User:Eml4500.f08/HW report table/The best of HW5

 Under construction; not final (but close to being stable after a couple of weeks). The intention here is to document the best features in any HW report for the readers (including you); if you see excellent features in any HW report (including your team's) that I may have missed noticing, don't hesitate to let me know. I don't have time to read all HW reports in detail. In fact, due to time constraint, I only selectively looked at a few important features. On the other hand, I also added some annotations (e.g., related to errors) in the HW reports that I looked through for the benefit of everyone. Eml4500.f08 11:11, 10 November 2008 (UTC)


 * classnotes graded over 100%
 * principle of virtual work (PVW) continued
 * 2-bar truss: elimination of rows to obtain reduced system, formal derivation
 * 2-D bar element (Lecture):
 * axial FD relation: equivalence with PVW, formal derivation
 * general 2-D FD relation: formal derivation by PVW
 * transformation from element global dofs to element axial dofs; similarly for element global force components to element axial force components
 * PVW for axial FD relation; transformation of weighting coefficients from axial coordinates to global coordinates; transformation of axial dofs to global dofs; FD relation in global dofs for 2-D bar element
 * 3-D bar element (HW): derivation of FD relation and element stiffness matrix by PVW, similar to 2-D bar element above. Best presentation: Team ATeam(Sean) even though the details of the matrix multiplication for the final expression for $$\displaystyle \mathbf k ^{(e)}$$ were not provided; see Team Bike, but there was an error in the derivation concerning the use of the PVW. NOTE: Team Delta_6 (with annotations) Team Jamama (with annotations) did not do this part.  Team Bike (with annotations).
 * axial FD relation: equivalence with PVW, formal derivation
 * general 3-D FD relation: formal derivation by PVW
 * transformation from element global dofs to element axial dofs; similarly for element global force components to element axial force components
 * PVW for axial FD relation; transformation of weighting coefficients from axial coordinates to global coordinates; transformation of axial dofs to global dofs; FD relation in global dofs for 3-D bar element
 * continuous system governed by partial differential equations (PDEs)
 * model problem: elastodynamics of a bar with varying cross section and varying Young's modulus, subjected to arbitrary time-dependent loads
 * free-body diagram of infinitesimal element, derivation of PDE of motion
 * boundary conditions: clamped-clamped case, clamped-free case (with distributed load and a concentrated load at the free end)
 * initial conditions: initial displacement, initial velocity

EAS 4200C, The best of HW5
 * matlab problem graded over 100%
 * 2-D truss:
 * two-bar truss: debug, display "results" array, compare to statics solution. Best solution: Team ATeam(Sean), Team Bike, Perfect, nice problem description with figure and table of element properties, clear description of the bug in previous matlab code, presented "results" array in wiki table form, static solution for reactions, comparison with FE solution for element strains, stresses, forces.  Team Wiki1 (with annotations) also did excellent work, except that they used the incomplete matlab function PlaneTrussResults displayed in Team Delta_6 HW2 Fixed (with annotations), where the last line of the code was missing; Team Wiki1 modified the matlab code to make it work due to this missing last line.  NOTE: If you were not careful, and simply copied the incomplete matlab function PlaneTrussResults from the wiki page Team Delta_6 HW2 Fixed (with annotations), you would get only the first column (containing the strains) in the 2x3 array "results", and would unlikely be able to relate these results to the element forces obtained using statics as they did not represent the element forces (but the element strains); see Team Gravy (with annotations)
 * six-bar truss: same Young's modulus E and cross-sectional area A
 * six-bar truss: Different Young's moduli E and same cross-sectional area A
 * 3-D truss with 3 bars: Best solution: Team ATeam(Sean), Team Bike, Team Wiki1 (with annotations)
 * analysis with FE code
 * computation of reactions
 * plots of underformed and deformed shapes
 * static solution; computation of reactions
 * comparison of reactions obtained from FE and from statics