TOPIC INCLUDES- STONE BRICK LIME

LIME The product obtained by calcination of lime stone is called lime Caco3------------on calcination co2+cao

Uses of lime: Used as binding material in mortar for stoneware. Used as plastering for interior surface of walls. Preparing concrete for foundation and flooring works. Knotting of timber work before painting. For stabilizing the soils. As a flux in manufacture of steel. Used for whitewashing the rooms of building. Hydraulic lime can be used for masonary work below ground level.

IMPORTANT TECHNICAL TERMS Calcination The process of burning of lime stone to redness in contact with air is called calcination

Quick Lime Lump lime Fat lime The lime obtained by calcination pure lime stone is quick lime. Lump lime The quick lime as it comes from klin is called lump lime. Fat lime The lime having high caicium oxide content is called fat ,rich or white lime.

Hydrated lime a dry power is obtained by treating quick lime with water just to convert lime into calcium hydroxide is called hydrated lime PUTTY A plastic mass of lime which resuits from the slaked lime in presence of water is putty

Slaking of lime Milk of lime When quick lime is treated with water,the process is called slaking of lime associated with sound of hissing noise, cracking sound ,slight explosion and evolution if heat and steam. Milk of lime A thin pourable suspension of slacked lime in water is called milk of lime

Setting The hardening of lime after it is made in to paste with water is called setting. Hydraulicity The property by virtue of which the lime or cement sets under water or in positions is called hydraulicity

NATURAL SOURCES OF THE MANUFACTURE OF LIME Lime stone- pure form quarried from rocks Boulders of lime stone from the bed of rivers,nallahs etc. Kankar found below the ground which are greyish in colour and impure form of lime stone. Shells of sea animals –contains calcium carbonate.

Manufacture of lime Involves following operations: Collection of raw material. Transporation of raw material. Collection of fuel. Burning of lime stone. Slacking of lime stone.

Collection of raw material Pure lime stone which is available in almost all state of india. Kankar lime stone: This form contins 30% clay in form of allumina and silica. Nodular form: Available from hill side or on the the banks of rivers Block form: Solid deposite of lime stone. Other varieties-sea shells, coral lime, gypsum lime etc.

Transportation of raw material: By carts Trucks Rails Ropeway

Collection of fuel For calcination following fuel are used: Wood Coal Coke Coal gas Charcol Cinder Oil

Setting action of lime The process of hardening lime after it is made into a paste with water is called setting action of lime

Setting action of fat lime: It depends upon the extent to which it comes in contact with air from it derives carbon dioxide. It is a slow process, for this reason fat lime is used for plastering the walls mainly in interior walls

Setting action of hydraulic lime: Setting action of hydraulic lime is independent of presence of carbon-dioxide It depends upon the extent of quantity of water used ,therefore it is suitable for under water structures and plastreing external walls.

Storage of lime Quick lime should be stored soon,because it can readily absorb moisture from atmosphere and turns into orignal formof calcium carbonate It should be stored in dry bags in moisture proof room. Bags of lime should be kept 30 cm away from walls.

Pozzolanic materials The sillicious and aliminious mineral substances which do not possess cementitious propertities themselves,but form cementitious compounds by reacting lime in presenceof water are known as Pozzolanic materials

Properties of pozzolanic materials Do not possess cementitious properties themselves Increase hydraulic properties of lime mortar and concrete. Reduce shrinkage of the mortar and concrete Increase resistance to cracking of mortat and concrete

Improves workability of mortar and concrete. Lower the heat of hydration. Increase resistant of mortar to chemical attacks. Economical to use. Helps in early setting of mortar.

Uses Useful in mortars and concerte to used in hydraulic structures and structures exposed to sea waters and alkali soils.

Artificial pozzolanic materials Fly ash: Fly ash is obtained from residue of burning of coal in furnaces and locomotives in form of powder. It should cleaned thoroughly before use. Burnt clay: It is also term as surkhi.it is mostly used in making lime mortar to be used in joints of walls for plastering.