","authors":"Zihao Li , Tianhui Zhang , Bo Tang , Zhifang Liu , Zhihua Wang , Shiqiang Li","doi":"10.1016/j.ijimpeng.2024.105157","DOIUrl":"10.1016/j.ijimpeng.2024.105157","url":null,"abstract":"<div><div>Experimental, theoretical and numerical simulations were carried out to investigate the dynamic response and blast resistance for the cylindrical sandwich shells with toroidal tubular cores under internal blast loading. The typical deformation modes of internal/external shells and toroidal tubular core layers were observed through experiments. A theoretical model considering the circumferential plastic membrane forces and the axial moment components was performed to predict the blast response of sandwich shells. The mid-points deflections and velocities of internal/external shells obtained by theoretical predictions are consistent with the experimental and numerical results. Influences of wall thicknesses of internal/external shells and the axial/radial gradient of toroidal tubular cores on the blast resistance of single and triple layers sandwich shells were investigated by numerical simulations. The results show that the negative gradient structures have the smallest normalized deflection, while the hybrid gradient structures have the highest energy absorption. On this basis, multi-objective optimization of the sandwich shells was carried out by combining the response surface method (RSM) and the multi-objective genetic algorithm (MOGA). The optimization results yielded a trade-off between deformation, energy absorption and structural mass, and demonstrated the advantages of the “Pareto front” in these design cases.</div></div>","PeriodicalId":50318,"journal":{"name":"International Journal of Impact Engineering","volume":"196 ","pages":"Article 105157"},"PeriodicalIF":5.1,"publicationDate":"2024-10-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142662738","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}
Polymeric composite sandwich materials are critical for marine structures, but their behavior under near-field underwater explosions is not well understood. This study investigates the dynamic response of carbon-fiber-reinforced sandwich composites with varying core densities subjected to near-field underwater explosions. Lab-scale experiments were conducted at two explosive stand-off distances using high-speed imaging and Digital Image Correlation (DIC) to capture the evolution of gas bubble dynamics, surface cavitation, and structural deformation. Results showed that reducing the stand-off distance led to a 0.7 ms increase in gas bubble period, along with an 80 mm increase in horizontal migration of the bubble, while vertical migration remained unaffected. The interaction between the gas bubble and surface cavitation, driven by fluid-structure interaction (FSI), significantly influenced the structural response. In particular, the simultaneous collapse of the gas bubble and surface cavitation resulted in higher localized impulsive loading, causing catastrophic failure in low-density core panels. Meanwhile, panels with higher core densities exhibited a 40 % reduction in out-of-plane deflection, demonstrating enhanced resistance to blast loading. This study provides new insights into the fluid-structure interaction mechanisms that occur during near-field underwater explosions and offers a basis for improving the design of marine structures by optimizing material selection and geometric configurations. These findings contribute to a deeper understanding of shock mitigation strategies in composite materials and inform future research in marine structural design under extreme loading conditions.
{"title":"Near-field underwater explosion and its interaction with a sandwich composite plate","authors":"Akash Pandey , Piyush Wanchoo , Helio Matos , James LeBlanc , Arun Shukla","doi":"10.1016/j.ijimpeng.2024.105155","DOIUrl":"10.1016/j.ijimpeng.2024.105155","url":null,"abstract":"<div><div>Polymeric composite sandwich materials are critical for marine structures, but their behavior under near-field underwater explosions is not well understood. This study investigates the dynamic response of carbon-fiber-reinforced sandwich composites with varying core densities subjected to near-field underwater explosions. Lab-scale experiments were conducted at two explosive stand-off distances using high-speed imaging and Digital Image Correlation (DIC) to capture the evolution of gas bubble dynamics, surface cavitation, and structural deformation. Results showed that reducing the stand-off distance led to a 0.7 ms increase in gas bubble period, along with an 80 mm increase in horizontal migration of the bubble, while vertical migration remained unaffected. The interaction between the gas bubble and surface cavitation, driven by fluid-structure interaction (FSI), significantly influenced the structural response. In particular, the simultaneous collapse of the gas bubble and surface cavitation resulted in higher localized impulsive loading, causing catastrophic failure in low-density core panels. Meanwhile, panels with higher core densities exhibited a 40 % reduction in out-of-plane deflection, demonstrating enhanced resistance to blast loading. This study provides new insights into the fluid-structure interaction mechanisms that occur during near-field underwater explosions and offers a basis for improving the design of marine structures by optimizing material selection and geometric configurations. These findings contribute to a deeper understanding of shock mitigation strategies in composite materials and inform future research in marine structural design under extreme loading conditions.</div></div>","PeriodicalId":50318,"journal":{"name":"International Journal of Impact Engineering","volume":"196 ","pages":"Article 105155"},"PeriodicalIF":5.1,"publicationDate":"2024-10-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142662739","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 : 2024-10-28DOI: 10.1016/j.ijimpeng.2024.105150
Ioan I. Feier , Michael L. Anderson , James R. Boudrie , Erin M. Jarrett-Izzi , Jonathon L. Gabriel , Kaleb D. Overby , Jason H. Niebuhr , Paul T. Mead , Kalyan R. Kota , Thomas E. Lacy Jr.
The increasingly congested orbital environment around Earth threatens the safety of space assets. Micrometeoroids and orbital debris (MMOD) less than 1 cm but traveling at hypervelocities pose a serious but defensible hazard. Traditional shields are installed during spacecraft assembly and must survive launch loads, constraining their size, shape, and ultimately, effectiveness. Recent advances in on-orbit additive manufacturing have created new opportunities for shield design and deployment. This work describes the modeling and testing of additively manufactured polyetherimide shields. The finite element code CTH was used to model hypervelocity impacts (HVIs) of such shields, and though imperfect, the models were useful for shield design. Several shield designs were additively manufactured and underwent HVI testing with a two-stage light gas gun in the regime of 4 mm diameter aluminum projectile impacts at 5 - 6.5 km/s. All successfully survived the HVIs, indicating their potential effectiveness as MMOD spacecraft shielding.
{"title":"Design and evaluation of additively manufactured polyetherimide orbital debris shielding for spacecraft","authors":"Ioan I. Feier , Michael L. Anderson , James R. Boudrie , Erin M. Jarrett-Izzi , Jonathon L. Gabriel , Kaleb D. Overby , Jason H. Niebuhr , Paul T. Mead , Kalyan R. Kota , Thomas E. Lacy Jr.","doi":"10.1016/j.ijimpeng.2024.105150","DOIUrl":"10.1016/j.ijimpeng.2024.105150","url":null,"abstract":"<div><div>The increasingly congested orbital environment around Earth threatens the safety of space assets. Micrometeoroids and orbital debris (MMOD) less than 1 cm but traveling at hypervelocities pose a serious but defensible hazard. Traditional shields are installed during spacecraft assembly and must survive launch loads, constraining their size, shape, and ultimately, effectiveness. Recent advances in on-orbit additive manufacturing have created new opportunities for shield design and deployment. This work describes the modeling and testing of additively manufactured polyetherimide shields. The finite element code CTH was used to model hypervelocity impacts (HVIs) of such shields, and though imperfect, the models were useful for shield design. Several shield designs were additively manufactured and underwent HVI testing with a two-stage light gas gun in the regime of 4 mm diameter aluminum projectile impacts at 5 - 6.5 km/s. All successfully survived the HVIs, indicating their potential effectiveness as MMOD spacecraft shielding.</div></div>","PeriodicalId":50318,"journal":{"name":"International Journal of Impact Engineering","volume":"196 ","pages":"Article 105150"},"PeriodicalIF":5.1,"publicationDate":"2024-10-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142593296","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 : 2024-10-26DOI: 10.1016/j.ijimpeng.2024.105158
Lin Lang , Zhenwu Luo , Quan Yuan , Zheming Zhu , Lei Zhou , Qian Xu , Xuebing Tang , Hongxia Gao , Jixing Cao , Zihong Gan
Brittle materials such as rock or concrete contain a large number of micro-cracks, voids, and other defects. Under external impacting loads, the interaction between fissures and holes affects the bearing capacity and stability of Engineering structures. To study the interaction mechanism between moving cracks and circular holes, a large-size semi-circular notched with a fissure and double circular hole (SNFDH) specimen was suggested in this research, and the dynamic fracture tests were carried out on the SNFDH specimens with different double circular hole spacing (35 mm, 40 mm, 45 mm, 50 mm, 55 mm, 60 mm, and 70 mm) using a drop hammer impact test device. Crack propagation gauges were employed to track the time and velocity at which the crack propagated along its trajectory. Dynamic Drucker-Prager yield criterion and cumulative damage failure criterion were used in the numerical simulation of the SNFDH concrete materials. The program AUTODYN was employed to simulate the crack growth characteristics when a crack encounters the double hole. The program ABAQUS was applied to calculate the dynamic fracture parameters of cracks. The test results manifest that the crack propagating trajectory has three different characteristics according to the double hole spacing; the double circular hole has an arresting function for a moving crack; the size of the double hole spacing has a significant effect on the crack propagating velocity, crack propagating length, dynamic stress intensity factor and dynamic energy release rate; the configuration of the SNFDH specimen can be used to investigate the crack arrest mechanism when moving crack encountering double holes.
{"title":"Crack arrest characteristics and dynamic fracture parameters of moving cracks encountering double holes under impact loads","authors":"Lin Lang , Zhenwu Luo , Quan Yuan , Zheming Zhu , Lei Zhou , Qian Xu , Xuebing Tang , Hongxia Gao , Jixing Cao , Zihong Gan","doi":"10.1016/j.ijimpeng.2024.105158","DOIUrl":"10.1016/j.ijimpeng.2024.105158","url":null,"abstract":"<div><div>Brittle materials such as rock or concrete contain a large number of micro-cracks, voids, and other defects. Under external impacting loads, the interaction between fissures and holes affects the bearing capacity and stability of Engineering structures. To study the interaction mechanism between moving cracks and circular holes, a large-size semi-circular notched with a fissure and double circular hole (SNFDH) specimen was suggested in this research, and the dynamic fracture tests were carried out on the SNFDH specimens with different double circular hole spacing (35 mm, 40 mm, 45 mm, 50 mm, 55 mm, 60 mm, and 70 mm) using a drop hammer impact test device. Crack propagation gauges were employed to track the time and velocity at which the crack propagated along its trajectory. Dynamic Drucker-Prager yield criterion and cumulative damage failure criterion were used in the numerical simulation of the SNFDH concrete materials. The program AUTODYN was employed to simulate the crack growth characteristics when a crack encounters the double hole. The program ABAQUS was applied to calculate the dynamic fracture parameters of cracks. The test results manifest that the crack propagating trajectory has three different characteristics according to the double hole spacing; the double circular hole has an arresting function for a moving crack; the size of the double hole spacing has a significant effect on the crack propagating velocity, crack propagating length, dynamic stress intensity factor and dynamic energy release rate; the configuration of the SNFDH specimen can be used to investigate the crack arrest mechanism when moving crack encountering double holes.</div></div>","PeriodicalId":50318,"journal":{"name":"International Journal of Impact Engineering","volume":"195 ","pages":"Article 105158"},"PeriodicalIF":5.1,"publicationDate":"2024-10-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142551836","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 : 2024-10-24DOI: 10.1016/j.ijimpeng.2024.105146
Vincenzo Della Corte , Stefano Ferretti , Alice Maria Piccirillo , Alessandra Rotundi , Ivano Bertini , Fabio Cozzolino , Alessio Ferone , Stefano Fiscale , Andrea Longobardo , Laura Inno , Eleonora Ammannito , Giuseppe Sindoni , Chiara Grappasonni , Matthew Sylvest , Manish R. Patel , Hanno Ertel , Mark Millinger , Hanna Rothkaehl
The dust ejected by cometary nuclei encodes valuable information on the formation and evolution of the early Solar System. Multiple short-period comets have been studied in situ, but several perihelion passages considerably modified their pristine condition. Comet Interceptor is the first space mission selected by the European Space Agency to study a pristine dynamically new comet in situ. During a fast flyby through the comet coma, hypervelocity impacts with dust particles will represent not only an important source of information, but also a serious hazard to the spacecraft and its payload. Here we discuss the assessment tests performed on the dust shield of the Dust Impact Sensor and Counter instrument (DISC), part of the Comet Interceptor payload, which will be directly exposed to the cometary dust flux. Using a Light-Gas Gun, we shot mm-sized particles at 5 km/s, transferring momenta and kinetic energies representative of those foreseen for the mission. The impact effects on the DISC breadboard were compared to theoretical predictions by a ballistic limit equation for hypervelocity impacts. We find that, with a simple improvement in the dust shield design, DISC is compatible with the expected cometary environment.
{"title":"Performance assessment of an innovative light and compact dust shield for DISC onboard Comet Interceptor/ESA space probes","authors":"Vincenzo Della Corte , Stefano Ferretti , Alice Maria Piccirillo , Alessandra Rotundi , Ivano Bertini , Fabio Cozzolino , Alessio Ferone , Stefano Fiscale , Andrea Longobardo , Laura Inno , Eleonora Ammannito , Giuseppe Sindoni , Chiara Grappasonni , Matthew Sylvest , Manish R. Patel , Hanno Ertel , Mark Millinger , Hanna Rothkaehl","doi":"10.1016/j.ijimpeng.2024.105146","DOIUrl":"10.1016/j.ijimpeng.2024.105146","url":null,"abstract":"<div><div>The dust ejected by cometary nuclei encodes valuable information on the formation and evolution of the early Solar System. Multiple short-period comets have been studied in situ, but several perihelion passages considerably modified their pristine condition. Comet Interceptor is the first space mission selected by the European Space Agency to study a pristine dynamically new comet in situ. During a fast flyby through the comet coma, hypervelocity impacts with dust particles will represent not only an important source of information, but also a serious hazard to the spacecraft and its payload. Here we discuss the assessment tests performed on the dust shield of the Dust Impact Sensor and Counter instrument (DISC), part of the Comet Interceptor payload, which will be directly exposed to the cometary dust flux. Using a Light-Gas Gun, we shot mm-sized particles at <span><math><mrow><mo>∼</mo><mspace></mspace></mrow></math></span>5 km/s, transferring momenta and kinetic energies representative of those foreseen for the mission. The impact effects on the DISC breadboard were compared to theoretical predictions by a ballistic limit equation for hypervelocity impacts. We find that, with a simple improvement in the dust shield design, DISC is compatible with the expected cometary environment.</div></div>","PeriodicalId":50318,"journal":{"name":"International Journal of Impact Engineering","volume":"195 ","pages":"Article 105146"},"PeriodicalIF":5.1,"publicationDate":"2024-10-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142561352","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}
Pub Date : 2024-10-23DOI: 10.1016/j.ijimpeng.2024.105145
Lei Yan , Li Chen , Boyu Chen , Qin Fang
Concrete demonstrates complex dynamic mechanical behaviors under the influence of blast or impact loads, and there are inherent limitations in experimental and theoretical methods when dealing with highly nonlinear problems. As computational technologies and mechanics continue to evolve, it is possible to conduct high-fidelity simulations of the transient response of concrete structures subjected to intense dynamic loads. Such simulations play a crucial role in revealing the propagation laws of stress waves, the progression of damage, the mechanisms of structural failure, and in conducting protective engineering design. An accurate concrete material model is essential for conducting numerical studies. This article reviews the development of high-pressure dynamic constitutive models for concrete in recent years from both experimental research and theoretical modeling perspectives, focusing on the analysis and evaluation of the modeling methods and main shortcomings of the equation of state(EOS), strength model, and damage model. Using single-element numerical simulations under a single loading path and numerical calculations of engineering cases under complex loading paths, a systematic analysis and comparison were conducted on the predictive capabilities of the HJC, RHT, KCC, and CSC models, as well as the newly developed Kong-Fang and Yan-Chen models. It pointed out the impact of high-pressure mechanical behavior of concrete and the cumulative effect of damage under hydrostatic pressure on the calculation results. Finally, a discussion was conducted on the inherent flaws, applicability, and research difficulties of local constitutive models of concrete in the finite element method. This provides a reference for the selection and research of constitutive models when conducting numerical analysis of the blast and impact resistance of concrete structures.
{"title":"Analysis and evaluation of suitability of high-pressure dynamic constitutive model for concrete under blast and impact loading","authors":"Lei Yan , Li Chen , Boyu Chen , Qin Fang","doi":"10.1016/j.ijimpeng.2024.105145","DOIUrl":"10.1016/j.ijimpeng.2024.105145","url":null,"abstract":"<div><div>Concrete demonstrates complex dynamic mechanical behaviors under the influence of blast or impact loads, and there are inherent limitations in experimental and theoretical methods when dealing with highly nonlinear problems. As computational technologies and mechanics continue to evolve, it is possible to conduct high-fidelity simulations of the transient response of concrete structures subjected to intense dynamic loads. Such simulations play a crucial role in revealing the propagation laws of stress waves, the progression of damage, the mechanisms of structural failure, and in conducting protective engineering design. An accurate concrete material model is essential for conducting numerical studies. This article reviews the development of high-pressure dynamic constitutive models for concrete in recent years from both experimental research and theoretical modeling perspectives, focusing on the analysis and evaluation of the modeling methods and main shortcomings of the equation of state(EOS), strength model, and damage model. Using single-element numerical simulations under a single loading path and numerical calculations of engineering cases under complex loading paths, a systematic analysis and comparison were conducted on the predictive capabilities of the HJC, RHT, KCC, and CSC models, as well as the newly developed Kong-Fang and Yan-Chen models. It pointed out the impact of high-pressure mechanical behavior of concrete and the cumulative effect of damage under hydrostatic pressure on the calculation results. Finally, a discussion was conducted on the inherent flaws, applicability, and research difficulties of local constitutive models of concrete in the finite element method. This provides a reference for the selection and research of constitutive models when conducting numerical analysis of the blast and impact resistance of concrete structures.</div></div>","PeriodicalId":50318,"journal":{"name":"International Journal of Impact Engineering","volume":"195 ","pages":"Article 105145"},"PeriodicalIF":5.1,"publicationDate":"2024-10-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142530986","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 : 2024-10-22DOI: 10.1016/j.ijimpeng.2024.105149
Lena Leicht , Matteo Colombo , Paolo Martinelli , Cesare Signorini , Viktor Mechtcherine , Marco di Prisco , Silke Scheerer , Manfred Curbach , Birgit Beckmann
This study compares the blast performance of reinforced concrete (RC) slabs with and without strengthening on the impact-facing side. The strengthening strategy employed the application of two thin layers of materials with a high mutual stiffness offset, i.e., high-contrast layers. The first is a low-strength, low-modulus damping layer made of infra-lightweight concrete, followed by a second layer of high-ductility fiber-reinforced concrete. The plain RC slabs under investigation vary in thickness of either 40 mm or 100 mm. The layered specimens consist of a 40 mm thick RC slab strengthened with a 40 mm damping layer and a 20 mm cover SHLC3 layer. This configuration enables a comparison of its behavior with the unstrengthened specimen (a plain 40 mm thick RC slab) and a specimen with a similar eigenfrequency (the plain 100 mm thick RC slab). The employed shock tube subjects the specimens to two rapidly rising areal pressures: a low-pressure wave reaching approximately 0.4 MPa and a high-pressure wave peaking at around 1.2 MPa. The study assesses the specimens’ response in terms of accelerations, velocities, and deformations. Additionally, it evaluates damage by analyzing crack patterns, Ultrasonic Pulse Velocity (UPV) measurements, and damping analysis. Overall, the layered specimens exhibited performance nearly equivalent to the 100 mm thick specimens, displaying similar deformations and velocities despite having lower mass and bending stiffness. The high-pressure shock wave hardly damaged the layered specimens, unlike the 40 mm thick slabs.
{"title":"Protective potential of high-contrast mineral-bonded layers on reinforced concrete slabs subjected to uniform shock waves","authors":"Lena Leicht , Matteo Colombo , Paolo Martinelli , Cesare Signorini , Viktor Mechtcherine , Marco di Prisco , Silke Scheerer , Manfred Curbach , Birgit Beckmann","doi":"10.1016/j.ijimpeng.2024.105149","DOIUrl":"10.1016/j.ijimpeng.2024.105149","url":null,"abstract":"<div><div>This study compares the blast performance of reinforced concrete (RC) slabs with and without strengthening on the impact-facing side. The strengthening strategy employed the application of two thin layers of materials with a high mutual stiffness offset, i.e., high-contrast layers. The first is a low-strength, low-modulus damping layer made of infra-lightweight concrete, followed by a second layer of high-ductility fiber-reinforced concrete. The plain RC slabs under investigation vary in thickness of either 40<!--> <!-->mm or 100<!--> <!-->mm. The layered specimens consist of a 40<!--> <!-->mm thick RC slab strengthened with a 40<!--> <!-->mm damping layer and a 20<!--> <!-->mm cover SHLC<sup>3</sup> layer. This configuration enables a comparison of its behavior with the unstrengthened specimen (a plain 40<!--> <!-->mm thick RC slab) and a specimen with a similar eigenfrequency (the plain 100<!--> <!-->mm thick RC slab). The employed shock tube subjects the specimens to two rapidly rising areal pressures: a low-pressure wave reaching approximately 0.4<!--> <!-->MPa and a high-pressure wave peaking at around 1.2<!--> <!-->MPa. The study assesses the specimens’ response in terms of accelerations, velocities, and deformations. Additionally, it evaluates damage by analyzing crack patterns, Ultrasonic Pulse Velocity (UPV) measurements, and damping analysis. Overall, the layered specimens exhibited performance nearly equivalent to the 100<!--> <!-->mm thick specimens, displaying similar deformations and velocities despite having lower mass and bending stiffness. The high-pressure shock wave hardly damaged the layered specimens, unlike the 40<!--> <!-->mm thick slabs.</div></div>","PeriodicalId":50318,"journal":{"name":"International Journal of Impact Engineering","volume":"196 ","pages":"Article 105149"},"PeriodicalIF":5.1,"publicationDate":"2024-10-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142593294","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}
To investigate dynamic fracture behavior in the metal, three metal spheres (e.g., steel sphere, high purity tungsten sphere, and high purity lead sphere) are accelerated by the gas gun devices to impact glass spheres under the critical speed range (i.e., from 70 m/s to 210 m/s). The velocity interferometer system for any reflector (VISAR) devices are employed to measure the particle velocities at the back surface of glass sphere, and high-speed photographs are utilized to capture the failure process at the metal-glass interface. Due to the asynchronous evolutions of stress fields and strain fields in the violent failure process, the results illustrate quite different failure mechanisms from those by the Split Hopkinson Pressure Bar (SHPB) impacting. Fragmentations of the glass sphere are caused mainly by the radial cracks and the lateral cracks around the metal-glass interface and the edges of the sphere with increasing impact velocity. Dynamic failures in the three metal impactors exhibit different modes, e.g., tensile fracture in the steel impactor, shear fracture in the tungsten impactor, and compressed yielding in the lead impactor. The transferring of strain energy releasing is introduced to describe the failure behavior at the metal-glass interface, and a relaxation-diffusion equation of strain energy releasing is then established based on the experimental results and the numeric results by the discrete element method (DEM). The evolutions of failures at the metal-glass interface are discussed. Further investigation is conducted to describe the dynamic fractures in tungsten impactors and steel impactors based on the dimensional analyses, and the quantitative expressions of these strain rate dependent fracture strains and crack width in the metal impactors are obtained. The results are helpful for the profound understanding of the dynamic fracture in the metal structures and the dynamic fragmentations in the brittle material when subjected to impact loading.
{"title":"Dynamic failures at the metal-glass interface under impact loading","authors":"Haifeng Yang, Songlin Xu, Liangzhu Yuan, Meiduo Chen, Yushan Xie, Pengfei Wang","doi":"10.1016/j.ijimpeng.2024.105136","DOIUrl":"10.1016/j.ijimpeng.2024.105136","url":null,"abstract":"<div><div>To investigate dynamic fracture behavior in the metal, three metal spheres (e.g., steel sphere, high purity tungsten sphere, and high purity lead sphere) are accelerated by the gas gun devices to impact glass spheres under the critical speed range (i.e., from 70 m/s to 210 m/s). The velocity interferometer system for any reflector (VISAR) devices are employed to measure the particle velocities at the back surface of glass sphere, and high-speed photographs are utilized to capture the failure process at the metal-glass interface. Due to the asynchronous evolutions of stress fields and strain fields in the violent failure process, the results illustrate quite different failure mechanisms from those by the Split Hopkinson Pressure Bar (SHPB) impacting. Fragmentations of the glass sphere are caused mainly by the radial cracks and the lateral cracks around the metal-glass interface and the edges of the sphere with increasing impact velocity. Dynamic failures in the three metal impactors exhibit different modes, e.g., tensile fracture in the steel impactor, shear fracture in the tungsten impactor, and compressed yielding in the lead impactor. The transferring of strain energy releasing is introduced to describe the failure behavior at the metal-glass interface, and a relaxation-diffusion equation of strain energy releasing is then established based on the experimental results and the numeric results by the discrete element method (DEM). The evolutions of failures at the metal-glass interface are discussed. Further investigation is conducted to describe the dynamic fractures in tungsten impactors and steel impactors based on the dimensional analyses, and the quantitative expressions of these strain rate dependent fracture strains and crack width in the metal impactors are obtained. The results are helpful for the profound understanding of the dynamic fracture in the metal structures and the dynamic fragmentations in the brittle material when subjected to impact loading.</div></div>","PeriodicalId":50318,"journal":{"name":"International Journal of Impact Engineering","volume":"195 ","pages":"Article 105136"},"PeriodicalIF":5.1,"publicationDate":"2024-10-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142530988","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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