Brief explanation/case study of my career, presented to students at the Hockaday School in Dallas, Texas

1. “ ask the structure.” Hockaday Career Day By Amy Barr, EIT, Hockaday ‘00

3. I’m a structural forensics engineer. I work for Wiss Janney Elstner, a company that investigates the situation whenever structures have problems. What do I do?

4. What do you mean by “problems”?

5. Tennessee River State Route 69 Bridge BRIDGE COLLAPSE

6. New Orleans Warehouse WAREHOUSE FIRE

7. Earthquake - Turkey WORLD SEISMIC EVALUATION AND DAMAGE EVALUATION

12. Two Unique Interview Questions: 1) Are you afraid of heights?

13. A Member of the WJE Difficult Access Team

14. 2) Are you afraid of enclosed spaces?

24. If there is a career out there that you want to pursue, you just have to decide to pursue it and work hard. It is yours for the taking. Hockaday grads can do ANYTHING.

29. Packing List All of that equipment is really secondary to our engineering common sense.

31. So… Take physics and calculus and chemistry, and keep your eyes open.

33. Photos sent via e-mail by your client, the NC Department of Transportation

34. Photos sent via e-mail by your client, the NC Department of Transportation

35. What could possibly have caused this?

37. Before After

39. This is a double-tee beam.

42. What is prestressing, and why do we do it? Material Properties!

44. Look at a beam…

49. Steel is Stronger Steel is much stronger in tension, and so the fact you can’t break a steel bar like you can break a concrete block is because of the tension strength of steel. The bottom of the steel bar would not break, whereas when he put the bottom of the bar of concrete in tension, it broke relatively easily.

50. How do we get a good, cheap construction material? It’d be great if we could take the average of the two…

52. SIDE VIEW END VIEW

53. How do we get the most use out of these steel strands? It’s called “prestressing”. We use steel as though it were a rubber band.

59. How do we make prestressed beams?

60. Making Prestressed Beams

61. Making Prestressed Beams

62. Making Prestressed Beams

63. Making Prestressed Beams

64. Making Prestressed Beams

65. Making Prestressed Beams Tindall uses a quick-curing grout with calcium chloride in it.

66. So, what happened?

68. What is it? What do you notice about it? Sifting through the concrete, you find this…

70. What caused it to rust like that? (Remember that quick-curing grout that Tindall used to patch the pushdown hole?)

71. A bit about rust

72. A Few Weeks Later