3.1

The two-span bridge with a single central column support shown in Exhibit 3.1 is located in the vicinity of San Diego on an important strategic route. The soil profile at the site consists of a 35-foot layer of soft-to-medium clay.

Exhibit 3.1

1. The applicable acceleration coefficient, to be used for seismic design, is most nearly:

   1. 0.40

   2. 0.30

   3. 0.20

   4. 0.10

2. What importance classification should be assigned to the structure?

   1. I

   2. II

   3. Either I or II

   4. Insufficient information

3. What seismic performance category should be assigned to the structure?

   1. A

   2. B

   3. C

   4. D

4. The value of the site coefficient is most nearly:

   1. 1.1

   2. 1.2

   3. 1.3

   4. 1.5

5. What analysis procedure should be used?

   1. Procedure 1 or 2

   2. Procedure 3

   3. Procedure 1 or 3

   4. Insufficient information

6. The column has a moment of inertia of 40 feet ^[4] and a modulus of elasticity of 432,000 kips per square foot, and may be assumed fixed at the top and bottom. The stiffness of the column is most nearly:

   1. 12,970 kips per foot

   2. 13,070 kips per foot

   3. 13,170 kips per foot

   4. 13,270 kips per foot

7. The weight of the superstructure and tributary substructure has a constant value of 7 kips per foot. The fundamental period of the bridge in the longitudinal direction is most nearly:

   1. 0.34 seconds

   2. 0.34 seconds

   3. 0.36 seconds

   4. 0.37 seconds

8. The value of the elastic seismic response factor is most nearly:

   1. 0.8

   2. 1.0

   3. 1.2

   4. 1.3

9. The elastic seismic moment in the column due to the longitudinal seismic force is most...