The limestone are tested to determine the quality of lime which can be obtained from them. For determining exactly the suitability of limestone, the detailed chemical tests are carried out in a laboratory. But for general information, the following four practical tests are made:
(1) Physical properties
(2) Heat test
(3) Acid test
4) Ball test.
(1) Physical properties: The pure limestone is indicated by white colour the hydraulic limestone are indicated by bluish grey, brown or some dark colour the taste of hydraulic limestoneâs is clayey and they give out earthy smell. The presence of glistering particles on the surface of limestone indicates the presence of free sand. The presence of lumps gives an indication of quick lime or unburnt limestone.(2) Heat test: A piece of dry limestone is weighed and it is heated in an open fire for few hours the sample is weighed again and loss of weight indicates the amount of carbon dioxide, From this data, the amount of calcium carbonate in limestone is worked out. (3) Acid test: A teaspoon of powdered lime is taken in a test tube and dilute hydrochloric acid is poured in it. The contents now stirred and the test tube with its contents is then kept standing in its stand for 24 hours.
If a thick jell or semi-solid material is formed which does not flow even when the test tube with its contents is turned upside down, it indicates lime of class A. If the jell is not quite thick and tends to flow when the test tube is tilted, it indicates lime of class H If however there is no jel formation, it indicates lime of class G.(4) Ball test: In this test, the bails of about 40 mm size of stiff lime formed by adding enough water are made and they are left undisturbed for six hours. The balls are then placed in a basin of water. If there are signs of slow expansion and slow disintegration within minutes after placing in water, it indicates class C lime. If, on the other hand, there are very lite or no expansion and numerous cracks, it indicates class B lime.
PD Consulting Engineers Pvt. Ltd. Transforming construction for a new generation "Cost, Quality & Project management"
QS & Cost management, Bill Checking / Audit, Technical Auditors, Valuation, Contract and Tendering, Project Management, Project Planning, Quality Control, Consulting Engineers, Structural Consultancy
Civil N Construction Blog