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The code name for the developed application is Helium. The relevance of the name Helium is that Helium's atom is the simplest atom that cannot be solved using an exact analytical mathematical approach. Instead numerical mathematical methods are employed for solving even a simple atom consisting of one nucleus and two electrons. I remain indebted to my supervisor Prof. Harm Askes (Head of Department, Civil Engineering, University of Sheffield) for all his guidance and support throughout the project.
Failure of an engineering material is almost always not a desirable event. One of the modes of failure of materials is through cracking of the material. It is possible simulate material failure using finite element analysis. In fact one of the very first applications of finite element analysis was analysis of structures. In this dissertation finite element method was utilized to simulate material failure.
The dissertation can broadly be divided in two phases. In the first phase, a computer application incorporating finite element analysis was developed using MatLab. The developed application simulates a simple beam structure by generating a finite element lattice model made up of finite bar elements. The capability of simulating material heterogeneity was incorporated in the program to simulate materials like concrete. Dynamic analysis of the structure can be performed by the program using implicit direct integration Newmark constant average acceleration method. Stress patterns in the beam material are also generated simulating material failure. In the second phase of the dissertation a number of analyses were carried out using the application. These tests were designed keeping in view the basic hypothesis of the dissertation: possibility of modelling static tests using dynamic implementation. The general procedure for carrying out the tests was to change a single parameter at one time to find out the effect of changing that parameter. The results from the analyses performed not only delivered answers to the basic hypothesis but also verified the functionality of the application developed.
It was concluded from the results obtained from the analyses that it is possible to model static tests using dynamic implementation provided the there is a gradual increase in the dynamic load that is applied to the structure. It was also concluded that heterogeneity of material may not influence the global structural behaviour like reaction forces or displacements but does have local effects like cracking of interfaces between aggregate and cement sand matrix.
A number of options are defined in the application for generating and saving outputs of the application. The application can plot time histories or displacement, velocity, acceleration and reaction forces. It also captures the stress distribution figures of the analysis at each time step. These screen captures are saved in enhanced meta file (emf) format. A movie is also generated in AVI file format of the complete analysis. All the variables generated during the analysis are also stored in a MatLab file which is useful for further analysis of a specific test.
A sample animation generated automatically by the application for a simply supported concrete beam with dynamic loading at the centre can be viewed in the video below:
A sample screen capture displaying the stress pattern generated automatically by the application at a particular instant of the dynamic analysis of a simply supported concrete beam is displayed (click to enlarge) below:
The application also generated time histories for displacement, velocity and acceleration at different locations specified by the user. A sample of these time history graphs generated automatically for each analysis is displayed in the picture (click to enlarge) below:
If you require any further information regarding the project you can contact me.