Doctor of Philosophy (PHD)
Mechanical Engineering (Engineering)
Date of Defense
First Committee Member
Second Committee Member
Third Committee Member
Fourth Committee Member
Fifth Committee Member
James W. Giancaspro
A novel finite element capable of arbitrary cracking in solids under coupled thermo-mechanical loading has been formulated and implemented into the commercial software package ABAQUS as a user-defined element. The thermal-mechanical augmented finite element method (TM-AFEM) is an extension of the Augmented Finite Element Method (A-FEM) which includes temperature degrees of freedom (DoFs) so steady-state or transient temperature evolution and their direct effects on fracture processes in solids can be explicitly considered. The formulation incorporates a thermo-mechanical cohesive zone model (TM-CZM) to account for load and heat transfer across the intra-element weak and strong discontinuities (i.e. material interfaces and cracks). A novel condensing method is used to express the internal DoFs, both mechanical and thermal, as explicit functions of the external DoFs. It has been demonstrated through several numerical examples that, the TM-AFEM can provide a general framework for realistic simulation of thermal fracture problems both at single elemental level and at structural level. The advantages of the TM-AFEM include: (1) arbitrary crack initiation and propagation without a priori knowledge of the crack path; (2) greatly improved numerical efficiency as compared to similar advanced methods such as X-FEM or PNM because the TM-AFEM does not need extra external DoFs for crack evolution; and (3) the capability of accounting for multiple, complex crack evolution and interactions.
thermal fracture; thermoelasticity; FEM; simulation; thermal stress; arbitrary cracking
Do, Bao-Chan, "Extending the Novel A-FEM to Model Arbitrary Cracking in Thermo-elastic Solids" (2014). Open Access Dissertations. 1270.