Lixiang Wang¹, Longfei Wen^2,3, Rong Tian^2,3,*, Chun Feng^1,4,*

The International Conference on Computational & Experimental Engineering and Sciences, Vol.30, No.3, pp. 1-2, 2024, DOI:10.32604/icces.2024.011137

Abstract The extended finite element method (XFEM) has been successful in crack analysis but faces challenges in modeling multiple cracks. One challenge is the linear dependence and ill-conditioning of the global stiffness matrix, while another is the geometric description for multiple cracks. To address the first challenge, the Improved XFEM (IXFEM) [1–9] is extended to handle multiple crack problems, effectively eliminating issues of linear dependence and ill-conditioning. Additionally, to overcome the second challenge, a novel level set templated cover cutting method (LSTCCM) [10] is proposed, which combines the advantages of the level set method and cover More >

Diguang Gong¹, Junbin Chen¹, Cheng Cheng², Yuanyuan Kou^2,*

Energy Engineering, Vol.121, No.2, pp. 425-437, 2024, DOI:10.32604/ee.2023.030196 - 25 January 2024

Abstract Horizontal well-stimulation is the key to unconventional resource exploration and development. The development mode of the well plant helps increase the stimulated reservoir volume. Nevertheless, fracture interference between wells reduces the fracturing effect. Here, a 2D hydro-mechanical coupling model describing hydraulic fracture (HF) propagation is established with the extended finite element method, and the effects of several factors on HF propagation during multiple wells fracturing are analyzed. The results show that with an increase in elastic modulus, horizontal principal stress difference and injection fluid displacement, the total fracture area and the reservoir stimulation efficiency are More >

Zongying Fu¹, Yongdong Zhou¹, Tingguo Yan², Yun Lu^1,*

Journal of Renewable Materials, Vol.11, No.1, pp. 93-102, 2023, DOI:10.32604/jrm.2023.021808 - 10 August 2022

Abstract Drying crack is a common phenomenon occurring during moisture discharge from wood, reducing efficient wood utilization. Drying crack is primarily caused by drying stress, and the reasonable methods for determining drying stress are sparse. In this study, the initiation and propagation of cracks during wood discs drying were simulated using the extended finite element method (XFEM). The distribution of drying stress and displacement was analyzed at different crack conditions based on the simulation results. This study aimed to solve the problem of the limitation of drying stress testing methods and provide a new idea for More >

Ying Wang^1,*, Zheng Yan¹, Zhen Wang²

CMES-Computer Modeling in Engineering & Sciences, Vol.127, No.2, pp. 549-574, 2021, DOI:10.32604/cmes.2021.014727 - 19 April 2021

Abstract Due to the complex structure and dense weld of the orthotropic steel bridge deck (OSBD), fatigue cracks are prone to occur in the typical welding details. Welding residual stress (WRS) will cause a plastic zone at the crack tip. In this paper, an elastoplastic constitutive model based on the Chaboche kinematic hardening model was introduced, and the extended finite element method (XFEM) was used to study the influence of material elastoplasticity and crack tip plastic zone on the law of fatigue crack propagation. By judging the stress state of the residual stress field at the… More >

Ying Wang*, Zhen Wang

The International Conference on Computational & Experimental Engineering and Sciences, Vol.22, No.4, pp. 176-176, 2019, DOI:10.32604/icces.2019.05665

Abstract Due to stress concentration as well as welding residual stress, fracture due to vehicle fatigue loads is easy to occur in the weld and its adjacent position of long-span bridge, especially at the toe of weld between the U-rib and orthotropic steel bridge deck. In order to investigate the fatigue crack propagation mechanism of the toe of weld in long-span bridge, a multi-scale finite element model including the whole bridge, local components, the welding details and cracks was established firstly. And then, based on birth and death element technology, the welding heat and structural coupling… More >

Changwei Huang^1,*, Philip A. Williams²

CMES-Computer Modeling in Engineering & Sciences, Vol.120, No.2, pp. 261-272, 2019, DOI:10.32604/cmes.2019.06681

Abstract This paper examines the evolution of the interfacial deflection energy release rates in multilayered structures under four-point bending. The J-integral and the extended finite element method (XFEM) are adopted to investigate the evolution of the interfacial deflection energy release rates of composite structures. Numerical results not only verify the accuracy of analytical solutions for the steady-state interfacial deflection energy release rate, but also provide the evolutionary history of the interfacial deflection energy release rate under different crack lengths. In addition, non-dimensional parametric analyses are performed to discuss the effects of normalized ratios of the crack length, More >

N. Vu-Bac¹, H. Nguyen-Xuan², L. Chen³, S. Bordas⁴, P. Kerfriden⁴, R.N. Simpson⁴, G.R. Liu⁵, T. Rabczuk¹

CMES-Computer Modeling in Engineering & Sciences, Vol.73, No.4, pp. 331-356, 2011, DOI:10.3970/cmes.2011.073.331

Abstract This paper aims to incorporate the node-based smoothed finite element method (NS-FEM) into the extended finite element method (XFEM) to form a novel numerical method (NS-XFEM) for analyzing fracture problems of 2D elasticity. NS-FEM uses the strain smoothing technique over the smoothing domains associated with nodes to compute the system stiffness matrix, which leads to the line integrations using directly the shape function values along the boundaries of the smoothing domains. As a result, we avoid integration of the stress singularity at the crack tip. It is not necessary to divide elements cut by cracks More >

Jun Xu^1,2, Yibing Li¹, Xi Chen^2,3, Yuan Yan^2,3, Dongyun Ge^4,1, Bohan Liu¹

CMC-Computers, Materials & Continua, Vol.18, No.2, pp. 183-212, 2010, DOI:10.3970/cmc.2010.018.183

Abstract The crack pattern in a PVB laminated windshield upon head impact is of considerable interest because it contains important information on energy mitigation, pedestrian protection, and accident reconstruction. We carry out a systematic numerical study based on the extended finite element method (XFEM), to investigate the effects of various material and system variables, including the impact speed, effective head mass, PVB interlayer material thickness and property, windshield curvature, aspect ratio and size, boundary constraint, impact angle and off-center impact, on the parameters characterizing the resulting crack pattern, i.e. the crack length, crack angle and circumferential More >