A Cohesive Zone Model for Simulation of the Bonding and Debonding in Metallic Composite Structures - Experimental Validations

2014 ◽  
Vol 622-623 ◽  
pp. 443-452 ◽  
Author(s):  
R. Kebriaei ◽  
Alexander Mikloweit ◽  
I.N. Vladimirov ◽  
Markus Bambach ◽  
S. Reese ◽  
...  

Flexible and economic production of composite structures which include functional layersrequires new manufacturing techniques. Joining by plastic deformation is a powerful technique whichis widely used in production processes to create metal composites [1]. The use of plastic deformationin joining processes offers improved accuracy, reliability and environmental safety [2]. The presentstudy deals with modeling of the bonding and debonding behavior in metallic composite structures.Therefore, a general cohesive zone element formulation in the framework of zero-thickness interfaceelements is developed. This enables the accurate and efficient modeling of the interface based on aninterfacial traction-separation law. The paper is concluded by a detailed description of the processsimulation and a comparison of its results with experimental data.

2019 ◽  
Vol 2019 ◽  
pp. 1-16 ◽  
Author(s):  
F. Di Caprio ◽  
S. Saputo ◽  
A. Sellitto

Composite laminates are characterized by high mechanical in-plane properties while experiencing, on the contrary, a poor out-of-plane response. The composite laminates, indeed, are often highly vulnerable to interlaminar damages, also called “delaminations.” One of the main techniques used for the numerical prediction of interlaminar damage onset and growth is the cohesive zone model (CZM). However, this approach is characterised by uncertainties in the definition of the parameters needed for the implementation of the cohesive behaviour in the numerical software. To overcome this issue, in the present paper, a numerical-experimental procedure for the calibration of material parameters governing the mechanical behaviour of CZM based on cohesive surface and cohesive element approaches is presented. Indeed, by comparing the results obtained from the double cantilever beam (DCB) and end-notched flexure (ENF) experimental tests with the corresponding numerical results, it has been possible to accurately calibrate the parameters of the numerical models needed to simulate the delamination growth phenomenon at coupon level.


2005 ◽  
Vol 492-493 ◽  
pp. 447-452 ◽  
Author(s):  
Glaucio H. Paulino ◽  
Zheng Yu Zhang

This paper presents a Cohesive Zone Model (CZM) approach for investigating dy- namic failure processes in homogeneous and Functionally Graded Materials (FGMs). The failure criterion is incorporated in the CZM using both a ßnite cohesive strength and work to fracture in the material description. A novel CZM for FGMs is explored and incorporated into a ßnite element framework. The material gradation is approximated at the element level using a graded element formulation. A numerical example is provided to demonstrate the eácacy of the CZM approach, in which the inàuence of the material gradation on the crack branching pattern is studied.


2018 ◽  
Vol 877 ◽  
pp. 436-445
Author(s):  
J. Muthupandian ◽  
Koovaparambil Ramunny Pradeep

Composite structures are prone to delamination/de-bond and effective tool to simulate de-lamination is cohesive zone model. Cohesive zone model uses multiple adhesive failure parameters. The influence of adhesive parameters on the delamination and fracture of Double cantilever Beam, subjected to Mode-I loading through finite element simulations is studied usingExponential Cohesive Zone Model (ECZM). Influence of Normal stress (σ), normal deflection (δn) and tangential deflection (δt) on the de-bond propagation is examined.From the analysis it is found that the tangential deflection (δt) has negligible impact on Mode-I loading and fracture of the specimen. Significant effects are seen for the perturbation of Normal stress (σ) and Normal deflection (δn). A Finite element based ECZM for composite layer (HTS/M18) with EPG 2601 adhesive is proposed. The model is validated by comparing with test data.


2014 ◽  
Vol 2014 ◽  
pp. 1-12 ◽  
Author(s):  
J. P. Lin ◽  
J. F. Wang ◽  
R. Q. Xu

Push-out tests were widely used to determine the shear bearing capacity and shear stiffness of shear connectors in steel-concrete composite structures. The finite element method was one efficient alternative to push-out testing. This paper focused on a simulation analysis of the interface between concrete slabs and steel girder flanges as well as the interface of the shear connectors and the surrounding concrete. A cohesive zone model was used to simulate the tangential sliding and normal separation of the interfaces. Then, a zero-thickness cohesive element was implemented via the user-defined element subroutine UEL in the software ABAQUS, and a multiple broken line mode was used to define the constitutive relations of the cohesive zone. A three-dimensional numerical analysis model was established for push-out testing to analyze the load-displacement curves of the push-out test process, interface relative displacement, and interface stress distribution. This method was found to accurately calculate the shear capacity and shear stiffness of shear connectors. The numerical results showed that the multiple broken lines mode cohesive zone model could describe the nonlinear mechanical behavior of the interface between steel and concrete and that a discontinuous deformation numerical simulation could be implemented.


2020 ◽  
Vol 10 (19) ◽  
pp. 6640
Author(s):  
Zhonghua Shi ◽  
Zhenhang Kang ◽  
Qiang Xie ◽  
Yuan Tian ◽  
Yueqing Zhao ◽  
...  

An effective deicing system is needed to be designed to conveniently remove ice from the surfaces of structures. In this paper, an ultrasonic deicing system for different configurations was estimated and verified based on finite element simulations. The research focused on deicing efficiency factor (DEF) discussions, prediction, and validations. Firstly, seven different configurations of Lead zirconate titanate (PZT) disk actuators with the same volume but different radius and thickness were adopted to conduct harmonic analysis. The effects of PZT shape on shear stresses and optimal frequencies were obtained. Simultaneously, the average shear stresses at the ice/substrate interface and total energy density needed for deicing were calculated. Then, a coefficient named deicing efficiency factor (DEF) was proposed to estimate deicing efficiency. Based on these results, the optimized configuration and deicing frequency are given. Furthermore, four different icing cases for the optimize configuration were studied to further verify the rationality of DEF. The effects of shear stress distributions on deicing efficiency were also analyzed. At same time, a cohesive zone model (CZM) was introduced to describe interface behavior of the plate and ice layer. Standard-explicit co-simulation was utilized to model the wave propagation and ice layer delamination process. Finally, the deicing experiments were carried out to validate the feasibility and correctness of the deicing system.


2021 ◽  
Vol 11 (1) ◽  
pp. 456
Author(s):  
Yanglong Zhong ◽  
Liang Gao ◽  
Xiaopei Cai ◽  
Bolun An ◽  
Zhihan Zhang ◽  
...  

The interface crack of a slab track is a fracture of mixed-mode that experiences a complex loading–unloading–reloading process. A reasonable simulation of the interaction between the layers of slab tracks is the key to studying the interface crack. However, the existing models of interface disease of slab track have problems, such as the stress oscillation of the crack tip and self-repairing, which do not simulate the mixed mode of interface cracks accurately. Aiming at these shortcomings, we propose an improved cohesive zone model combined with an unloading/reloading relationship based on the original Park–Paulino–Roesler (PPR) model in this paper. It is shown that the improved model guaranteed the consistency of the cohesive constitutive model and described the mixed-mode fracture better. This conclusion is based on the assessment of work-of-separation and the simulation of the mixed-mode bending test. Through the test of loading, unloading, and reloading, we observed that the improved unloading/reloading relationship effectively eliminated the issue of self-repairing and preserved all essential features. The proposed model provides a tool for the study of interface cracking mechanism of ballastless tracks and theoretical guidance for the monitoring, maintenance, and repair of layer defects, such as interfacial cracks and slab arches.


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