Assessment of the load carrying performance of composite cross joints

Composite cross joints are common structures in an airframe. When this type of joint is used on an air inlet stiffened structure, it will undertake large bending moment, especially under overpressure of the engine. In this paper, two types of cross joints are tested experimentally and simulated to investigate the load bearing characteristics and make comparative remarks. Four-point bending tests are conducted and the load deflection curves are obtained; besides, the damage pattern of the joints is reported. Based on composite progressive damage model, the numerical simulations have a good agreement with experimental results, revealing the joint failure mechanism and fastener force feature of various joints. The comparative assessment of two types of joints is summarized.

Download Full-text

Development of a strain-rate dependent progressive damage model for crash analysis of composite laminates

DYMAT 2009 - 9th International Conferences on the Mechanical and Physical Behaviour of Materials under Dynamic Loading ◽

10.1051/dymat/2009178 ◽

2009 ◽

Author(s):

M. M. Shokrieh ◽

M. O. Jamal

Keyword(s):

Strain Rate ◽

Composite Laminates ◽

Damage Model ◽

Progressive Damage ◽

Crash Analysis ◽

Rate Dependent ◽

Progressive Damage Model

Download Full-text

Progressive damage characteristics of screwed single-lap CFRPI-metal joint subjected to tensile loading at RT and 350°C

Journal of Composite Materials ◽

10.1177/0021998320985595 ◽

2021 ◽

pp. 002199832098559

Author(s):

Yun-Tao Zhu ◽

Jun-Jiang Xiong ◽

Chu-Yang Luo ◽

Yi-Sen Du

Keyword(s):

Damage Model ◽

Tensile Loading ◽

Tensile Tests ◽

Displacement Curve ◽

Progressive Damage ◽

Damage Characteristics ◽

Metal Joint ◽

Static Tensile ◽

Strength And Stiffness ◽

Progressive Damage Model

This paper outlines progressive damage characteristics of screwed single-lap CFRPI-metal joints subjected to tensile loading at RT (room temperature) and 350°C. Quasi-static tensile tests were performed on screwed single-lap CCF300/AC721-30CrMnSiA joint at RT and 350°C, and the load versus displacement curve, strength and stiffness of joint were gauged and discussed. With due consideration of thermal-mechanical interaction and complex failure mechanism, a modified progressive damage model (PDM) based on the mixed failure criterion was devised to simulate progressive damage characteristics of screwed single-lap CCF300/AC721-30CrMnSiA joint, and simulations correlate well with experiments. By using the PDM, the effects of geometry dimensions on mechanical characteristics of screwed single-lap CCF300/AC721-30CrMnSiA joint were analyzed and discussed.

Download Full-text

A progressive damage model for three-dimensional woven composites under ballistic impact loading

Engineering Research Express ◽

10.1088/2631-8695/ab3ba6 ◽

2019 ◽

Vol 1 (1) ◽

pp. 015028

Author(s):

Yongqi Yang ◽

Li Zhang ◽

Licheng Guo ◽

Suyang Zhong ◽

Jiuzhou Zhao ◽

...

Keyword(s):

Impact Loading ◽

Damage Model ◽

Three Dimensional ◽

Ballistic Impact ◽

Woven Composites ◽

Progressive Damage ◽

Progressive Damage Model

Download Full-text

A progressive damage model of composite laminates under low-velocity impact

Xibei Gongye Daxue Xuebao/Journal of Northwestern Polytechnical University ◽

10.1051/jnwpu/20213910037 ◽

2021 ◽

Vol 39 (1) ◽

pp. 37-45

Author(s):

Junjie Zhou ◽

Shengnan Wang

Keyword(s):

Composite Laminates ◽

Impact Force ◽

Damage Model ◽

Low Velocity Impact ◽

Progressive Damage ◽

Low Velocity ◽

Damage Development ◽

Velocity Impact ◽

Progressive Damage Model ◽

Matrix Damage

In this paper, a progressive damage model for studying the dynamic mechanical response and damage development of composite laminates under low-velocity impact was established. The model applied the Hashin and Hou failure criteria to predict the initiation of intra-laminar damage (fiber and matrix damage); a linear degradation scheme combined with the equivalent displacement method was adopted to simulate the damage development; a cohesive zone model with the bilinear traction-separation relationship was used to predict delamination. A user material subroutine VUMAT was coded, and the simulation analysis of carbon fiber reinforcement composite laminates subjected to 25 J impact was performed via commercial software ABAQUS. The predicted impact force-time curve, impact force-displacement curve, and damage distribution contours among the layers were in a good agreement with the experimental, which verified the proposed model. According to the simulation results, the fiber damage and matrix damage were analyzed, and the expansion of delamination was discussed.

Download Full-text

A Strain Rate Dependent Progressive Damage Model for Carbon Fiber Woven Composites under Low Velocity Impact

Journal of Physics Conference Series ◽

10.1088/1742-6596/2101/1/012073 ◽

2021 ◽

Vol 2101 (1) ◽

pp. 012073

Author(s):

Xueyao Hu ◽

Jiaojiao Tang ◽

Wei Xiao ◽

Kepeng Qu

Keyword(s):

Strain Rate ◽

Damage Model ◽

Low Velocity Impact ◽

Woven Composites ◽

Progressive Damage ◽

Low Velocity ◽

Velocity Impact ◽

Rate Dependent ◽

Plane Direction ◽

Progressive Damage Model

Abstract A progressive damage model was presented for carbon fiber woven composites under low velocity impact, considering the strain rate sensitivity of both mechanical properties and failure mechanisms. In this model, strain rate dependency of elastic modulus and nominal strength along in-plane direction are considered. Based on the Weibull distribution, stiffness progressive degradation is conducted by introducing strain rate dependent damage variables for distinct damage modes. With the model implemented in ABAQUS/Explicit via user-defined material subroutine (VUMAT), the mechanical behavior and possible damage modes of composites along in-plane direction can be determined. Furthermore, a bilinear traction separation model and a quadratic stress criterion are applied to predict the initiation and evolution of interlaminar delamination. Comparisons are made between the experimental results and numerical simulations. It is shown that the mechanical response and damage characteristics under low velocity impact, such as contact force history and delamination, are more consistent with the experimental results when taken the strain rate effect into consideration.

Download Full-text