Failure Moment Research Articles

Lateral-Torsional Failure and DSM Design of CFS Lipped Channel Beams at Room and Elevated Temperatures

About a decade ago, in-depth investigations on the behaviour of cold-formed steel (CFS) single-span simply supported lipped channel beams failing in lateral-torsional modes at both room and elevated temperatures were reported at QUT (Queensland Technical University). They revealed a significant underestimation of the lateral-torsional (LT) failure moments by the Direct Strength Method (DSM) global design curve at room temperature, then codified in the Australian/New Zealand and North American specifications. In order to remedy this situation, these authors proposed two novel DSM-based beam strength curve sets, which were found to substantially improve the LT failure moment prediction quality, both at room and elevated temperatures. This work aims at extending the scope of the above investigations, by analysing a visibly larger set of CFS lipped channel beams at elevated temperatures (up to 800 °C), exhibiting (i) various cross-section dimensions and yield stresses, selected to cover wider LT slenderness ranges, (ii) two end support conditions, differing only in the end cross-section wall displacement/rotation and warping restraints (either fully free or fully prevented), and (iii) temperature-dependent steel material properties according with the model prescribed in Part 1-2 of Eurocode 3. The results presented and discussed consist of beam LT post-buckling equilibrium paths and failure moments, obtained through Abaqus shell finite element GMNIA that include critical-mode (LT) initial geometrical imperfections. Lastly, the numerical failure moment data obtained in this work and reported in the literature are used to develop and propose a new unified set of DSM-based strength curves capable of adequately handling beam LT failures at room or elevated temperatures. Since it is shown that the proposed strength curve set provides a quite good LT failure moment prediction quality, it is fair to argue that it constitutes a good starting point to search for an efficient general DSM-based design approach for CFS beams failing in LT modes at room and elevated temperatures.

Co-Construction of Iteration Through Failure Moments: Interactions Between Museum Educators and Visitors

Museum educators play a major role in how visitors’ experience failure moments during STEM-related activities. The purpose of this study was to explore how museum educators co-constructed iteration through failure moments with visitors during an engineering activity. Utilizing an instrumental case study, we analyzed video data and one-on-one reflective meetings from five museum educators. Through our analysis, we highlight how educators and visitors are able to jointly attend, interpret, and respond to failures that leads to continuous improvements of the prototype and/or design process (i.e., iteration). The significance of this study lies in providing informal educators with approaches they can incorporate to support visitors during the failure-learning process, namely, strategies that develop visitors’ noticing skills around failure.

Analysis of acoustic emission signal in the tensile process of weld-bonding joint and its damage model

ABSTRACT This paper analysed the acoustic emission signals acquired during the tensile test of DP780 weld-bonding joints, and the Gaussian equation was used to fit the cumulative hits and the load to establish relevant damage models. The process parameters were designed based on the Box-Behnken Design method, and the wavelet packet was used to decompose the collected AE signals. The results showed that, in the elastic stage, no AE signal emitted, and the AE signal was mainly concentrated in the plastic stage, the hardening stage and the failure moment of the weld nugget or the adhesive layer. At the failure instant of the adhesive layer or the weld nugget, the signal amplitude was the largest, and the failure frequency was mainly concentrated in the middle and low-frequency bands. The failure of the adhesive layer and the weld nugget could be distinguished from the energy distribution diagrams, and the established damage model could reflect the damage state of the specimen. The results proved that the acoustic emission technique can provide support for the non-destructive testing of the weld-bonding joint.

Cracking performance in the hogging moment region of HSS-UHPC continuous composite girder bridges

To elucidate the cracking performance of concrete slabs at the negative bending moment region of high strength steel (HSS)-ultra high performance concrete (UHPC) continuous composite girder bridges, eight scale-reduced steel-concrete composite beams, constructed using HSS and UHPC that varying parameters of UHPC slab thickness and width and shear connection degree at the steel-concrete interface were prepared and tested. The composite beams' cracking pattern, bending stiffness, load-deflection curve, steel-concrete interfacial slippage, and strain history were presented and discussed. The test results show that the HSS-UHPC composite beams subjected to negative bending moments exhibited favorable cracking performance. With the UHPC slab width increasing from 450 mm to 550 mm, the composite beams' initial cracking moment, bending stiffness, and flexural ductility increased by 33.4%, 20.5%, and 39.8%, respectively. The utilization of a thick UHPC slab benefited the performance of the composite beams under negative bending moments. Replacing the 80 mm-thick slab with a 110 mm-thick slab improved the structure’s cracking moment and bending stiffness by 15.0% and 21.4%, respectively. Additionally, as the shear connection degree increases from 0.64 to 1.02, the initial cracking and ultimate failure moments of the composite beam were improved by 7.2% and 1.6%, respectively. In contrast, the bending stiffness of the beams with a shear connection degree of 1.02 was 12.4% smaller than those of 0.64. A comprehensive comparison between the formula-predicted cracking performance and current experimental results was performed to examine the capability of existing design approaches in calculating the HSS-UHPC composite beams. The flexural resistance algorithm proffered by Xu exhibits favorable alignment with test results, thereby providing a compelling methodology for designing HSS-UHPC continuous composite girder bridges.

Identifying and shifting educators' failure pedagogical mindsets through reflective practices.

In this paper, we add to the scant literature base on learning from failures with a particular focus on understanding educators' shifting mindset in making-centred learning environments. The aim of Study 1 was to explore educators' beliefs about failure for learning and instructional practices within their local making-centred learning environments. The aim of Study 2 was to examine how participation in a video-based professional development cycle regarding failure moments in making-centred learning environments might have shifted museum educators' failure pedagogical mindsets. In Study 1, the sample included 15 educators at either a middle school or museum. In Study 2, the sample included 39 educators across six museums. In Study 1, educators engaged in a semi-structured interview that lasted between 45 and 75 min. In Study 2, the six museums video recorded professional development sessions. Results from Study 1 highlighted educators' failure pedagogical mindsets as either underdeveloped or rigid and absent of relational thinking between self- and youth-failures. One key result from Study 2 was a shift from an abstract sense of failure as youth-focused to a practical sense of failure as educator-focused and/or relational (i.e., youth educator-focused failure moments). Based on the results from Study 1 and Study 2, our research suggests that exploring an educator's relationship with failure is important and witnessing and reflecting upon their own failure pedagogical mindset in action may facilitate a shift towards a more complex and interconnected space for growth and development of both educators and youth.

CFS lipped channel beams buckling in distortional modes at elevated temperatures: Behaviour, failure and DSM design

This work reports the findings of a comprehensive numerical investigation on the post-buckling behaviour, failure and Direct Strength Method (DSM) design of cold-formed steel (CFS) single-span simply supported lipped channel beams buckling in distortional modes at elevated temperatures (up to 800 °C) due to fire conditions. It extends the scope of a previous investigation carried out by Landesmann and Camotim [1], by analysing a substantially larger lipped channel beam set, exhibiting various cross-section dimensions and yield stresses, selected to cover wider distortional slenderness ranges. As done before, (i) the beams analysed display two end support conditions, (ii) the Eurocode 3 (part 1.2) model to describe the temperature-dependence of the CFS material properties is adopted and (iii) the results are obtained by means of Abaqus shell finite element GMNIA. After presenting and discussing the main features of the beam distortional post-buckling behaviour, extensive beam failure moment sets are gathered and used to develop and validate DSM-based design approaches. The methodology followed consists of modifying the most performant available DSM-based design curves (developed for beams at ambient temperature [2]), which naturally involves the temperature-dependant reduction factors of the CFS model. A merit assessment procedure shows that the modified DSM-based strength curves predict the lipped channel beam distortional failure moments with remarkable accuracy and reliability, thus constituting an excellent starting point to search for a DSM-based design approach capable of handling arbitrary CFS beams failing in distortional modes at elevated temperatures.

Research on acoustic emission multi-parameter characteristics in the failure process of imitation steel fiber reinforced concrete

Studies of the damage process of fiber-reinforced concrete through acoustic emission are very significant for concrete structural health monitoring. In this study, three specifications of fiber concrete and one group of plain concrete were prepared to carry out the uniaxial compression test and acoustic emission monitoring test; then, b value, entropy H, and variance D, were calculated and compared their characterization effect. The main results showed that fibers increased the degree of internal inhomogeneity of the specimens, making the acoustic emission response more active. For every 2% increase in fiber content, the total acoustic emission count and energy increased by about 20%, the acoustic emission precursor parameters changed more significantly, the b-value decreased by 2%–10%, the entropy and variance increased by 3%–5% and 2%–22%, respectively. The variation of b value, entropy, and variance can be divided into three phases: initial rising/falling, unstable transition, and fluctuating slow-rising/falling, which had good consistency with the stress curve. According to the linear fitting results, the b value that dropped below the envelope in the post-peak phase can be taken as the damage precursor point, and its accuracy and generalizability were better. The entropy at the failure moment was around 0.6, but the value close to or above 0.6 occurred several times during the damage process, and taking the entropy value beyond the envelope range as the failure precursor point may lead to the error early warning. The variance was slightly worse to distinguish small-scale fracture, but was not susceptible to high-energy events. Therefore, variances close to 5 or beyond the envelope interval can be regarded as the precursor of final failure. As for studying concrete damage processes with acoustic emission, it is suggested to combine multiple parameters for comprehensive discrimination.

Damage evaluation and failure mechanism analysis of axially compressed circular concrete-filled steel tubular column via AE monitoring

Concrete-filled steel tubular (CFST) columns are frequently used as the main load-bearing components in engineering structures due to their excellent load-bearing capacity. However, the presence of steel tube makes it impossible to accurately detect the damage characteristics of concrete by only relying on traditional mechanical measurement methods. This article quantitatively investigates the concrete damage of circular CFST column during axial compression based on the acoustic emission (AE) technique. Through the cumulative AE parameters including amplitude, count, and energy, the axial compression process of the CFST column can be divided into five main stages (Stage I is divided into two substages) to represent the different damage degree. The damage characteristics of concrete at each stage were explained by combining AE results and mechanical phenomena. A sensitivity analysis of the axial compression process was carried out using the Historic Index (HI) and Severity (Sr) and found that the sudden rise in HI and Sr corresponded to the changes in the different loading stages. The Improved b (Ib) value analysis calculated from the AE amplitudes reflects the evolution mechanism of the crack and can be used for the identification of the final failure moment of the specimen. Finally, a new method for processing and analyzing AE parameters was proposed, which effectively enhanced the dimensionality of real-time monitoring information on the damage of concrete filled in the steel tube.

Web slenderness effects on flexure of compound normal and high-strength steel beams

This paper discusses web slenderness effects on the flexural behaviour of epoxy adhesive-bonded compound normal and high-strength steel beams. The compound beams were simply supported and consisted of an I-section connected, on its top flange, to a channel section using an epoxy adhesive. A non-linear three-dimensional finite-element modelling study was performed using Abaqus software for the analysis of the beams. The non-linear finite-element modelling was verified against tests on compound steel beams with different cross-sections. An extensive parametric study was carried out using the finite-element modelling to study the effects of the change in web slenderness, cross-sectional geometries, beam lengths and steel strengths on the flexural behaviour of compound steel beams. The failure moments predicted by the finite-element modelling were compared with the design moments predicted by the European code for steel beams in flexure. It is shown that the code generally overestimated the design failure moments for most of the epoxy adhesive-bonded compound steel beams investigated in this study. In addition, reliability analysis was performed to assess the reliability of the design rules of the code. Generally, it was found that the European code is unconservative and statistically unreliable for the epoxy adhesive-bonded compound beams investigated in this study.

Axial compressive performances of stiffened composite panels: Experimental and numerical study

Axial compressive performances of stiffened composite panel were studied in this manuscript. In experimental study, buckling phenomenon of three specimens appear at 413kN, 403kN and 403kN respectively while catastrophic failure appears at 964kN, 934kN and 970kN respectively. Thus average failure load is 2.35 times average buckling load, which indicate the large postbuckling capacity. Only local buckling appears in skin bay without buckling in stiffeners. Buckling strain and failure strain were proposed by the average value of several typical position strains at buckling and failure moment respectively. Average failure strain is −6483 με, which is 2.75 times buckling strain (-2354 με). The relationship between buckling and failure strain is similar to that of buckling and failure load. Failure modes contain debonding and fracture of stiffeners, the splitting and wrapped skin. In numerical study, finite element model considering the Hashin damage, cohesive element and geometry imperfection were built. Buckling load and failure load by FE results have −1.2% and −3.9% error compared to experimental ones, indicating the FE results have good accuracy. FE results show that debonding initiation is close to the moment of final catastrophic failure, about 92.7% failure load. Moreover, debonding area percentage have an accelerating increase trend with the compressive load increasing.

Evaluating the Lifetime of Quarto Stand Rolls on the Basis of the Contact Fatigue Criterion

One of the principal failures of the supporting and working rolls on the Quarto rolling system is the spalling of their surfaces due to the gradual accumulation of defects in contact volumes of a material. Nowadays to prevent such kind of degradation failures it is necessary to check out the stationary condition of the contact strength, which doesn’t answer to the question of the duration of the roll staying in the working state, i.e., its resource (lifetime). In the article a new physical-analytical model of the roll’s failure is suggested by the criterion of the surface layer fracture and the corresponding methodology of the expected resource calculation. The approach is based on the kinetic concept of damage of solid bodies, the energy (thermodynamic) condition of fracture of solid bodies and the fundamentals of reliability forecasting for technical objects. The feature of the suggested methodology is that the definition of the failure moment for the supporting or working rolls of the Quarto system derived from the condition of the current density of defects in surface layer of a material reaching the critical value, which is the function of the enthalpy of a material melting..

Devices operability control through gas supply system mode parameter routine measurement history

Effective control of pipeline systems requires adequate mathematical models. To match an object with the model it is necessary to analyze data on physical system structure and parameters and on operating processes (or the fluid flow regimes). Operating parameter measurements serve as data source for operational control. Incorrect SCADA readings bring about erroneous simulation results and unfounded dispatch decisions. Sometimes it is rather easy to identify information system failures and tell the cause. But sometimes as in the case of stage-by-stage failure such as sensor drift failure identification becomes really difficult. To detect and eliminate a progressive defect it is advisable to use maximum of available data, that is all measurements of the operating parameters (pressure, flow rate and, possibly, temperature) transmitted during the last few SCADA sessions. This approach takes into account the interdependence of operating parameters within the same session as well as specific parameter measurements during a number of sessions. The suggested model of identifying the failed device and the failure moment is built on a stochastic basis. The measurement results are considered random variables, which distribution obeys error theory standard assumptions.

Stability of Postcritical Deformation of CFRP under Static ±45° Tension with Vibrations.

The paper presents an experimental study on regularities of postcritical deformation of carbon-fiber-reinforced plastic (CFRP) under static ±45° tension. The employed test method is based on ASTM D3518. Displacement and strain fields were identified by a digital image correlation method (DIC) using a VIC-3D contactless optical video system. Acoustic emission signals were obtained using an AMSY-6 system. The surface analysis of samples was carried out using a CarlZeiss SteREO Discovery. V12 optical stereomicroscope and a DinoLite microscope. Three experimental test types were considered: active loading, deformation with unloadings, and tension under additional torsion vibrations with various amplitudes. Loading diagrams were constructed; they showed a number of stages in the damage accumulation process. It was analyzed how heterogeneous strain fields develop; a neck development during softening process was observed. It was noted that the loading system rigidity influences the failure moment. The research considered various shear strain calculation methods using a "virtual extensometer" instrument. Composite mechanical properties were obtained. A shear modulus reduction during a plastic strain increase was revealed. The acoustic emission signals were analyzed; three characteristic frequency bands were observed. Most of the contribution to cumulative energy was made by matrix cracking. A reduction of the number of AE signals associated with the violation of adhesion between the fibers and the matrix during postcritical deformation was observed. The research identified basic surface defects. An appearance of the defects corresponds with their identification by the AE system. It was revealed that the presence of additional torsion vibration leads to an increase in the softening stage length. It was concluded that due regard for the postcritical deformation stage and the loading system rigidity is reasonable during the structure strength analysis.

Local‐distortional interaction in cold‐formed steel lipped channel beams: Experimental investigation

AbstractNominee Professor Eduardo de Arantes e Oliveira Award 2021This paper reports an experimental investigation on the behaviour and strength of cold‐formed high‐strength steel (G450–G500) lipped channel beams susceptible to local–distortional interaction. The experimental campaign comprised 36 tests involving simply supported beams bent about the major axis, exhibiting various ratios between their distortional and local critical buckling moments (from 1.09 to 1.46) and acted by either uniform (20 tests) or non‐uniform (trapezoidal: 16 tests) bending diagrams. The results presented and discussed consist of equilibrium paths, photos providing the evolution of the beam deformed configurations and failure moments. The paper also includes a few remarks on the design, using the Direct Strength Method, of the beams under consideration.

Flexural behavior of precast concrete hollow-core slabs with high-strength tendons

Precast concrete hollow core (PHC) slabs have been widely used in brick and concrete structures of rural buildings due to their economic and rapid construction in China. A new PHC slab with high-strength tendons and spliced slab made of the short slabs were proposed in this paper. To investigate the flexural behavior of the slabs, full-scale tests were conducted on three PHC slabs, including one long slab and two spliced slabs with side beams. In detail, the spliced slab was assembled by two short slabs through U-type bars, anchorage bars, and post-pouring concrete. The mechanical properties of specimens were evaluated including the failure modes, strain of concrete and bars, flexural capacity and deflection. The tests results shows that the flexural performance of the spliced slab is close to that of the long slab. Subsequently, finite element models were established and validated by the test data. Based on the validated models, an additional specimen made up of long slab and side beams, was studied to further verify the reliability of the spliced slab. And parametric analysis were carried out on the spliced slab to investigate the influence of prestress of tendons, diameter of tendons, concrete strength, etc. Moreover, the cracking and failure moment of the slabs were calculated by the formulas of GB50010 and ACI318, respectively. The calculated results were compared with the test and simulation results. The results proves that the prediction values calculated by the codes on the flexural capacity of the spliced slab is not conservative. Therefore, considering a reduction factor to correct the results calculated by the codes is necessary.

Biomechanical comparison of four different fixation methods in the management of Pauwels type III femoral neck fractures: Is there a clear winner?

BackgroundCannulated screws augmented with the medial buttress plate could confer greater biomechanical stability and higher union rates than the screw fixation alone for treating young patients with Pauwels type III femoral neck fractures (FNFs). No study has evaluated the effects of distal bicortical screw fixation and biomechanical properties of buttress plate augmentation under simultaneous vertical and rotational forces, physiologically acting on the hip joint. This study aimed to compare the biomechanical properties of four methods of three cannulated screw fixation under the combined axial and torsional loading in a synthetic femur model of type III FNF. MethodsTwenty-four third-generation composite femora were divided into four groups (6 femora in each group) based on the screw fixation configuration: inverted triangle configuration (Group A), Pauwels' configuration (Group B), inverted triangle configuration combined with medial buttress plate using distal unicortical (Group C), and distal bicortical screw placement (Group D). A Pauwels type III FNF was simulated on the sawbones. Each model was subjected to the combined axial and torsional cyclic loading and subsequently tested to failure. ResultSignificant differences were determined in axial stiffness (AS) among the four groups (p = 0.024), whereas there was no significant difference in torsional stiffness (p = 0.147). The mean AS was higher in group D (639.5 ± 86.2 N/mm) than in group A (430.6 ± 94.8 N/mm), group B (426.2 ± 41.9 N/mm), and group C (451.2 ± 156.7 N/mm). Failure forces (FFs) were significantly different among four groups (p = 0.007), while there was no considerable difference in failure moment values (p = 0.555). The mean FF was significantly higher in group D (1307.1 ± 96.4 N) than in group A (1076.9 ± 371.2 N) and group B (1075.5 ± 348.3 N) (p = 0.014 and p = 0.018, respectively). There was no significant difference in the mean FF between groups D and C. ConclusionRegardless of the medial plate use, multiple cannulated systems could provide similar biomechanical results regarding torsional stiffness and failure moments. Bicortical placement of the most distal screw in medial buttress plate application could improve axial stability but not significantly affect the rotational stability of the inverted triangle screw fixation system in managing type III FNFs.

Evaluation of root lodging resistance during whole growth stage at the plant level in maize

Root lodging due to strong storm wind is a common problem in maize (Zea mays) production, leading to reduced crop yield and quality and harvest efficiency. Little information is available on quantifying effects of vertical leaf area distribution on root lodging in crops such as maize. Anti-lodging index of root was computed by the formula: ALroot = Mroot / Mwind, where AL denotes anti-lodging index, and M moment of force. Mroot, root failure moment of force equals to moment arm times max root side-pulling force measured in situ by means of the digital pole dynamometer, and Mwind, wind resultant moment of force is estimated with vertical leaf area distribution and wind speed. Two maize cultivars were examined at 5 different growth stages from V8 to physiological maturity in 2019 and 2020, in Qingdao, China. Root anti-lodging index in tested cultivars fluctuated to a small extent within any year during whole growth period excluding at V8, while there was an inter-annual shift in index means (1.23 vs 0.84). Both root failure moment and wind resultant moment increased first and then decreased with the growth stage, and their influences on root anti-lodging index varied with the year. At wind grade 6, effect sizes, as contribution to root anti-lodging index, of root moment and wind moment were respectively 0.88 and 0.98. The difference in anti-lodging index between cultivars seemed to be disappearing as wind grade goes up. Root failure moment of force positively related to single root tensile resistance, root-soil ball volume, root number and total root length, whose correlation coefficient was the maximum of 0.94. Root anti-lodging index of maize proved stable from V8 on during whole growth period, and vertical leaf area distribution played a substantial role in maize root lodging in terms of wind resultant moment. Our findings provide the insights into root lodging events in crops such as maize, and would serve an approach to assessing crop root lodging resistance in breeding and cultivation programs.

Structural-Temporal Peculiarities of Dynamic Deformation of Layered Materials.

The temporal nature of static and dynamic deformation of fibre metal laminates is discussed here. The aim of the study is to verify the proposed innovate model using layered composites. The modified relaxation model is based on the earlier formulated plasticity relaxation model for homogeneous materials. The proposed relaxation model makes it possible to describe the deformation of the layered composites from elastic to irreversible deformation, finalised by the failure moment. The developed approach allows us to consider the effects of the transition from static to dynamic loading. This means that the model-calculated dynamic limiting characteristics of the metal and the strength of brittle materials will have a determining character, depending on the loading history. The verification of the model using a glass fibre reinforced aluminium composite, glass fibre reinforced titanium composite, carbon fibre reinforced aluminium composite, and Kevlar fibre reinforced aluminium composite with different thickness ratios between metal and polymer layers is given. It is shown that the theoretical deformation curves of the metal composites at the various strain rates, finalised by brittle fracture of the polymer layers or continued irreversible deformation of remaining unbroken metal layers with destroyed polymer (fibre/epoxy) layers, are predicted. Based on the same structural−temporal parameters for five (Ti/GFRP (0/90)/Ti/GFRP(90/0)/Ti) and three (Ti/GFRP(0/90/90/0)/Ti) layers glass fibre reinforced titanium composites and the polymer layers, one-stage and two-stage stress drops during the irreversible deformation of the composite under static and dynamic loading are simulated. The change of the multi-stage fracture of the composite from static to dynamic loading and the fracture characteristic times of the polymer (100 s and 15,400 s) and the metal (8.4 ms) are correlated. Continued plastic deformation of the composite after fracture of the polymer layers is related with different values of the characteristic relaxation times of the polymer (fibre/epoxy) and the metal layers.

Fire design of stainless steel I beams prone to lateral torsional buckling under end moments

It is known that the loading type significantly influences the resistance of steel I-beams to lateral torsional buckling (LTB), which led to the development of Eurocode 3 design rules accounting for the beneficial effect of non-uniform bending in laterally unrestrained beams. New calculation formulae for stainless steel beams under fire conditions have recently been proposed for incorporation in the second generation of Eurocode 3 − their safety evaluation in the context of different bending moment diagrams is still a relevant issue that needs to be investigated. This paper presents a numerical study on the resistance of stainless steel I-beams with slender and non-slender cross-sections and undergoing LTB when acted by end moments at elevated temperatures, focusing on the influence of the moment gradient. The safety and accuracy of the Eurocode 3 design approaches (current and second generation versions), as well as a design proposal previously developed for beams with stocky stainless steel sections, are assessed through the comparison of their predictions with extensive numerical failure moments obtained with the software ANSYS. It is shown that the design proposal previously developed for stainless steel beams with stocky sections provides the best predictions, even if having considerable number of underestimations.

Dynamic response and failure mechanism characterization of composite‐metal sandwich structures under slamming impact utilizing CEL method

AbstractSlamming is a complicated fluid–structure coupling process accompanied with complex transfer of load and energy, which may pose a significant risk to the overall safety of structure. This paper aims to evaluate the dynamic response and elucidate the failure mechanism of composite‐metal sandwich structures under slamming impact. Firstly, a reliable numerical simulation process is established based on CEL method in ABAQUS/Explicit combining with a VUMAT subroutine, whose effectiveness is verified through the comparison with published experimental results. Subsequently, dynamic response of the sandwich structures is investigated considering the influence of slamming velocity and material constituent. Meanwhile, damage evolution and critical failure mechanism are assessed through progressive damage analysis. Results show that CF‐Al‐CF case owns the best mechanical performance and the latest ultimate failure moment. The overall performance of sandwich structure is mainly dependent on the mechanical properties of skin. Additionally, damage of Al‐CF‐Al case is more sensitive to the variation of velocity compared with that of CF‐Al‐CF and Al‐Al‐Al cases, which indicates that the ductility of core is responsible for ultimate damage. Moreover, extensively distributed matrix tension damage can be identified as the critical damage mode, which may further cause debonding damage and even fiber fracture.