SAND:-
Sand is small grains of silica (SiO2) formed by the decomposition of rocks. It is one of the most important construction materials. It is broadly used in concrete cement mortar, lime mortar, earth filling, etc.
Contents :-
- What is Bulking of Sand?
- Bulking of Sand Significance
- Test Procedure to determine the bulking of sand
What is Bulking of Sand?
The increase in the volume of sand due to increase in moisture content is known as bulking of sand. A film of water is created around the sand particles which forces the particles to get a side from each other and thus the volume is increased.
The increase in moisture in sand increases the volume of sand. The volume increase in dry sand is known as the bulking if sand. Bulking of sand depends on the quantity of moisture in the sand and also the size of the particles. Five to eight percent of the increase in moisture in the sand can increase the volume of sand up to 20 to 40 percent. Again, the finer the sand is more will be the increase in volume and increase in volume will be relatively less for coarser sand.
Bulking of Sand. Reference PCA Major Series 172 and PCA ST20
Bulking of sand depends on the moisture in the sand. But when the moisture is increased by adding more water, the particles of sand gets packed near each other as the film around the sand particles breaks and the bulking of sand is reduced. Dry sand and the send completely filled with water will have the exact volume. This principle is used to determine the percentage of bulking of sand in a given sample
Bulking of Sand Significance
In simplified terms, it can be said that bulking of sand is simply the looseness of soil without compacting. Usually, water reduces the pores in sand and compacts the sand.
Sand is used in concrete for reduction of segregation and fill out the pores between cement and coarse aggregates. For example, we need 1 m3 of sand in concrete, we need to know the approximate sand bulkage value. If the given sample has a bulkage of 25% then we need to take 25% more sand or 1.25 times of the sand while volume batching to get 1 m3 of sand for concrete.
If we don’t take this extra amount of sand considering the bulkage value, the total volume will be lessened to 75% after adding water. We know that the quality of concrete depends a lot on the proper proportioning of the contents. Generally, we consider the wet volume of concrete is 1.5 times the volume of dry concrete, in this case, we are typically using approximately 30% of sand bulkage and 20% of wastage. If we do not consider the bulkage of sand, the total quantity will be lessened and will impact on the overall concrete quality.
Test Procedure to Determine the Bulking of Sand
Following steps can be followed to calculate the percentage of bulking of sand in a given sample-
- Fill the measuring cylinder with the sample up to 200 ml mark.
- For accurate measurement steel scale can be used, but no compaction of sand is allowed.
- The sand is to be transferred to a container.
- The measuring cylinder is refilled with 100ml water.
- The measuring cylinder should be refilled with sample sand and stirred with a steel rod.
- Give some time so that the sand can settle.
- The level of sand will be below the 200ml mark this time. Let the present level be “a.”
- So the bulking of sand for this sample will be determined by the following equation-
BulkingofSand=200−aa×100BulkingofSand=200−aa×100
- The procedure should be repeated twice and the average value of the tree observation will be the percentage of bulking of sand for the given sample.
Uses of Sand
In the real world, there are a lot of situations where we can find uses of sand. Followings are the common sand uses.
- We can use sand to filter water; it works like an abrasive.
- We can use sand to give a grip to our painting or wall art by combining 2 cups of paint with a ¾ cup of sand.
- People make sandpaper by gluing sand to a paper.
- While bunging metal, we can mix sand with clay binder for frameworks used in the foundries.
- Sand can be used for cleaning up oil leak or any spill by dredging sand on that spill. The material will form clumps by soaking up, and we can quickly clean the mess.
- Sand can be used as a road base which is a protective layer underneath all roads
- Industrial sand is used to make glass, as foundry sand and as abrasive sand.
- One creative usage of sand is serving as a candle holder. We can try putting some sand before pouring tea light or any candle in a glass. It holds the candle still and refrain the candle from rolling by giving it an excellent decoration.
- Adds texture and aesthetic appeal to space.
- Sand is mostly pure to handle, promptly available and economically wise.
- We can make children’s sandpit to keep the play areas safer. It is quite inexpensive as well.
- We use sand in aquariums, fabricating artificial fringing reefs, and in human-made beaches
- Sandy soils are ideal for growing crops, fruits and vegetables like watermelon, peaches, peanuts, etc.
- Sand can light a path by filling mason jars with sand and tea light which is another inexpensive way to make a walkway glow.
- We can keep a small scuttle of sand near a charcoal grill for inundating flare-ups.
- Sand can be used for cleaning narrow neck receptacle by putting a little sand and warm soapy water in the container.
- We can keep an item steady which needs repairing by using sand. Burying the broken pieces under sand grains helps to hold the elements together while gluing.
- Sand helps to improve resistance (and thus traffic safety) in icy or snowy conditions.
- We need sand in the beaches where tides, storms or any form of preconceived changes to the shoreline crumble the first sand.
- Sand containing silica is used for making glass in the automobile and food industry- even household products for the kitchen.
- Sand is a strong strand which is used for plaster,mortar , concrete, and asphalt.
- The usual bricks formulated of clay only is way weaker and lesser in weight than blocks made of clay mixed with sand.
- REFERENCE TAKEN FROM WWW.CIVILTODAY.COM
