China
Africa
Explore chapters and articles related to this topic
Testing of Composites and Their Constituents
Published in Manoj Kumar Buragohain, Composite Structures, 2017
When a body containing a crack is subjected to external forces, a portion of the work done by the external forces is stored as strain energy and the rest drives the crack to grow. Strain energy release rate is a parameter that represents the energy available for crack growth. Fracture criterion based on strain energy release rate states that crack growth occurs when the energy available for crack growth is more than the work required to create a new crack area. Mathematically, strain energy release rate is defined as G=d(W−U)dA where
Study on intralaminar crack propagation mechanisms in single- and multi-layer 2D woven composite laminate
Published in Mechanics of Advanced Materials and Structures, 2022
Ping Cheng, Yong Peng, Kui Wang, Yi-Qi Wang, Chao Chen
The strain energy release rate (G) describes the energy required to produce a new crack surface. Thence they reflect the crack propagation status. For the propagation of the plain woven composite mode I crack used in this paper (refer to Figure 2(a)), the equation for GI is as follows [26]: where a11 = 1/E11, a12 = −mu12/E11, a22 = 1/E22, a66 = 1/G12, they are the elasticity of the composite material, respectively. KI is stress intensity factors for mode I, E11, E22 are the elastic modulus in the direction of 11 and 22, G12 is the shear modulus in the direction of 12, mu12 is the Poisson's ratio in the direction of 12. where a is crack length, w is laminate width, is tension stress, is shape factor function [27–29]. The strain energy release rate of the different crack lengths by Eq. (2), the calculating result shown in Figure 11. As the crack length increases, the strain energy release rate increases. The increase of the crack length reduces the load-bearing length of the specimen, and the crack propagates more easily.
Crack propagation mechanism of flexible composite stiffened bags under pressure load
Published in Ships and Offshore Structures, 2023
Zhixin Peng, Shengjie Xu, Yuchao Yuan, Wenyong Tang
1)In fracture mechanics, fracture problems are generally studied in three basic types: Mode I (Opening Mode), Mode II (Sliding Mode) and Mode III (Anti-plane Shear Mode), as shown in Figure 2, which correspond to three critical strain energy release rates: GI, GII, GIII. The crack will expand only when the strain energy release rates GI, GII, and GIII at the crack tip are respectively greater than the corresponding critical strain energy release rates GIC, GIIC, and GIIIC (Gao 1986).