Tough elastomers and gels have garnered broad research interest due to their wide-ranging potential ***,during the loading and unloading cycles,a clear stress softening behavior can be observed in many material system...
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Tough elastomers and gels have garnered broad research interest due to their wide-ranging potential ***,during the loading and unloading cycles,a clear stress softening behavior can be observed in many material systems,which is also named as the Mullins *** this work,we aim to provide a complete review of the Mullins effect in soft yet tough materials,specifically focusing on nanocomposite gels,double-network hydrogels,and multi-network *** first revisit the experimental observations for these soft *** then discuss the recent developments of constitutive models,emphasizing novel developments in the damage mechanisms or network *** phenomenological models will also be briefly *** attention is then placed on the anisotropic and multiaxial modeling *** is demonstrated that most of the existing models fail to accurately predict the multiaxial data,posing a significant challenge for developing future anisotropic models tailored for tough gels and elastomers.
An explicit form of the elastic strain-energy function for direction-dependent large elastic strain behaviors of soft fiber-reinforced composites is first presented based upon a decoupled approach for simulating compl...
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An explicit form of the elastic strain-energy function for direction-dependent large elastic strain behaviors of soft fiber-reinforced composites is first presented based upon a decoupled approach for simulating complex nonlinear coupling *** this form,the exact closed-form solutions are then obtained for the uniaxial tension responses in the fiber and cross-fiber *** such exact solutions,the issue of simultaneously simulating strongly coupling nonlinear responses in the fiber and cross-fiber directions may be reduced to the issue of separately treating each decoupled uniaxial stress-strain response,thus bypassing usual complexities and uncertainties involved in identifying a large number of strongly coupled adjustable *** numerical examples given are in good agreement with the experimental data for large strain responses.
The relationship between the protective performance of flexible polymer material and material parameters(elasticmodulus,viscosity coefficient)is explored,an impact collision motion equation between two bodies is estab...
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The relationship between the protective performance of flexible polymer material and material parameters(elasticmodulus,viscosity coefficient)is explored,an impact collision motion equation between two bodies is establishedfrom the viscoelastic material constitutive,and the relationship between the kinematic response and the materialparameters is *** on the Kelvin constitutive model,a theoretical model for impact between the pro-tective body and the protected body is established,then the dynamic response is *** feasibility of themodel was verified by drop hammer experiment,and the material parameters(elastic modulus,viscosity coeffi-cient)were obtained by *** model is discretized and the relationship between local impact response andmaterial parameters is *** discussion results on the relationship between the impact response and theprotective material performance indicate that adjusting the elastic modulus,viscosity coefficient,and thicknessof the protective material can effectively improve protective effect.
For real-time dynamic substructure testing(RTDST),the influence of the inertia force of fluid specimens on the stability and accuracy of the integration algorithms has never been ***,this study proposes to investigate...
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For real-time dynamic substructure testing(RTDST),the influence of the inertia force of fluid specimens on the stability and accuracy of the integration algorithms has never been ***,this study proposes to investigate the stability and accuracy of the central difference method(CDM)for RTDST considering the specimen mass participation ***,the theory of the CDM for RTDST is ***,the stability and accuracy of the CDM for RTDST considering the specimen mass participation coefficient are ***,numerical simulations and experimental tests are conducted for verifying the effectiveness of the *** study indicates that the stability of the algorithm is affected by the mass participation coefficient of the specimen,and the stability limit first increases and then decreases as the mass participation coefficient *** most cases,the mass participation coefficient will increase the stability limit of the algorithm,but in specific circumstances,the algorithm may lose its *** stability and accuracy of the CDM considering the mass participation coefficient are verified by numerical simulations and experimental tests on a three-story frame structure with a tuned liquid damper.
Bistable curved shells have become a promising low-cost application in energy absorption fields owing to recentadvances in material and *** research has been conducted to improve their energy absorptioneffect through ...
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Bistable curved shells have become a promising low-cost application in energy absorption fields owing to recentadvances in material and *** research has been conducted to improve their energy absorptioneffect through forward prediction and single-objective ***,these approaches may not fully explore their functional *** this study,we propose a multi-objective optimization framework based on theprinciple of main objective optimization that combines neural networks and genetic *** energy absorption effect and backward snapping force of the bistable curved shell are improved ***,a reverse design algorithm is developed to generate the preset load-displacement curve,which further expandsthe application of machine learning methods in the field of multi-objective *** combination ofmachine learning and multi-objective optimization is highly effective for building meta-structures with specificperformance requirements and has potential applications in solving complex optimization tasks in various fields.
For fragile products,packaging requires cushioning protection to prevent irreversible damage from accidental falls,transportation impacts,and other *** new polyurethane foam(PUF)material demonstrates superior cushioni...
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For fragile products,packaging requires cushioning protection to prevent irreversible damage from accidental falls,transportation impacts,and other *** new polyurethane foam(PUF)material demonstrates superior cushioning and vibration isolation performance in practical applications,effectively minimizing damage from *** and vibration experiments were conducted on packages comprising novel PUF,expandable polyethylene,ethylene-vinyl acetate copolymer foam,and *** verify that the new PUF material outperforms in cushioning and vibration isolation,as observed from the acceleration ***,a random vibration analysis of a packaging unit involving different thicknesses of PUF materials and bracelets reveals the enhanced vibration isolation effect within a specific thickness *** vibration results of the bracelet’s outer packaging align closely with finite element simulation results,validating the effectiveness of designing and optimizing the outer *** finite element simulation,deeper understanding and prediction of the bracelet’s vibration response under various conditions is achieved,facilitating optimized packaging design for better protection and vibration damping.
A new finite strain elastoplastic J2-flow model is established with an explicit formulation of work-hardening and softening effects up to eventual failure,in which both a new flow rule free of yielding and an asymptot...
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A new finite strain elastoplastic J2-flow model is established with an explicit formulation of work-hardening and softening effects up to eventual failure,in which both a new flow rule free of yielding and an asymptotically vanishing stress limit are *** novelties of this new model are as follows:(i)Fatigue failure effects under repeated loading conditions with either constant or varying amplitudes are automatically characterized as inherent response features;(ii)neither additional damage-like variables nor failure criteria need to be involved;and(iii)both high-and low-cycle fatigue effects may be simultaneously treated.A fast and efficient algorithm of high accuracy is proposed for directly simulating high-and medium-high-cycle fatigue failure effects under repeated loading *** this goal,a direct and explicit relationship between the fatigue life and the stress amplitude is obtained by means of explicit and direct procedures of integrating the coupled elastoplastic rate equations for any given number of loading-unloading cycles with varying stress *** examples suggest that the new algorithm is much more fast and efficient than usual tedious and very time-consuming integration procedures.
Photo-responsive nematic polymers can transduce light into mechanical work,but the rate is limited by the quasi-static *** enhance the work output,a strat・egy of exploiting photo-triggered snap-through of glassy nemat...
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Photo-responsive nematic polymers can transduce light into mechanical work,but the rate is limited by the quasi-static *** enhance the work output,a strat・egy of exploiting photo-triggered snap-through of glassy nematic shallow spherical shells with hemeotropic director alignment is examined *** criterion for the nonlinear instability is derived analytically by using the modified iteration *** is shown that,for thin shells of small height and large basal radius,snap-through can be caused by an incident light with moderate irradiation *** phenomenon may inspire some new designs of contactless and ultra-fast actuation devices with high-rate output of mechanical work.
A trigger system is typically employed in active seismic testing to trigger and synchronize multichannel surface wave data *** effect of the trigger system on the dispersion image of surface waves is empirically known...
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A trigger system is typically employed in active seismic testing to trigger and synchronize multichannel surface wave data *** effect of the trigger system on the dispersion image of surface waves is empirically known to be negligible,however,theoretical explanation regarding the effect of the trigger system is *** study systematically examines the theory for surface wave dispersion analysis and proves that the effect of the trigger system on a dispersion image is negligible via a solid theoretical ***,based on the new theoretical explanation,an alternative method that uses only the relative phase difference between sensors to extract dispersion characteristics with better conceptual clarity is *** active surface wave testing cases are considered to validate the theory and *** results indicate that(1)an accurate trigger system is not necessary for surface wave data acquisition,and(2)it is unnecessary to assume that the impact point is the generation point of the surface waves for the experimental dispersion analysis.
The large-span spatial hub structure is an important urban lifeline project with complex structure form and many types of internal non-structural components. As one of the main non-structural components, the safety of...
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