Finite element analysis of vetiver grass composite structures | |
| Author | Fung, Ngo Cheng |
| Call Number | AIT Thesis no.ST-03-20 |
| Subject(s) | Finite element method Compositae Vetiver |
| Note | A thesis submitted in partial fulfillment of the requirements for the degree of Master of Engineering |
| Publisher | Asian Institute of Technology |
| Abstract | A mathematical framework has been introduced to investigate the behaviour of composite structures subject to incremental vertical loading. An analytical method has been described to predict the nine effective elastic moduli of an orthotropic composite bundle comprised of vetiver grass fibers and clay matrix. Both constituents are assumed to behave as isotropic linear elastic-brittle materials. These moduli are given in terms of the properties of both constituents as well as the cross-sectional aspect ratio and the volume fraction of the inclusions. A composite wall panel is made up of two different materials, namely vetiver grass composite bundles and clay paste joints arranged in a periodic way as a continuum. The vetiver grass composite bundles can be regarded as orthotropic elasticbrittle materials. For modelling the behaviour of wall panels, a two-stage homogenization procedure is used to obtain the average mechanical response of the composite wall panels. In the first step, composite bundles are homogenized with vertical joints to give equivalent elastic properties of a stacked system. Next, this stacked system is homogenized with horizontal joints to obtain equivalent material properties for the wall panels. This constitutive model can be incorporated into existing numerical packages to analyse vertically loaded wall panels. Three dimensional finite element analyses utilizing eightnoded solid elements are implemented in this study. The failure criterion based on the characteristic tensile strength of the composite bundles has been proposed to predict the compressive strength of wall panels. The results obtained from finite element analysis have been verified and validated with some limited experimental data, which showed a reasonable agreement. The finite element model can be used for predicting the behaviour of vetiver grass composite structures of arbitrary geometry and boundary conditions. A design of a single-story house based on this model is proposed. |
| Year | 2003 |
| Type | Thesis |
| School | School of Engineering and Technology (SET) |
| Department | Department of Civil and Infrastucture Engineering (DCIE) |
| Academic Program/FoS | Structural Engineering (STE) /Former Name = Structural Engineering and Construction (ST) |
| Chairperson(s) | Barry, William; |
| Examination Committee(s) | Pichai Nimityongskul;Kim, Kidu |
| Scholarship Donor(s) | Lee Foundation;Asian Institute of Technology-Partial Scholarship |
| Degree | Thesis (M.Eng.) - Asian Institute of Technology, 2003 |