1. Near Term Timetable Homework 7: two FEM problems, posted
yesterday, due Th October 22.
RQ#5 on FEM on Tuesday Oct 20. Read Chapters (omit 16). Only basic questions.
Recitation next week on Friday Oct 23 will cover
beams by DF and FEM (two problems)
Midterm exam Friday Oct 29, announced in HW 7.

2. Returned Today Midterm Exam 2 and HW 5 have been
graded, may be picked up from table
Solutions for both are posted on the Web

3. ANSYS Demos for Computer Portion of Lab 2
To be held on Friday October 15, at Visions Lab
(ECAE 1B73) - No recitations that day.
To get access with your Buff Card and get an account,
register at the OIT site specified on the ANSYS tutorial.
Attendance recommended but not required
Demo is a hands-on, self-learning (individual) tutorial.
Once in, sit at any empty computer and try logging in
Using your Identikey and PW. T.A.s available to help.
Access to VL is 24/7, except if classes are being held

4. Demo Times Because of limited seating (physically 25 workstations)
the demo will be divided into four
roughly-one-hour subsections
Sec 011: 1 PM and 2 PM
Sec 012: 3 PM and 4 PM
Student distribution on next slide

5. Section 011 (1-3 PM) Splitting
A-L PM
M-Z PM
Section 012 (3-5 PM) Splitting
A-L PM
M-Z PM

6. No Grouping Necessary Note: members of a group need not
attend the same demo subsection,
since the tutorial is individual

7. A Short Pictorial Introduction to FEM

8. Before 1950, standard structural elements
such as beams, ribs and spars,
were sufficient for modeling
low aspect ratio aircraft
structures
(e.g. Lockheed Constellation,
pictured on left)

9. The modern FEM was developed ...
... starting about 1952 as a modeling tool to simulate delta wing military aircraft on digital computers
Digital computers began to be commercially sold by Only aerospace companies and some government agencies could afford them (a vacuum-tube monster weighting several tons and with the power of an iPhone cost the
equivalent of $100M today)

10. Most of the pre-1960 work was done at a few places

11. A key 1956 paper described the DSM as used today

12. The method was well on its way by 1960
... but it had a marketing problem:
no brand name

13. Name was coined by Ray Clough in 1960

14. Ray Clough’s early career I
b. 1921, Seattle
served in Air Force during WWII
Ph.D. Aero & Astro MIT, 1950
joined Civil Engrg faculty at UC Berkeley, 1951
avid mountaineer & skier (holds many climbing records)

15. Ray Clough’s early career II
spent summers at Boeing at Jon Turner’s group so he could go mountain climbing on weekends
modern FEM started by 1956 JAS paper by
Turner, Clough, Martin & Topp
back at Berkeley, became interesting in Civil
applications, especially earthquake engineering
formed FEM research group in 1958

16. First Civil structure analyzed by FEM (1962)

17. Ray with Kurt Gerstle (his 1st student) on left pic
2002
1956

18. Ray Clough’s late career
gave up FEM research in 1972 for earthquake engineering
head of NSF Earthquake Engineering Center
at Richmond, CA,
retired from Berkeley 1987
honored with National Medal of Science, 1994

19. An Unimpeachable Gentleman

20. Explosive Success ...
By 1970, FEM (DSM) had taken over computational mechanics and was expanding beyond structures
Some samples follow

23. F-16 Structural Model

24. F-16 Exterior Surface Zoom
95% of
elements are
HPSHEL3
18 DOF shells

25. F-16 Interior Structure Zoom
Some solid elements
(bricks & tets)
used for “wing fingers”

26. Liquid Natural Gas (LNG) Ship - Global FEM Model

27. Stepwise Construction of Global Model

28. “Hot Spots “ Detailed Local Models

29. Wave Motion and Hull Pressures

30. The Troll Platform 470 m high including superstructure
m3 of concrete
tons of steel reinforcement
Design life of 50 years
Largest man-made object ever moved
Supplies 10 percent of Europe’s gas consumption

31. The Heidrun Platform Floating TLP Platform Made of reinforced concrete
16 vertical anchoring lines (tethers)
of pre-tensioning
Transverse stiffness supplied by secondary geometric effects

32. Last But Not Least ...

33. 16-bay Truss for Lab #2: FEM Model (Mathematica)

34. Idealization Process

35. FEM-DSM Breakdown

36. FEM-DSM Assembly & Solution

37. The Example Truss

38. The Truss Example