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Sand

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This video will teach you about sand and its uses in masonry.

You are watching a part of a series of videos that educate novices to the field of masonry.

Music Dan-O at Danosongs.com / Incompetech.com

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In this video, you will learn how to identify good quality sand.

Fine aggregates are naturally occurring particles like sand or artificially made particles like crushed rock and stone that are used to make mortar and concrete. Sand is the most common fine aggregate available in most places. However the quality of the sand will determine the strength of its bond. Sand containing waste material, organic impurities or mineral salts are unfit to be used in construction.

Good, clean sand should be Golden Yellow in colour and filtered with a sieve so it is devoid of larger particles. Particles that are sharp and angular interlock well. Depending on the size of particles, sand is classified into different types. Generally, coarse sand is preferred for making concrete and a finer sand is preferred for brickwork and plastering.

To test the quality of sand, take a handful of it and rub it between both palms. Good quality sand with only a permissible amount of silt or clay will leave the palms clean without sticking to them.

Fill half a glass container with sand and pour clean water till the three quarters level. Shake well and allow the mixture to settle. The sand particles, being the heaviest, will immediately drop to the floor of the container.

Leave the container untouched for up to a day or until the silt and clay has settled on top of the sand. Note the level of the silt and clay ensuring that it does not exceed 4% of the sand (If you marked 10 cms of sand, the impurities settling on top of it must not exceed 4mm). If there is a high amount of impurities the sand needs to be replaced.

You have now learned to identify good quality Sand.

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