True false 3 the impact of water impurities is

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(True-------- False----------)
3- The impact of water impurities is dependent on the type of cement used,concentration of impurities and temperature. (True-------- False----------)4- The quality of water, used in concrete mixes, shall not cause change in thesetting time of more than 25% nor a reduction in compressive strength at 14days more than 5%. (True----False----------)
6- Air entraining admixtures may be used to improve the resistance ofconcrete to freezing and thawing. (True----- False------)7- Fly ash mixes require more water than plain concrete (True----- False------)8- Retarders are mostly used in Cold weather concreting activities (True-----False------)9- Admixture could be added to concrete in dry or liquid forms (True-----False------) B: ESSAY QUESTIONSSOLVE 3QUESTIONS ONLY1.Describe the impact of air entraining agents on the strength of concrete 2.Can we use see water in concrete mixes, explain ? 3.Define admixtures and list their major classes. 4.List one application for water reducing agents.5.Describe the impact of Pozzolans on the strength of concrete?4
PART II: ESSAY QUESTIONSSOLVE 7QUESTIONS ONLY 1.List the major components of concrete.2.What the purpose of the paste in concrete.5
3.What the name of the test that is used to measure the workability ofconcrete mixes.4.What is meant by the hydration process.5.List two factors that impact the hydration process.6.List three properties of GOOD concrete.7.List three factors that impact the workability of concrete.8.What are the two major elements of workability. Explain, briefly, thedifference between them.9.Define segregation and list two problems that it may cause.10.Define bleeding and list two problems that it may cause.11.List one use for Type III and type V cement, respectively12.List one use for white portland cement and expansive cement,respectively.13.List two properties of Portland cement.

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