Building Materials, Third Edition

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1. (a) What are different types of aggregates for making mortar and concrete?
   (b) What are the sources of fine aggregate? Give the characteristics and uses of sand.
   (c) What is bulking of sand? How does it affect concrete mix?


2. (a) What is fineness? How would you find the Fineness modulus value of coarse and fine
   aggregates?
   (b) What are the specifications of good sand for general use in buildings? From which
   source is sand preferred and why?


3. (a) What are the different sources of sand? which one of them is the best?
   (b) State the disadvantages of sea sand.
   (c) What is meant by aggregate? Briefly describe their classification.


4. (a) Discuss the characteristics of good aggregates.
   (b) What are the deleterious substances in aggregates? What are their harmful effects?


5. What is alkali-aggregate reaction? What are the factors which affect this reaction? How can
   this reaction be controlled?


6. Briefly describe the following tests:
   (a) Specific gravity test (b) Crushing test
   (c) Impact test (d) Ten per cent fines test


7. (a) What is the purpose of adding sand to cement mortar?
   (b) What is meant by all-in aggregate?
   (c) Write the general specifications for sand to be used in reinforced cement concrete
   works.


8. Briefly describe the following tests:
   (a) Deleterious materials (b) Organic impurities
   (c) Soundness (d) Fineness modulus


9. How do you determine fineness modulus of sand? What is its significance?


10. Write short notes on:
    (a) Effect of moisture on aggregates
    (b) Properties of good coarse aggregate
    (c) Fineness modulus
    (d) Alkali-aggregate reaction.

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1. Which of the following aggregates gives maximum strength in concrete?
   (a) Rounded aggregate (b) Elongated aggregate
   (c) Flaky aggregate (d) Cubical aggregate


2. The maximum bulking of sand is likely to occur at a moisture content of
   (a) 5% (b) 8% (c) 11% (d) 14%


3. Match List-I (Property) with List-II (Characteristic) and select the correct answer using
   the codes given below the lists:
   List-I List-II
   (Property) (Characteristic)
   A. Specific heat of an aggregate 1. Breaks the bond between the
   aggregate and the paste