What are the Qualities of a Good Building Stone?

βœ‚ What are the Qualities of a Good Building Stone?:

β€ŽπŸš€What are the Qualities of a Good Building Stone?

The following tests are carried out for figuring out the qualities of a great building stone!

(1) Acid test

(2) Attrition test

(3) Crushing test

(4) Crystallisation test

(5) Freezing and defrosting test

(6) Hardness test

(7) Impact test

(8) Microscopic test

(9) Smith’s test

(10) Water absorption test.

Each of these tests will now be quickly explained.

πŸ’‘1. Acid Test: ✨

In this test, a sample of stone weighing about 0.50 to 1 N is taken. It is put in an option of hydrochloric acid having the strength of one per cent and it is kept there for 7 days. The option is upset at periods. An excellent building stone preserves its sharp edges and keeps its surface devoid of powder at the end of this duration.

If edges are broken and powder is formed on the surface, it suggests the existence of calcium carbonate and such a stone will have bad weathering quality. It is natural that this test cannot be used to the limestones. This test is typically performed on the sandstones.

πŸ’‘2. Attrition Test: ✨

This test is done to learn the rate of wear of stones which are utilized in roadway building. The outcomes of the test show the withstanding power of stones versus the grinding action under traffic.

Following treatment is embraced:

(i) The sample of stone is burglarized pieces of about 60 mm size.

(ii) Such pieces, weighing 50 N, are put in both the cylinders of Deval’s attrition test maker. The size and length of the cylinder are respectively 200 mm and 340 mm.

(iii) The cylinders are closed. Their axes make an angle of 30Β° with the horizontal.

(iv) The cylinders are turned about the horizontal axis for 5 hours at the rate of 30 R.P.M.

(v) After this duration, the contents are gotten from the cylinders and they are gone through a screen of 1.50 mm mesh.

(vi) The amount of product which is maintained on the screen is weighed.

(vii) The portion wear is exercised as follows –

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πŸ’‘3. Crushing Test: ✨

The compressive strength of the stone is learnt with the assistance of this test.

The sample of stone is cut into cubes of size 40 mm x 40 mm x 40 mm. The sides of the cubes are carefully dressed and ended up. The minimum variety of specimens to be evaluated is 3. Such specimens ought to be put in water for about 72 hours prior to the test and afterwards evaluated in a saturated condition.

The load-bearing surface is then covered with plaster of Paris or 5 mm thick plywood. The load is used axially on the cube in a squashing test maker. The rite of loading is 13.72 N/mm2 per minute. The squashing strength of the stone per system location is the optimum load at which its sample squashes or stops working divided by the location of the bearing face of the specimen.

πŸ’‘4. Crystallisation Test: ✨

In this test, a minimum of 4 cubes of stone with side as 40 mm are taken. They are dried for 72 hours and weighed. They are then immersed in 14 per cent option of Na2SO4 for 2 hours. They are dried at 100Β°C and weighed. The distinction in weight is kept in mind. This treatment of drying, weighing, immersing and reweighing is duplicated a minimum of 5 times. Each time, the modification in weight is kept in mind and it is revealed as a portion of initial weight.

It is to be kept in mind that the crystallisation of CaSO4 in pores of stone triggers the decay of stone due to weathering. But, as CaSO4 has low solubility in water, it is not embraced in this test.

πŸ’‘5. Freezing and Thawing Test: ✨

The specimen of stone is kept immersed in water for 24 hours. It is then put in a freezing mix at -12Β°C for 24 hours. It is then defrosted or warmed at the climatic temperature level. This must be carried out in shade to avoid any impact due to wind, sun rays, rain, etc. Such a treatment is duplicated a number of times and behaviour of stone is thoroughly observed.

πŸ’‘6. Hardness Test: ✨

To identify the solidity of stone, the test is performed as follows:

(i) A cylinder of size 25 mm and height 25 mm is gotten from the sample of stone.

(ii) It is weighed.

(iii) It is put in Dorry’s screening maker and pushed with a pressure of 12.50 N.

(iv) The annular steel disc of the maker is then turned at a speed of 28 R.P.M.

(v) During the rotation of the disc, the coarse sand of basic spec is sprayed on the top of the disc.

(vi) After 1000 transformations, the specimen is gotten and weighed.

(vii) The coefficient of solidity is learnt from the list below formula –

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πŸ’‘7. Impact Test: ✨

To identify the durability of a stone, the effect test is performed in page effect maker as follows:

(i) A cylinder of size 25 mm and height 25 mm is gotten from the sample of stone.

(ii) It is put on the cast-iron anvil of maker.

(iii) A steel hammer of weight 20 N is permitted to fall axially in a vertical instructions over the specimen.

(iv) The height of very first blow is 1 cm; that of 2nd blow is 2 cm; that of 3rd blow is 3 cm; and so on.

(v) The blow at which specimen breaks is kept in mind. If it is an nth blow, n represents the durability index of stone.

πŸ’‘8. Microscopic Test: ✨

In this test, the sample of stone goes through the tiny assessment.

The thin areas of stone are taken and put under the microscopic lense to study different residential or commercial properties such as:

(i) Average grain size;

(ii) Existence of pores, cracks, veins and shakes;

(iii) Mineral constituents;

(iv) Nature of sealing product;

(v) Presence of any damaging compound;

(vi) Texture of stone; etc.

πŸ’‘9. Smith’s Test: ✨

This test is carried out to learn the existence of soluble matter in a sample of stone. The couple of chips or pieces of stones are taken and they are put in a glass tube. This tube is then filled with clear water. After about an hour, television is intensely stirred or shaken. The existence of earthy matter will transform the clear water into filthy water.

If water stays clear, the stone will be resilient and devoid of any soluble matter. On the other hand, if the water ends up being filthy, it will show that the stone includes excessive of soluble earthy and mineral matters.

πŸ’‘10. Water Absorption Test: ✨

Following treatment is embraced for this test:

(i) From the offered sample of stone, a cube weighing about 0.50 N is prepared. Its real weight is taped. Let it be W1N.

(ii) The cube is then immersed in pure water for a duration of 24 hours.

(iii) The cube is gotten of water and surface water is rubbed out with a damp fabric.

(iv) It is weighed once again. Let its weight be W2N.

(v) The cube is suspended easily in water and its weight is taped. Let it be W3N.

(vi) The water is boiled and cube is kept in boiling water for 5 hours.

(vii) It is then gotten rid of and surface water is rubbed out with a damp fabric. Its weight is taped. Let it be W4N.

From these information, the worths of the following residential or commercial properties of stone are acquired:

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