scholarly journals Elastic Responses of a Composite Shell Structure Subjected to Impact Loading

2021 ◽  
Author(s):  
Shiuh-Chuan HER ◽  
Ching-Chun LIAO

Received 17 December 2019; accepted 17 June 2020 This work investigated the elastic responses of a composite laminate shell subjected to a transverse low-velocity impact. The governing equation based on the equations of motion of both the impactor and target was developed to detetrmine the impact force. The displacement of the shell subjected to unit impulse loading was solved using the finite element method. A non-linear differential equation in terms of the indentation depth was derived by incorporating the Hertzian contact law and theory of convolution. Runge-Kutta method was employed to solve the non-linear integro-differential equation, leading to the determination of the impact force at the point of contact between the impactor and the composite shell. The elastic responses including the displacement and stress of the composite laminate shell were evaluated using the finite element method by exerting the impact force on the apex of the composite shell. Present approach was verified with the analytical, experimental and numerical results reported in the existing literatures. The influences of stacking sequence of the composite laminate shell on the impact responses were examined through a series of parametric studies. In addition, impact responses of the spherical shells with different materials such as steel, aluminum and glass were studied.

2015 ◽  
Vol 1120-1121 ◽  
pp. 590-592
Author(s):  
Hyoh Yun Choi ◽  
Yeon Jun Lim ◽  
Hyun Jun Cho ◽  
Hyun Bum Park

In this work, study on impact damage FEM model of composite structure was performed. From the finite element method analysis results of composite laminate, it was confirmed that the results of analysis was reasonable. The velocity of impactor to initiate damage was estimated, and in order to investigate the damage at the predicted velocity, impact analysis using finite element method was performed. According to the impact analysis results of composite laminate, it was confirmed that the damage was generated at the estimated impact velocity. Finally, the comparison of the numerical results with those measured by the experiment showed good agreement.


2018 ◽  
Vol 934 ◽  
pp. 24-29
Author(s):  
Prapasiri Pongprayoon ◽  
Attaphon Chaimanatsakun

Graphene nanopore has been widely employed in nanofilter or nanopore devices due to its outstanding properties. The understanding of its mechanical properties at nanoscale is crucial for device improvement. In this work, the mechanical properties of graphene nanopore is thus investigated using atomistic finite element method (AFEM). Four graphene models with different pore shapes (circular (CR), horizontal rectangle (RH), and vertical rectangle (RV)) in sub-nm size which could be successfully fabricated experimentally have been studied here. The force normal to a pore surface is applied to mimic the impact force due to a fluid flow. Increasing pore size results in the reduction in its strength. Comparing among different pore shapes with comparable sizes, the order of pore strength is CR>RH>RV>SQ. In addition, we observe that the direction of pore alignment and geometries of pore edge also play a key role in mechanical strength of nanopores.


2018 ◽  
Vol 196 ◽  
pp. 01055
Author(s):  
Sławomir Dudziak ◽  
Zofia Kozyra

Dynamic analyses play an important role in the process of designing buildings in the vicinity of transportation routes. The Finite Element Method is the most popular modelling technique, because it allows to simulate the structure response in the higher frequency range properly. However, the results of such analyses depend on many factors and can differ a lot. This paper discusses the impact of the building mass estimation and neglecting or including damping in the analysis on the assessment of influence of vibrations due to traffic on people.


2011 ◽  
Vol 2011 ◽  
pp. 1-10
Author(s):  
Yi Wang ◽  
Nai Xian Hou ◽  
Zhu Feng Yue

The experiments and finite element simulations of composite laminate with stitching are carried out. Firstly, the monotonous tensile experiments with and without stitching are conducted to investigate the influence of stitch reinforcement on the composite laminate. Secondly, the finite element method (FEM) is employed to simulate the tensile process of specimens, and the link element is introduced to simulate the stitching. The experiment results shows that the stitching has little influence on the damage load under monotonous tensile load, while there is a significant influence on the changing of strain. The FEM results are consistent with the experiment results, which means that the link element can be used to study the stitching of the composite laminate. The simulation results also show that the distributions of strain are changed obviously due to the existence of the stitching. Research results have a significant role on the design of the composite structures with and without stitching.


2012 ◽  
Vol 190-191 ◽  
pp. 23-27
Author(s):  
Jin Sha ◽  
Zhi Yuan Yao ◽  
Yang Jiao

This paper proposes an ultrasonic knife system for MEMS packaging. The ultrasonic knife system is consisted of an ultrasonic transducer, a cutter and a gripper feeder. The ultrasonic transducer engenders high frequency vibration, which lead to the resonance of the structure. Amplitude transformer can magnify the amplitude. By the impact and collision of the cutter, the material can be cut through, and the high temperature created by high-frequency vibration can do the welding. The structure is designed and optimized by the finite element method, and a model machine is produced. According to the experimental results, the ultrasonic knife system has the virtues of high cutting force and better wedding feature, which are suitable for MEMS packaging.


2009 ◽  
Vol 294 ◽  
pp. 27-38 ◽  
Author(s):  
Fabian Ferrano ◽  
Marco Speich ◽  
Wolfgang Rimkus ◽  
Markus Merkel ◽  
Andreas Öchsner

This paper investigates the mechanical properties of a new type of hollow sphere structure. For this new type, the sphere shell is perforated by several holes in order to open up the inner sphere volume and surface. The mechanical behaviour of perforated sphere structures under large deformations and strains in a primitive cubic arrangement is numerically evaluated by using the finite element method for different hole diameters and different joining techniques.


2012 ◽  
Vol 594-597 ◽  
pp. 387-390
Author(s):  
Yu Hu ◽  
Qiang Feng

With the saturated - unsaturated seepage theory, Hualianshu landslide is seepage numerical simulated by the finite element method .The changes of Hualianshu landslide seepage are subject to the impact of rainfall and reservoir water level's changes.The formation and variation of the slope seepage field under rainfall infiltration have been come to, providing a basis for analysis of slope stability and landslide prediction.


2013 ◽  
Vol 368-370 ◽  
pp. 756-759
Author(s):  
Jing Ma ◽  
Wen Sheng Chen ◽  
Xue Feng Hu

Based on the Finite Element Method ,a model has been built to study the impact of rigid pile composite foundation with lateral unloading,then obtained a conclusion about the horizontal displacement during excavating.


2014 ◽  
Vol 1078 ◽  
pp. 201-205
Author(s):  
Teng Fei Wang ◽  
Peng Lan ◽  
Nian Li Lu

The analysis model is built to investigate the out-of-plane stability of crane jib with auxiliary bracing. Considering the second-order effect, the analytical expression of the out-of-plane buckling characteristic equation for the crane jib with auxiliary bracing is obtained by establishing the bending deflection differential equation of jib under the instability critical state with the method of differential equation. The equilibrium equation of the cable converging point in the lateral direction is introduced to solve the differential equation besides the boundary conditions and deformation compatibility equations. With the characteristic equation, the critical compression or the critical lifting load can be easily obtained. The characteristic equation is analytically expressed and the analytical results obtained agree very well with the finite element method (FEM) results. The validity of the characteristic equation is verified.


Sign in / Sign up

Export Citation Format

Share Document