Building Materials, Third Edition

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The workers must be provided with goggles and respirators against high heat and dust
generated during slaking. Skin protecting cream must be applied as protection against skin-
burn.

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A comparison of the binding materials, cement and lime is presented in Table 8.3.

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1. Explain the terms
   (a) Poor lime (b) Fat lime
   (c) Hydraulic lime (d) Quick lime
   (e) Slaked lime (f) Punning


2. (a) Describe the different varieties of lime.
   (b) Why is it necessary to slake quick lime immediately after burning?
   (c) Why is hydraulic lime unsuitable for plastering?


3. Describe briefly how lime is manufactured. Distinguish between quick, fat and hydraulic
   lime.


4. (a) How is hydraulic lime classified?
   (b) State the effects of impurities present in the lime.
   (c) What is lime putty and how is it prepared?


5. (a) Describe the method of burning lime.
   (b) How is the lime slaked? What is the significance of slaking lime?
   (c) Explain briefly the setting of lime.


6. (a) What are the characteristics of lime?
   (b) State teh harmful effects of silica, sulphates and alkalis in lime.
   (c) How is lime classified according IS specifications?


7. Briefly describe hardening of lime. How is hydrate hardening of lime different from
   hydrosilicate hardening.