Civil Engineering Department

CE 501

Fall Semester 2003-04 (031)

Homework # 4

1) Discuss the importance of aggregate in concrete with respect to economy.

2) Explain the influence of aggregate properties on the properties of concrete.

3) Explain the effect of shape and texture of aggregates on concrete workability.

4) What is the importance of sieve analysis and how is the aggregate maximum size determined.

5) a- What is the importance of the Fineness Modulus?

b- Determine the F.M for the following aggregates:

Sieve Size #4 8 16 30 50 100 200 pan

Weight retained 0 41.2 84. 92. 129.8 80. 10.0 3.0

Sample weight is 450 g.

6) Explain why pozzolan reduces alkali-silica reaction.

7) Alkali cement content expressed on Na₂O equivalency, explain.