Q1. What are the applications of portland cement types IA, III, and IV? Give an example of a project for each of them for which you would consider the use of these cement types. Explain the circumstances of the project examples you provide. (1.5 points)
Q2. What are the applications of the following admixtures? a) water-reducing, b) retarding, c) air-entraining. Give an example of a project for each of them for which you would consider the use of these admixtures. Explain the circumstances of the project examples you provide. (1.5 points)
Q3. What are the applications of the following formwork types? a) ganged, b) flying. Give an example of a project for each of them for which you would consider the use of these formwork types. Explain the circumstances of the project examples you provide. (1 point)
Q4. Answer the following questions regarding the concrete reinforcement. a) Why does concrete need reinforcement? b) Consider a structural beam made of unreinforced concrete, as seen below. If you apply an excessive vertical load, where do you expect to see the concrete crack first? (1 point)
Q5. Assume you will place concrete in a beam formwork with very tightly placed rebars. Answer the following questions based on the information provided. (2 points)
a) You decide to add more water to the concrete (increase the water to cement ratio) to increase its workability (higher slump) to make sure concrete can easily go through the tight spaces between the rebars. How will adding water adversely affect the concrete properties? What could you do instead of adding water to prevent this adverse effect while increasing the workability?
b) The structural plans show ten #8 bars at the bottom of the beam, which is difficult to layout in the formwork space provided and assure that concrete will easily fill out the space between the rebars. You suggest using #9 rebars. How many #9 rebars will be needed to equal the same total cross-sectional area?
Q6. You are planning for a deck’s concrete pour. The concrete volume is estimated to be 12,000 cubic yards. You have divided the deck into six sections for concrete placing. The concrete pour will happen simultaneously in all sections. Each section will have one boom pumper. Each boom pumper will be able to pump 100 cubic yards per hour at the designated section. (a) How many concrete trucks with a capacity of 10 cubic yards will you need? Consider a waste factor of 2% (b) How long will the concrete pour take? (1.5 points)
Q7. What are the differences between the pre-tensioned and post-tensioned concrete? (1 point)