It is impossible to provide modern life without concrete. And one of constituent parts of this artificial construction material is sand. It would seem, to buy it as easy as shelling pears: it is necessary to make only the order and to make payment. However it is necessary to know how it is correct to choose sand.
What construction sand is
If you have decided to build the stone house, to concrete site on the seasonal dacha, to lay concrete paths, build strong fence, not to do you without sand. Depending on where sand was extracted, it is subdivided into river (sea), ravine and career.
Bank (sea) sand is extracted from bottom of small sites of reservoirs by means of special devices. Bank sand after drying can be used without additional cleaning as in it there are practically no impurity of clay and other pollution. Such sand very qualitative. Beach sand demands additional washing for removal of salts.
The most widespread type of sand – ravine. It and the cheapest. Such sand by means of the bucket excavator is extracted. Contains in it many impurity representing firm particles of the most various form. Thanks to what, such sand is ideal for preparation of especially tenacious concrete solution used at laying and plaster.
But it can be applied with success and in all other types of concrete work.
The pit sand contains many impurity therefore it is considered the most low-quality. Also you can find quartz, molding sand in sale.
How to choose sand for construction
Deciding from what organization you will buy sand, try to choose the reliable, checked supplier. Get acquainted with reviews of its work. Quality and dry sand has density about 1300 kilograms on cubic meter. If its density is significantly higher, it means that sand or too damp, or in it is a lot of impurity (clay, stones), and it will have an adverse effect on quality of ready concrete.
Clay content in sand should not exceed 5% (on weight). Gravel content – no more than 0.5%, at the same time maximum sizes of its particles – up to 10 mm.
Before buying sand, learn the average market prices. If it turns out that its price too low, most likely, it unimportant quality. You can make fast and evident experiment: pour out sand handful in bank with clear water and stir. If water strongly dims, so in sand there were many impurity. Certainly, the reliable supplier valuing the reputation will have all necessary documents characterizing goods. Besides, such suppliers have transport for sand delivery to clients and can answer all questions concerning it quality and use at concrete making.