Concrete Final Exam QUESTIONS AND ANSWERS RATED A+ 2023|2024 UPDATE

Concrete Final Exam QUESTIONS AND ANSWERS RATED A+ 2023|2024 UPDATE 1. Prior to placing concrete for pavements or slabs on grade, what should be done?: Ans- Subgrade should be compacted, trimmed, and moistened; forms should beerected; and the reinforcing steel members should be securely in place. 2. In hot weather, what is important to do to the subgrade?: Ans- It needs to bemoistened to prevent the dry ground from sucking water out of the concrete. 3. What is true about forms for concrete?: Ans- Wood forms should be moistened to prevent water loss from the concrete, all forms should be able to be removed fromthe concrete without damaging it. Steel should be clean and free of rust, steel formscan be below freezing when concrete is poured. 4. How should concrete be deposited?: Ans- Continuously as near as possible to itsfinal position. 5. How do you deposit concrete on a slab pour?: Ans- It should be started 2 / 7 along theperimeter at one end of the slab, the concrete should not be dumped in separate areas and spread out. 6. How should concrete be placed in walls, thick slabs, or foundations?: Ans- In horizontal layers of uniform thickness, each layer should be consolidated before thenext layer is added. 7. How rapidly should concrete be placed when pouring in layers?: Ans- Fastenough to not let the previous layer set. 8. How is concrete moved to lower elevations?: Ans- Chutes and drop chutes are usedto prevent segregation of the concrete. 9. How far can you drop concrete without segregation?: 50 feet 10. What is placed at the end of a chute to control the flow of concrete onto sloped surfaces?: A baffle 11. How thick should the layers of freshly mixed concrete be?: 6 inches to 20 inches thick for reinforced members, and 15 inches to 20 inches thick for mass work. 12. What determines the thickness of a layer of concrete?: Width between forms and the amount of reinforcement. 13. Should concrete be moved horizontally?: No, this causes segregation. If it has to be done it should be kept to a minimum. 14. What should be done if pouring concrete in an area where standing water