Jingxi Liu

On resistance of a rectangular thin plate under lateral indentation by a wedge indenter

ABSTRACT This paper addresses a study on the resistance of a clamped rectangular plate quasi-statically punched at the mid-span by a rigid indenter with a knife and a flat edge shape, through simplified analytical method. A new membrane stretching pattern is proposed and the resistancepenetration response is obtained. To validate this analytical method, a series of quasi-static tests on specimens with three lengthwidth ratios and indenters with six different scantlings are conducted. The well-matching of the resistance–penetration curves from analytical calculations and those from experiments proves the validity of the proposed simplified analytical method. Based on the analytical method, the influences of the indenter size and the plate scantlings on the resistance are evaluated. Moreover, the analytical method proposed in this paper is proved to be able to predict the quasi-static response for a wide range of plate lengthwidth ratios as well as to forecast low-velocity impact dynamic responses.

Two-Dimensional Crack Growth Simulation under Mixed-Mode Loading

In this paper, an efficient simulation program (FCG-System) is proposed to simulate 2D fatigue crack growth under mixed-mode loading conditions. The simulation is basically an incremental crack extension procedure. An object-oriented modeling frame is proposed for simulating fatigue crack growth of complex structures. The modeling frame is developed in the context of the commercial FE code ABAQUS, utilizing Python language and ABAQUS Scripting Interface (ASI). The highly automatic finite element simulation method is not only used for a single crack tip, but also has been extended to the system of interactive multiple cracks. The robustness and the accuracy of the new simulation code will be shown by two examples, including single crack growth and multiple cracks growth. Those applications indicate that the implementation of the FCG-System, as proposed herein, can be a useful tool for this class of fatigue crack growth.

Study on Vibrational Power Flow Propagation Characteristics in a Laminated Composite Cylindrical Shell Filled with Fluid

The characteristics of vibrational power flow in an infinite laminated composite cylindrical shell filled with fluid excited by a circumferential line cosine harmonic force are investigated using wave propagation approach. The harmonic motions of the shell and the fluid filled in the shell are described by Love shell theory and acoustic wave equation, respectively. Under the driving force, the vibrational power flow input into the coupled system and the transmission of the power flow carried by different internal forces (moments) of the shell in the axial direction are established. Numerical computations are implemented to investigate the vibrational power flow input and its propagation. It is found that characteristics of the vibrational power flow vary with different circumferential mode orders and frequencies, and the presence of fluid in the shell significantly affects the vibration of the shell structure. Additionally, parametric investigations are carried out to study the effects of the fiber orientation, modulus ratio , and thickness-to-radius parameter on input power into the coupled system and propagation power along the shell axial direction. This work will provide some guidance for the vibration control of the laminated composite cylindrical shell.