Correctly to choose cement, it is necessary to learn to read its marking. In addition, it is necessary to know about what of types of this binding is optimum for preparation of water mortars and what is required for construction of the base or plates of overlappings.
Instruction
1. Most often on sale it is possible to meet portland cement of brands from M200 to M600. This binding is the most demanded in construction jobs. But it is necessary to know that this type of cement not always meets those requirements which are imposed to water mortars and products from concrete. Therefore in certain cases it is necessary to pay attention to types of portland cement: moderately termichny, resistant to sulfates, having ability quickly to harden, resistant to moisture influence, plasticized and multi-colored.
2. The cement having the increased resistance to influence of sulfates is often used during construction of large objects from reinforced concrete of hydrotechnical purpose and those which annually are exposed to seasonal processes of freezing defrosting, being in salt or fresh water. Cement with the accelerated hardening is used when it is required to accelerate process of production of construction stones or designs. Its durability significantly increases after several days after filling in form or timbering.
3. The cement resistant to moisture influence is the optimum choice in case long storage or transportation on long distance in conditions under which the increased air humidity and frequent change of its temperature is possible is required. The concrete paint is used for dressing of facades of buildings, production of road surfacings.
4. The main characteristic of cement – its durability. When choosing this construction material it is necessary to pay attention to marking which is specified on packing. The brand is higher, the cement has the bigger durability and speed of skhvatyvaniye. So, binding considerably concedes M200 brands on the strength characteristics to M500 or M600 brand. On packing the producer always specifies the weight and composition of material. Therefore it is better to buy sacked cement, but not weighing. As in the latter case there is risk to get binding poor quality.
5. If cement is necessary for construction of elements of construction which are obliged to maintain heavy weight loads (the base, floor slabs), it is recommended to use M400 D20 brand. If these objects are in conditions of the increased humidity, the best choice – M400 D0. Availability in marking of letter "D" reports that as a part of binding there are additives. Letter "B" means that this construction material has property quickly to harden. The cement possessing hydrofobization or plasticization is designated as GF and Square. Made on the basis of clinker has letter "H" in marking.
6. During the choice it is important "to read" material marking correctly. For example, buying GOST 10178-85 portland cement 400-D290-B-PL it is necessary to understand that this binding M400 brands, not less than 20% of additives contain, has property to harden quickly and incorporates softener. For finishing work use M200 and M300 cement. For production of paving slabs or other road surfacing the recommended brands – from M400 above.