scholarly journals Crashworthiness behavior of aircraft sandwich structure with honeycomb core under bending load.

Author(s):  
S E Sadiq ◽  
S H Bakhy ◽  
M J Jweeg
2021 ◽  
Vol 39 (1A) ◽  
pp. 153-166
Author(s):  
Sadiq E. Sadiq ◽  
Muhsin J. Jweeg ◽  
Sadeq H. Bakhy

In this paper, the strength of  aircraft sandwich structure with honeycomb core under bending load was evaluated theoretically and experimentally based on failure mode maps. A failure mode map for the loading under three-point bending was constructed theoretically to specify the failure modes and corresponding load. Three point bending test for aluminum honeycomb sandwich beam has been achieved to measure the peak load and maximum deflection. The obtained results elucidated a good agreement between the theoretical solutions and experimental tests, where the error ratio was not exceeded 12%. The core height, the cell size and the cell wall thickness were selected to explore the effect of honeycomb parameters on the strength of sandwich structure. In order to obtain the optimum solution of peak load and maximum deflection and energy absorption, Response Surface Methodology (RSM) was used. Results showed that the maximum bending load, minimum deflection, and maximum energy absorption were found at 25 mm core height, 10 mm size cell and 1 mm  cell wall thickness. The optimal value of maximum bending load, minimum deflection and maximum energy absorption were 1975.3415 N, 1.0402 mm and 1.0229 J respectively.


Author(s):  
Wenwei Hu ◽  
Jun Liu ◽  
Pan Zhang ◽  
Yuansheng Cheng

Abstract I-core sandwich structure has great potential in the application of hull structure construction due to its high specific strength and relatively simple manufacturing process. The topic on the study of mechanical properties of I-core sandwich structure under bending loads is of interest to structural designers since the structure is often subjected to bending loads in engineering applications. In this paper, a metallic I-core sandwich beam with longitudinal girder was designed and manufactured using laser welding technique, and finally tested under four-point bend loading. The elastic-plastic behaviors and the ultimate load carrying capacity of this novel beam structure were obtained. A numerical model was developed to investigate the mechanical properties of this novel beam structure by finite element method. The results of the numerical model were compared with experimental data. Stress components of the front face and back face in the failure process were analyzed and discussed to investigate the failure of them. Results showed that the huge local bending stresses of plate caused the failure of the front face and back face. Finally, an improved scheme for the test was proposed to provide a pure bending load, which was proved by finite element simulation. All the findings aim to guide the engineering application of this structure.


Forests ◽  
2020 ◽  
Vol 11 (8) ◽  
pp. 886 ◽  
Author(s):  
Jingxin Hao ◽  
Xinfeng Wu ◽  
Gloria Oporto-Velasquez ◽  
Jingxin Wang ◽  
Gregory Dahle

The transverse compression property is one of most important aspects of the mechanical performance of a sandwich structure with a soft core. An experiment, analytical method and three digital strain measurement systems were applied to investigate the compression behavior and the failure mechanism for a wood-based sandwich structure with a novel Taiji honeycomb core. The results show that the structure of the Taiji honeycomb can improve dramatically on compression strength and modulus of composite compared to that of a traditional hexagonal one. There was no obvious deflection in the transverse direction detected by the three digital images before the buckling of the honeycomb occurred. An analytical equation between the key structure parameters and properties of the composite were applied to predict its threshold stresses and modulus. The properties of the core determine the strength of the entire structure, but the compression strength decreases slightly with an elevated core thickness, and its effect on the compression modulus can be neglected. Both the surface sheets and loading speed have little impact on the compression strength and modulus, respectively.


Author(s):  
M.R. Ashok ◽  
M. Manojkumar ◽  
P.V. Inbanaathan ◽  
R. Shanmuga Prakash

This paper details the fabrication and flexural testing of sandwich structure with Aluminium honeycomb core with Aluminium face skins. The material for the face skin is aluminium 1100 and for the core is Aluminium AA8011. The cell size obtained by fabrication is 7mm. The specimen is prepared and tested as per the ASTM standard C393/C393M-11 on a three-point bending test to obtain the ultimate core shear strength and the face skin strength. Finite element analysis is also carried out to validate the experimental test.


Author(s):  
Vidyasagar Matta ◽  
J Suresh Kumar ◽  
Duddu Venkataraviteja ◽  
Guggulla Bharath Kumar Reddy

2015 ◽  
Vol 99 ◽  
pp. 405-412 ◽  
Author(s):  
Chun Lu ◽  
Mingyue Zhao ◽  
Liu Jie ◽  
Jing Wang ◽  
Yu Gao ◽  
...  

2010 ◽  
Vol 97-101 ◽  
pp. 4363-4366
Author(s):  
Hui Liu ◽  
Jun Yan Liu ◽  
Yang Wang ◽  
Hui Juan Li

Lock-in thermography (LT), that is active infrared testing technology, mainly includes optical lock-in thermography (OLT) and ultrasound lock-in thermography (ULT). LT can be used to detect unbonds between honeycomb core and face sheet of sandwich structures. However, modulation frequency is an important influencing factor. In this paper, the principles of LT are represented, in experimental detections of simulated unbonds in honeycomb sandwich structures with Al-face sheet and CFRP-face sheet using OLT and ULT, detectability of OLT and ULT is compared and analyzed, effect of modulation frequency is researched and the optimal frequencies are obtained.


Sign in / Sign up

Export Citation Format

Share Document