Objective

For determination of soundness of Build lime by Le-chatelier method 

Reference Standards

IS : 6932(Part IX)-1973-Method of tests for Building Lime (Determination of soundness).

Equipment & Apparatus

• Le-Chatelier apparatus
• Steam boiler 

Preparation of sample

1. A suitable amount of hydrated lime is mixed with on third its mass of Portland cement and 4 times its mass of standard sand.
2. The ingredients is mixed dry and then gauged and mixed with 12% by mass of water calculated on the dry mixture.

Procedure 

1. Three ‘Le-Chatelier’ moulds is used for conducting the test. Each mould is placed upon a small non porous plate and filled with mortar under test, care being taken to keep the edge visibly open.
2. The mould is then covered with another non-porous plate, upon which a small weight is placed. The 3 moulds is left undisturbed for 1 hour.
3. After 1 hour the distance separating the indicator points is measured and these moulds transferred to a damp air cupboard for a period of 48 hours.
4. After 48 hours they are removed from the cupboard and placed in a steam boiler for a period of 3 hours. At the end of this period the moulds is removed from the steam and allowed to cool and the distance between the indicator points again measured 

Calculation: 

The difference between these two measurements indicates the expansion of lime.

Report

The mean of two values to the nearest 0.5 mm is calculated to represent the expansion of lime.

Safety & Precautions

• Use hand gloves while removing containers from oven after switching off the oven.
• Thoroughly clean & dry the container before testing.
• Petroleum jelly should be applied to the mould.
• Use apron & safety shoes at the time of testing.