International Journal of Impact Engineering最新文献

{"title":"Mechanical response and failure mechanism of circular inclusion embedded in brittle materials under dynamic impact","authors":"","doi":"10.1016/j.ijimpeng.2024.105088","DOIUrl":"10.1016/j.ijimpeng.2024.105088","url":null,"abstract":"<div><p>Inclusions are prevalent in both natural and synthetic materials. Gaining a comprehensive understanding of their dynamic response and interaction with the surrounding matrix is essential in fundamental mechanics and engineering applications. This study aims to achieve such understanding through theoretical analysis, experimental investigations, and numerical simulations, focusing on the dynamic destruction of inclusions and the underlying mechanisms. Firstly, the circumferential, radial, and shear stresses around elastic heterogeneous inclusions were derived by the wave function expansion and Duhamel integration methods. Subsequently, a set of experiments on sandstone specimens containing three types of inclusions (plaster, epoxy resin, cement) were conducted utilizing the Split Hopkinson Pressure Bar (SHPB) system in conjunction with high-speed photography and Digital Image Correlation (DIC) techniques to obtain the surface deformation of inclusion specimens. Eventually, a series of Finite Element Method (FEM) numerical simulations adopted suitable materials were also carried out to investigate the fracture process of inclusion and matrix under dynamic impact. The results demonstrate that the stress distributions and fracture mode of matrix and inclusion are highly dependent on the physical and mechanical properties of the inclusions and the surrounding matrix, specifically, density <em>ρ</em>, elastic modulus <em>E</em>, Poisson's ratio <em>v</em>, and strength. With an increase in the <em>E</em> and <em>v</em>, there is a reduction in the concentration of circumferential stress, while the radial and shear stresses experience an increase. The experimental and numerical results corroborated the theoretical findings and indicated that the localized dynamic stress concentrations induced by wave scattering around the inclusions directly dominated both local and overall specimen failure. Due to the dissimilarities in elastic parameters and strength between the inclusion and the matrix, the stress state of the inclusion and the interface is not homogeneous. Under dynamic loading, the weaker inclusion experiences tensile cracking at both ends of the loading, and as the mechanical properties (<em>ρ,</em> E, <em>v</em>, and strength) of the inclusion rise, a transition from tensile- hybrid-shear failure occurs within the inclusion. The findings of this study help us understand the dynamic failure mechanisms of dissimilar inclusions in brittle material.</p></div>","PeriodicalId":50318,"journal":{"name":"International Journal of Impact Engineering","volume":null,"pages":null},"PeriodicalIF":5.1,"publicationDate":"2024-08-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142044761","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":"On the strain rate-dependent mechanical behavior of PE separator for lithium-ion batteries","authors":"","doi":"10.1016/j.ijimpeng.2024.105079","DOIUrl":"10.1016/j.ijimpeng.2024.105079","url":null,"abstract":"<div><p>The separator is a critical component for ensuring electrochemical cycling performance and preventing internal short circuits in lithium-ion batteries. For the collision safety of lithium-ion batteries, understanding the rate-dependent mechanical behavior of the separator is essential for battery impact modeling and safety prediction. This study conducts a comprehensive experimental investigation into the strain rate–dependent tensile/compressive behavior and failure mechanism of the polyethylene (PE) separator under quasi-static and dynamic conditions. The combination of deformation images recorded by cameras and post-mortem characterization using SEM was employed to clarify the rate-dependent deformation and fracture mechanism of the separator under both tensile and compressive loading. The experimental results demonstrate a significant strain rate effect on the tensile/compressive mechanical properties and damage/failure behavior of the separator. Furthermore, the effect of the strain rate on the mechanical properties, including the tensile strength, tensile fracture strain, tensile elastic modulus, compressive modulus, yield stress and yield strain of separator, was analyzed and discussed. A significant strain rate-dependent tensile damage and fracture behavior of the separator was observed, where the fracture site exhibited an obvious phase transition and skeletal lamella fracture under extremely high strain rate tensile loading. The separator underwent severe damage under dynamic compressive conditions. The results of this study provide an important basis for the establishment of rate-dependent safety criterion and short circuit prediction of lithium-ion batteries under impact loading, and shed light on understanding separator failure-induced short circuit issues in battery collision safety scenarios.</p></div>","PeriodicalId":50318,"journal":{"name":"International Journal of Impact Engineering","volume":null,"pages":null},"PeriodicalIF":5.1,"publicationDate":"2024-08-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142040577","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":"Design, simulation and experiment study of a snap-fit spatial self-locking system for energy absorption","authors":"","doi":"10.1016/j.ijimpeng.2024.105076","DOIUrl":"10.1016/j.ijimpeng.2024.105076","url":null,"abstract":"<div><p>Due to the strong destructiveness and poor predictability of the impact loading, energy absorption structures are easy to cause secondary damage in emergency situations. The proposed self-locking system for energy absorption can effectively solve this problem, but also can realize fast installation, disassembly and free editing. In this paper, a new snap-fit spatial self-locking energy absorption system is designed according to the self-locking idea of mortise and tenon structure. Firstly, the effects of concentrated loading, uniform distributed loading and friction properties on the self-locking characteristics under nine different spatial directions are studied by finite element simulation. Then, the crushing mechanism is revealed by impact experiment, and the performance and engineering adaptability of the existing self-locking energy absorption systems are compared. Finally, the design criteria for the system is derived. The results show that the system will not fly away under the impact loading in any spatial direction, and has good self-locking characteristics, while the friction properties have little effect on the self-locking characteristics of the system. In addition, under the uniform distributed loading, the deformation mode is the most regular in the direction 3, and the specific energy absorption in the direction 9 is as high as 7.07 J/g. Furthermore, when the total number of the structural unit in the self-locking energy absorption system is not less than twelve, the total energy absorption is linear with the number of layers, width and total number of the structural unit. Consequently, this study provides a new research idea for the design and feasibility of the self-locking energy absorption system.</p></div>","PeriodicalId":50318,"journal":{"name":"International Journal of Impact Engineering","volume":null,"pages":null},"PeriodicalIF":5.1,"publicationDate":"2024-08-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142048672","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":"Blast resistance of multi-compartment structure subjected to the contact underwater explosion","authors":"","doi":"10.1016/j.ijimpeng.2024.105081","DOIUrl":"10.1016/j.ijimpeng.2024.105081","url":null,"abstract":"<div><p>In this paper, the underwater blast behavior of a multi-compartment protective system was numerically analyzed using AUTODYN. A group of structures composed of three circular metal plates and two cylindrical compartments in between were subjected to a contact underwater explosion (UNDEX). An experimental study was carried out to validate the numerical simulation model. Besides, a rigorous parametric study was conducted on structural geometry and its material variables using the full-factorial and response surface methods in DoE software. Later on, a multi-objective optimization was carried out on the obtained objective functions for the prediction of the Central Deflection of the backplate <span><math><mrow><mo>(</mo><mrow><mi>C</mi><mi>e</mi><mi>n</mi><mi>t</mi><mi>D</mi></mrow><mo>)</mo></mrow></math></span> and Energy Absorption per Areal Mass <span><math><mrow><mo>(</mo><mrow><mi>E</mi><mi>A</mi><mi>p</mi><mi>M</mi></mrow><mo>)</mo></mrow></math></span>. The proposed optimal condition was also validated using the numerical simulation model. It was found that using the arrangement of Al2024-T3, St37, and St37 as the faceplate, midplate, and backplate in a configuration as well as mediums of water and air in-between outperforms in terms of minimum <span><math><mrow><mi>C</mi><mi>e</mi><mi>n</mi><mi>t</mi><mi>D</mi></mrow></math></span> and maximum <span><math><mrow><mi>E</mi><mi>A</mi><mi>p</mi><mi>M</mi></mrow></math></span>. Using the same mediums in compartments regardless of type of layers leads to backplate tearing and structure failure. From the structural geometry point of view, it was found that variations of midplate thickness and fore compartment height have the most influence on <span><math><mrow><mi>C</mi><mi>e</mi><mi>n</mi><mi>t</mi><mi>D</mi></mrow></math></span> and <span><math><mrow><mi>E</mi><mi>A</mi><mi>p</mi><mi>M</mi></mrow></math></span>, respectively. Therefore, the suggested configuration can be successfully used as a marine armor with dimensional considerations under contact underwater explosion.</p></div>","PeriodicalId":50318,"journal":{"name":"International Journal of Impact Engineering","volume":null,"pages":null},"PeriodicalIF":5.1,"publicationDate":"2024-08-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142040588","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":"Rigid–flexible coupling design and reusable impact mitigation of the hierarchical-bistable hybrid metamaterials","authors":"","doi":"10.1016/j.ijimpeng.2024.105075","DOIUrl":"10.1016/j.ijimpeng.2024.105075","url":null,"abstract":"<div><p>Mechanical metamaterials with multistable unit cells featured by negative stiffness or quasi-zero stiffness is attracting increasing attention owing to their unique mechanical properties and reusable potential. In this paper, a hierarchical-bistable hybrid metamaterial with rigid–flexible coupling design is proposed, demonstrating excellent mitigation performance and protection against multiple impacts. The metamaterial consists of a multi-layer bistable beams with a central honeycomb and is manufactured by 3D printing. Firstly, the negative stiffness characteristics of the curved beams in the metamaterial are theoretically determined, and the convergence of the finite element model under different mesh sizes is analyzed. And the quasi-zero stiffness characteristics of the metamaterial have been confirmed, along with its more stable and uniform deformation pattern, through the quasi-static compression experiment. Then the buffering performance of the metamaterial is studied in ball impact tests, showing an average improvement of about 65% compared to the rigid control group, while verifying the accuracy of the finite element model. With the analysis of the deformation modes and strain energy, the mitigation mechanism of metamaterials is demonstrated to extend the contact time and disperse the impact load through the layered deformation to reduce the peak response, instead of relying on plastic strain. Finally, the reusability of the metamaterial is explored by the ten-times plate impacts simulation. The results demonstrate that the metamaterial decreases the plastic strain of its structure by 60% while reducing impact response, thereby preventing the premature failure of core components. These results demonstrate the great potential of the proposed metamaterials for various engineering applications, including aircraft or spacecraft landing protection, vehicle pedestrian protection, and the transportation protection of fragile objects or precision instruments.</p></div>","PeriodicalId":50318,"journal":{"name":"International Journal of Impact Engineering","volume":null,"pages":null},"PeriodicalIF":5.1,"publicationDate":"2024-08-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141992840","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":"Damage quantification based on drift ratios and axial capacity degradation for RC columns under low-velocity impact loads","authors":"","doi":"10.1016/j.ijimpeng.2024.105078","DOIUrl":"10.1016/j.ijimpeng.2024.105078","url":null,"abstract":"<div><p>Damage determination and quantification are critical issues in conducting damage assessment and performance-based design for RC columns under low-velocity impact loads. An impediment in these issues lies in defining reasonable damage criteria. To this end, a framework inspired by existing experimental results is proposed to quantify the damage of RC columns. The core concept of this framework is to establish the relationship between the engineering demand parameter (i.e., drift ratio) and the damage index based on residual axial capacity and to convert the damage index threshold to the drift ratio threshold using a reliability-based method. According to the proposed framework, damage criteria are developed for RC columns in two typical impact scenarios, including the mid-span and near-base impacts. During this process, linear relationships between the maximum drift and the residual one at the impact location are developed by statistically analyzing the existing experimental data (a total of 212 test samples). Based on experimentally validated numerical models, empirical formulas for estimating the residual axial capacity of RC columns are established. The maximum drift, the residual drift, and the axial capacity degradation are interrelated in the proposed damage criteria, overcoming the limitation that the current deformation-based damage criteria used for low-velocity impact loads lack physical significance.</p></div>","PeriodicalId":50318,"journal":{"name":"International Journal of Impact Engineering","volume":null,"pages":null},"PeriodicalIF":5.1,"publicationDate":"2024-08-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142007118","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":"Evaluation of the mechanical shock testing standards for electric vehicle batteries","authors":"","doi":"10.1016/j.ijimpeng.2024.105077","DOIUrl":"10.1016/j.ijimpeng.2024.105077","url":null,"abstract":"<div><p>The safety of Li-ion batteries (LIB) has become an important issue with the continuously increased use of electric vehicles (EV) in the world. In a survivable vehicle crash, when the vehicle needs to maintain structural integrity, crash-induced shock may damage EV's LIB. Therefore, an evaluation of commonly used mechanical shock test standards for EV battery module and pack is performed in this study against the crash-induced shock signals collected from National Highway Traffic Safety Administration (NHTSA) New Car Assessment Program (NCAP) tests. Various shock analysis methods including signal characteristics in time domain, power spectral density (PSD) and shock response spectrum (SRS) in frequency domain, and the acceleration/velocity-change diagram are used for the evaluation. It is found that most peak accelerations of NCAP shock signals significantly exceed the peak accelerations specified in shock testing standards. Crash-induced shocks cannot be fully represented by the half-sine pulse adopted in shock testing standards. In both time and frequency domains, the existing shock testing standards generally underestimate the severities of the crash-induced shocks, and therefore, are non-conservative. It also shows that the correct selection of a filter for the processing of the original crash-induced shock signal is crucial for the specification of EV battery shock environment and shock response analyses. The results obtained in this research can support the development of more reliable shock testing standards for EV batteries.</p></div>","PeriodicalId":50318,"journal":{"name":"International Journal of Impact Engineering","volume":null,"pages":null},"PeriodicalIF":5.1,"publicationDate":"2024-08-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.sciencedirect.com/science/article/pii/S0734743X2400201X/pdfft?md5=05e40da0d262787982512788fcc0af35&pid=1-s2.0-S0734743X2400201X-main.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142007117","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":"Experimental and analytical investigations on single and repetitive impact failure responses of composite sandwich panels with orthogonal woven GFRP facesheets and PVC foam cores","authors":"","doi":"10.1016/j.ijimpeng.2024.105064","DOIUrl":"10.1016/j.ijimpeng.2024.105064","url":null,"abstract":"<div><p>Due to the unique design requirements for high load-bearing capacity of ship structures, composite materials used in the marine industry are gradually being developed with the characteristics of multi-layer sandwich structures with large thickness and cross-section, which are different from thin-walled composite materials widely applied in the aeronautical industry. However, sandwich composite materials used in marine structures have high susceptibility to impact event during in-service applications. The impact induced damage may seriously affect their mechanical performance and structural safety. Therefore, a comprehensive investigation in this paper on the failure mechanisms of composite sandwich panels with orthogonal woven GFRP facesheets and a PVC foam core layer is carried out with a series of single and repetitive low-velocity impact tests. The variations of impact force, dent depth, structural stiffness, failure modes, energy absorption and so on of composite sandwich panels against impact energy levels and impact numbers were explored. The results demonstrate that the delamination damage threshold at the first impact, the sudden drop of peak force and the slow descent process of impact force are the three typical characteristics of impact responses that corresponded to delamination initiation and fibre breakage of the upper panel, and compression damage of the core layer, respectively. The accumulated impact-induced damage has a significant negative effect on load-bearing and energy-absorption capabilities of composite sandwich panels. Moreover, an approximate theoretical analytical method is presented to solve the impact resistance of composite sandwich panels. The analytical results are compared well with experimental results. This research provides a detailed understanding of the damage mechanisms of composite sandwich panels under impact loadings and a guidance for impact resistant design of ship protective structures.</p></div>","PeriodicalId":50318,"journal":{"name":"International Journal of Impact Engineering","volume":null,"pages":null},"PeriodicalIF":5.1,"publicationDate":"2024-08-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141978219","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Experimental study of damage modes of RC and RCS walls under combined loading of fragments and shock waves","authors":"","doi":"10.1016/j.ijimpeng.2024.105065","DOIUrl":"10.1016/j.ijimpeng.2024.105065","url":null,"abstract":"<div><p>A pressing issue for reinforced concrete walls, which are commonly used as building structures, is how the fragments and shock waves generated by the explosion of a cased charge affect the concrete structure. In this paper, the damage modes of reinforced concrete walls (RC walls) and reinforced concrete-steel composite walls (RCS walls) under the combined loading of fragments and shock waves are investigated by experimental methods, and the effects of wall thickness, strength, stand-off distance, and thickness of the steel plate on the back on the damage modes of the walls are discussed. Based on the experimental data, the damage modes of the walls were classified into three classes. In comparison, the installation of steel plates on the back of concrete walls was found to be a significant means of protection, effectively preventing the penetration of metal fragments and the splashing of concrete fragments.</p></div>","PeriodicalId":50318,"journal":{"name":"International Journal of Impact Engineering","volume":null,"pages":null},"PeriodicalIF":5.1,"publicationDate":"2024-08-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141953841","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":"Structural evaluation of scaled double-layered containment structure against rigid missile impact","authors":"","doi":"10.1016/j.ijimpeng.2024.105063","DOIUrl":"10.1016/j.ijimpeng.2024.105063","url":null,"abstract":"<div><p>In this experimental study, the scaled double-layer containment structure represented by 1000 mm × 1000 mm targets of outer reinforced and inner prestressed concrete of thickness 200 mm has been subjected to ballistic impact by 10 and 20 kg rigid missiles at incidence velocities, close to 100 m/s. The inner layer of prestressed concrete was cast with and without a monolithic rear steel liner of thickness 1.5 mm. The prestressing force was induced in the vertical and horizontal directions with respect to 15 % of the characteristic compressive strength of concrete (M45). In double-layer tests, the 20 kg missiles perforated the outer layer target with significant residual velocities, while the 10 kg missile just perforated the outer layer. The 20 kg missile, when impacted the inner layer prestressed concrete target with a rear steel liner, experienced no damage. However, when impacted, the prestressed concrete target without a rear steel liner suffered significant rear surface cracking but no scabbing of concrete. This concludes that steel liner plays a substantial role in mitigating rear surface cracking and minimizing damage to the inner layer target. The ballistic tests were also performed on single independent prestressed concrete targets with and without steel liner against 20 kg missiles. In single-layer tests, the target with the rear surface steel liner restricted the perforation phenomena, however, significant damage occurred to the concrete and the steel liner. On the other hand, the target without a steel liner underwent complete failure through perforation. Hence, steel liners not only controlled the rear surface cracking (in double-layer) but also effectively controlled the perforation phenomena (in single-layer). No loss of prestressing force was observed in the case of the double-layered configuration, however, when the missile impacted the single-layered prestressed concrete target, a noticeable loss of prestressing force was observed. The perforation limit velocities calculated using Modified NDRC, BRL-NDRC, CEA-EDF, UMIST, and Modified UMIST empirical models for reinforced and prestressed concrete targets were compared with the experimental results.</p></div>","PeriodicalId":50318,"journal":{"name":"International Journal of Impact Engineering","volume":null,"pages":null},"PeriodicalIF":5.1,"publicationDate":"2024-07-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142044762","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}