STONE

GOVT ENG COLLAGE BIKANERPower point presentation on:- Building stoneSubmitted to :- Ankit sirSubmitted by :- Akshay kumar

Building stone @akshaykumar

STONEStone One of the oldest building material.

Rock : A large concreted mass of earthy or mineral matter or broken pieces of such a mass.

Stone : Quarried or smaller pieces of rock for a specified function such as a building block.

CLASSIFICATION OF STONESStones can be classified in following ways :1. Geological classification 2. Physical classification3. Chemical classification4. Classification based on stone hardness

GEOLOGICAL CLASSIFICATIONOn basis of hardness stone classified as:Igneous rocks: Formed by cooling and thus solidfying from a molten state. (Granite, Basalt)Sedimentary rocks : Formed by a process of cementation of small particles that result from the disintegration of rocks. (Limestone, sandstone)Metamorphic rocks : Formed by gradual changes in the structures of either igneous or sedimentary rocks caused by heat, water, pressure. (Marble, Slate)

PHYSICAL CLASSIFICATIONOn basis of hardness stone classified as:Stratified stones : Derived from sedimentary rocks . These stones are found in layers deposited one above the other.(limestone , sandstone) Unstratified stones : Do not show any type of layer formation.(granite , marble)Foliated stones : have tendency to split away in a definite direction only . This type of structure is commonly found in metamorphic rocks.

CHEMICAL CLASSIFICATION On basis of hardness stone classified as :Siliceous rocks : silica is principal constituent , hard & durable , not affected by weathering agencies. (granites , quartzites )Argillaceous rocks : clay predominates , moderately hard & durable but brittle.(slates , laterites )Calcareous rocks : calcium carbonate predominates.(limestone , marble )

HARDNESS CLASSIFICATIONOn basis of hardness stone classified as:As soft, medium, hard and very hard.Very hard rocks as Granite, Trap and Taconite.Hard rocks as Granite, Basalt, Gravel and Quartzite.Medium rocks as Dolomite and Lime Stone.Soft rocks as Talc, Gypsum and Sand stone.

USES OF STONE

Following are the various uses of stonesFor masonry work For lintels and vertical columns For covering floors of building For paving of roads and foot paths As a covering material for buildings

For the construction of roads in form of boulders and aggregate.As an aggregate in cement as well as lime concretes.Base material for water and sewage filters.For the manufacture of cement and lime.In the construction of masonry dams , stones of good quality and durability are of vital importance.

COMMONLY USED BUILDING STONES

Granite : Intrusive igneous rock Intrusive crystallized slowly within the earthGranite is a strong, hard & non-porous rockIt is a desirable foundation & building material.

Basalt : Extrusive igneous rockExtrusive:rapidly crystallized on the surface of earthBasalt is hard & strong but it is porous & have fractures

Limestone : Sedimentary rockIt is used as a concrete aggregateIt is used in the production of cement & lime

Marble : Metamorphosed limestoneHarder than limestoneUsed for interior work or wall or column facing

Slate : Metamorphosed clayUsed for flooring, interior or exterior wall facing.

TEST OF STONESBuilding stones are required to be tested for their different properties before they may be recommended for any specific case.1-Acid test.2- Water absorption test .3- Impact test .4- Crushing test .5- Hardness test .

ACID TEST

This is the best test to find out the action of acids on the stone. For this test about 50 to100 grams sample of stone is immersed in a solution of 1 % HCl or H2SO4 for about a week.

The sample being agitated (pressed , disturbed) at intervals. If the edges of stone are retained and there is no deposition of any loose particles on the surface, it indicates that the stone is good other wise weak and bad.

WATER ABSORPTION TESTTo ascertain the relative qualities of different stones, they are immersed in water for 24 hours and the amount of water absorbed by each specimen is noted. Greater absorption of water by the stone means that it is porous and can not resist weathering forces well . The test specimen which absorbs the smallest amount of water is the best.% Absorption =(W2 W1 / W1 ) *100

IMPACT TESTA cylinder of diameter & height 25mm is taken and placed on cast iron anvil of machine.A steel hammer of weight 20N is allowed to fall axially in vertical direction.The height of first blow is 1cm, that of second blow is 2cm and so on.The blow no (n) at which specimen breaks is noted. n represents the toughness index of stone.

CRUSHING TESTFor this test finely dressed different samples of stones are used .Their type is made flat and horizontal and covered with plaster of Paris. They are tested in a compression testing machine . The load must be applied axially and the changes in the blocks at the corresponding load are recorded. The blocks or samples which bear more loads are to be selected. Good quality stone has crushing strength more then 70 N/mm*mm.

HARDNESS TESTThis test is done to determine the hardness of stone by mohrs scale of hardness in the laboratory where as in field it can be tested by scratching with the knife.Hard stone do not so any mark of scratching.Coefficient of hardness = 20-(loss in weight in gm /3).

QUARRYING OF STONESStones are extracted from natural rocks in different sizes. The various methods which are involved in the extraction of stones from rock beds are collectively termed as Quarrying of Stones.Methods Of Quarrying :Digging or excavating, heating, wedging For soft rocks like limestone, marbleBlasting-blasting rocks with explosivesFor hard dense rocks like granite, basalt

Quarrying

DRESSING OF STONESDressing of stones is a process in which their surfaces are prepared to a form, fit to be used for any constructional purpose. Dressing is according to the type of work and demand. Purpose of Dressing: To give them good looking.To provide horizontal and vertical joints in the masonry.To make them fit, to be used for particular work.

Dressing

SEASONING OF STONESIt makes the stone hard and compact , by exposing the stone to open air for a period of six to twelve months .All the stones should be seasoned before they are used in structural work.

Characteristics and qualities of good building stone

The stone should be easily and economically obtainable in bulk .The stone should be hard, strong and durable .It should weather well.It should have fine compact texture.

It should be capable to withstand the effects of smoke and acidic atmosphere.The stone should be free from soft patches, flaws, cavities and cracks .It should be well seasoned and easily workable.

ENDThank you