First-Ply Failure Behavior of Laminated Composite Skew Plates of Various Edge Conditions

Author(s):  
D. Chatterjee ◽  
A. Ghosh ◽  
D. Chakravorty
Author(s):  
Chian-Fong Yen ◽  
Robert Kaste ◽  
Jian Yu ◽  
Charles Chih-Tsai Chen ◽  
Nelson Carey

Design of the new generation of aircraft is driven by the vastly increased cost of fuel and the resultant imperative for greater fuel efficiency. Carbon fiber composites have been used in aircraft structures to lower weight due to their superior stiffness and strength-to-weight properties. However, carbon composite material behavior under dynamic ballistic and blast loading conditions is relatively unknown. For aviation safety consideration, a computational constitutive model has been used to characterize the progressive failure behavior of carbon laminated composite plates subjected to ballistic impact conditions. Using a meso-mechanics approach, a laminated composite is represented by a collection of selected numbers of representative unidirectional layers with proper layup configurations. The damage progression in a unidirectional layer is assumed to be governed by the strain-rate dependent layer progressive failure model using the continuum damage mechanics approach. The composite failure model has been successfully implemented within LS-DYNA as a user-defined material subroutine. In this paper, the ballistic limit velocity (V50) was established for a series of laminates by ballistic impact testing. Correlation of the predicted and measured V50 values has been conducted to validate the accuracy of the ballistic modeling approach for the selected carbon composite material. The availability of this modeling tool will greatly facilitate the development of carbon composite structures with enhanced ballistic and blast survivability.


2019 ◽  
Vol 54 (4) ◽  
pp. 485-499
Author(s):  
Chian-Fong Yen ◽  
Bob Kaste ◽  
Charles Chih-Tsai Chen ◽  
Nelson Carey

The design of the next generation of aeronautical vehicles is driven by the vastly increased cost of fuel and the resultant imperative for greater fuel efficiency. Carbon fiber composites have been used in aeronautical structures to lower weight due to their superior stiffness and strength-to-weight properties. However, carbon composite material behavior under dynamic ballistic impact and blast loading conditions is relatively unknown. For aviation safety consideration, a computational constitutive model has been used to characterize the progressive failure behavior of carbon laminated composite plates subjected to ballistic impact and blast loading conditions. Using a meso-mechanics approach, a laminated composite is represented by a collection of selected numbers of representative unidirectional layers with proper layup configurations. The damage progression in a unidirectional layer is assumed to be governed by the strain-rate-dependent layer progressive failure model using the continuum damage mechanics approach. The composite failure model has been successfully implemented within LS-DYNA® as a user-defined material subroutine. In this paper, the ballistic limit velocity (V50) was first established for a series of laminates by ballistic impact testing. Correlation of the predicted and measured V50 values has been conducted to validate the accuracy of the ballistic modeling approach for the selected carbon composite material. A series of close-in shock hole blast tests on carbon composite panels were then tested and simulated using the LS-DYNA® Arbitrary-Lagrangian-Eulerian (ALE) method integrated with the Army Research Laboratory (ARL) progressive failure composite model. The computational constitutive model has been validated to characterize the progressive failure behavior in carbon laminates subjected to close-in blast loading conditions with reasonable accuracy. The availability of this modeling tool will greatly facilitate the development of carbon composite structures with enhanced ballistic impact and blast survivability.


2006 ◽  
Vol 306-308 ◽  
pp. 285-290
Author(s):  
Young Shin Lee ◽  
Hyun Soo Kim ◽  
Young Jin Choi ◽  
Jae Hoon Kim

The laminated composite structures applied to the wing and the speed brake of an aircraft or the turbine blade of a compressor. These structures may be impacted by birds and hails during operation. They may also be impacted by drop of a tool during manufacture or repair. Unlike high velocity impact damage, which can be easily found by the naked eye, the damage due to low velocity impact may be difficult to detect. Damage which is not detected may cause failure of a structure and result in damage propagation. Growth of damage means reduction of stiffness on the structure. So, exact prediction of damage caused by a low velocity impact is very important in order to guard against sudden failure of the structure. In this study, modified delamination failure criterion has suggested in order to predict the failure behavior of a composite plate subjected to low-velocity impact. The criterion includes the assumption which is matrix cracking mode causes delamination failure. Predicted damage using supposed delamination criterion is similar to experiment results.


2013 ◽  
Vol 594-595 ◽  
pp. 707-710
Author(s):  
A.A. Arifin ◽  
A. Othman

In this paper presents the effect of energy absorption on thin-walled aluminum cross-section square tubes wrapped with woven E-glass fiber laminated composite subjected to quasi-static axial compression. The compression test was carried out experimentally to examine the amount of energy can be absorbed as well as to observe for failure behavior for each specimens. The wall-thicknesses aluminum square of 1.9 mm was investigated and woven E-glass fiber laminate reinforced polyester resin was examined. Two different numbers of layers woven E-glass were investigated and examined. Result obtained from experimental analysis such that initial peak load, mean load, quasi-static absorbed energy against displacement curves were recoded and plotted then compared for each specimen profile. Results indicated that the tubes crashworthy structure was affected significantly by different number of layers wrapped on wall aluminum square profile and also that the effect of crushing behaviors and failure modes was discussed.


Author(s):  
Y Narita ◽  
G J Turvey

Research on optimum lay-ups and buckling loads of laminated plates is briefly reviewed. A new sequential, iterative procedure, known as layerwise optimization (LO), for determining the optimum lay-ups and maximum buckling loads of symmetrically laminated rectangular plates is described. The physical basis of the procedure is explained. LO is shown to be highly efficient, with reductions in computational effort of more than 99 per cent being possible in comparison to some simultaneous optimization procedures. Three examples are presented of the use of the LO procedure to determine the optimum lay-ups and associated maximum buckling loads of 8- and 24-layer symmetrically laminated rectangular plates subjected to uniform, uniaxial and biaxial compression. For 18 combinations of free, simply supported and clamped edge conditions, it is shown that the LO procedure generally leads to the optimum solution. In the very few instances where a local rather than a global solution was obtained, the maximum buckling load was only 4–6.5 per cent lower than the optimum value.


2008 ◽  
Vol 82 (2) ◽  
pp. 225-234 ◽  
Author(s):  
Ramazan Karakuzu ◽  
Cihan Rıza Çalışkan ◽  
Mehmet Aktaş ◽  
Bülent Murat İçten

2012 ◽  
Vol 706-709 ◽  
pp. 799-804 ◽  
Author(s):  
Takashi Yokoyama

The impact compressive failure behavior of a unidirectional T700/2521 carbon/epoxy laminated composite in three principal material directions or fiber (1-), in-plane transverse (2-) and through-thickness (3-) directions is investigated on the conventional split Hopkinson pressure bar (SHPB). Cubic and rectangular block specimens with identical square cross section are machined from an about 10 mm thick composite laminate. The uniaxial compressive stress-strain curves up to failure at quasi-static and intermediate strain rates are measured on an Instron testing machine. It is shown that the ultimate compressive strength and strain exhibit no strain-rate effect in the 1-direction, but a slight strain-rate effect in the 2-and 3-direction over a range of strain rates from10-3to 103/s.


Sign in / Sign up

Export Citation Format

Share Document